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1

Readman, Russell J. "The physiological basis and consequences for nitrate leaching of novel fertiliser strategies involving foliar fertilisation of wheat." Thesis, Open University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321312.

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2

Silvertooth, J. C., E. R. Norton, and S. E. Ozuna. "Foliar Fertilizer Evaluation on Upland Cotton, 1997." College of Agriculture, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/210383.

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A single field experiment was conducted in 1997 at the University of Arizona Yuma Valley Agricultural Center. The purpose of the experiment was to evaluate foliar applications of Macro Sorb (L form amino acids) and KeyPlex (chelated micronutrients and alpha keto amino acids) foliar fertilization materials on Upland cotton. Treatments consisted of various rates and times of application of the foliar materials based upon manufacturer recommendations. Results from this single experiment revealed no differences among treatments with respect to in-season plant measurements, tissue N concentrations, or lint yield.
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3

Cook, John William. "The effect of foliar applied fertilisers on leaf diseases of cereals." Thesis, Open University, 1998. http://oro.open.ac.uk/57740/.

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The effects of foliar applied urea and potassium chloride on the severity of leaf diseases of cereals were investigated in the laboratory, glasshouse and field between 1992 and 1995. Field studies with urea gave inconsistent results with respect to severity of Erysiphe graminis and consistently increased the leaf area affected by Septaria tritici. However, potassium chloride applied as a foliar spray consistently decreased the leaf area of wheat affected by E. graminis and S. trifid compared with equivalent applications of soil applied fertiliser. Disease control was achieved at early stem extension and after flag leaf emergence but yield responses were not detected. Laboratory investigations were undertaken to determine the mechanism by which foliar applied potassium chloride reduced the leaf area affected by E. graminis. The timing of application, within seven days pre or post inoculation, had no consistent effect on the efficacy of the fertiliser. Investigations using polyethylene glycol as a control showed that the percentage leaf area affected declined linearly as the osmotic potential of the solutions were increased. Light microscopy revealed that the germination of spores in solution and on treated leaves was reduced as the osmotic potential of the solutions were increased. Spores which did germinate developed normally but those on leaves treated with solutions of high osmotic potential rarely formed haustoria. This suggested a second mechanism acting inside the leaf. Multiple regression analysis of experimental data indicated that the inhibition of spore germination was the major response reducing the area of the leaf affected. Although the data were not conclusive it appeared that the increase in leaf water potential, following the foliar application of potassium chloride, was involved in the control of E. graminis.
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4

Silvertooth, J. C., S. H. Husman, J. E. Malcuit, and T. A. Doerge. "Upland Cotton Resposne to Soil and Foliar Applies Potassium Fertilizer, 1991." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/208656.

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A single field experiment was conducted near Gila Bend, Arizona in 1991 to evaluate the effects of both soil and foliar applied potassium (K) fertilizersto Upland (Gossvpium hirsutum L.) cotton to a soil testing 315 ppm K (high). Soil applied K fertilizer at rates of 0, 75,150, and 225 lbs. K₂O/acre as K₂SO₄ were broadcast and preplant incorporated before listing. Foliar applications were made in all combinations with the various soil applied K treatments and consisted of four applications of 4.6 lbs. K₂O /acre as KNO₃ (10 lbs. KNO₃ /acre) over the first fruiting cycle, by a ground applicator with approximately 25 gallons per acre as carrier. No differences among treatments were detected by any plant growth measurement taken, plant tissue analyses, lint yield or lint quality determinations which were made over this experiment. Conclusions (preliminary) based upon these results indicate that K fertilization was not warranted under the conditions characterized in this single field experiment.
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5

Radley, Reed Alan. "The effect of foliar applications of sprays made from kelp (macrocystis integrifolia) on growth of phaseolus vulgaris : b possible role of algal phytohormone-like substances." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29773.

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The effects of two applications of foliar sprays made from kelp (Macrocystis intearifolia Bory) on growth of beans (Phaseolus vulgaris L.) under three moisture regimes were investigated. Date of kelp harvest had little effect on plants grown in water excess or deficit conditions, although means for kelp collected in spring tended to be higher. On soils maintained near field capacity, spray made from kelp collected in July resulted in increases in some bean yield components beyond the effects of kelp collected in spring or fall. The effect of storage of liquefied kelp at room temperature was also investigated and found to be soil moisture dependent. Leaf and root weights of plants grown in field capacity and dry soil respectively were lower for plants treated with kelp aged for 118 days compared to plants treated with kelp stored for longer or shorter durations. In wet soil conditions, the effect of sprays on plant height was reduced by storage of the liquefied kelp. Kelp extracts were fractionated by solvent partition. The butanolic fraction was shown to increase significantly many yield variables under wet soil conditions. This fraction had cytokinin-like activity in two bioassay systems, and contained substances co-eluting with isopentenyl adenine and zeatin in column, thin layer, and gas-liquid chromatography systems. Non-significant increases for some plant yield components resulting from application of unfractionated kelp paralleled these increases. A kelp fraction with undefined constituents increased some yield variables of plants grown in field capacity soil, as did a fraction with auxin and gibberellin-like activities in bioassay. The presence of inhibitors in the kelp was indicated by significantly lower pod yields under dry soil conditions, and a reduction in cytokinin-like bioassay activity when increasing amounts of kelp were assayed. The possibility that phytohormone deficits resulting from root stress are ameliorated by some components of the kelp spray is discussed.
Land and Food Systems, Faculty of
Graduate
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6

Ippersiel, Denis. "The effect of foliar nitrogen fertilization on nitrogen distribution, yield and protein quality of forage corn /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63798.

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7

Rethwisch, Michael D., Mark Reay, Jessica Grudovich, D. Michael Ramos, and Jessica Wellman. "Evaluation of AuxiGro® WP and Foliar Fertilizers on Bermudagrass Seed Production." College of Agriculture, University of Arizona (Tucson, AZ), 2005. http://hdl.handle.net/10150/203817.

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AuxiGro® WP was evaluated for effects on bermudagrass seed production in the Palo Verde Valley of far eastern California. Four rates of this product, in addition to a 4 oz./acre rate with two fertilizers were tested, as were the fertilizers only to separate treatment effects. Highest yields from subplot harvests were noted from the 2 and 4 oz./acre rates of AuxiGro® WP, and germination percentages from these treatments and resultant pure live seed were also numerically higher (81-99 lbs./acre) than that noted from untreated bermudagrass, although most plant parameters did not result in statistical difference.
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8

Augustin, Christopher Lee. "Fertilizer Management Strategies of Soybean (Glycine Max, L. Merrill) in Northcentral and Northwestern North Dakota." Diss., North Dakota State University, 2019. https://hdl.handle.net/10365/31355.

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Soybean (Glycine max L. Merrill) is a new cash crop for north central and northwestern North Dakota producers. Soils and climate in these new soybean areas differ from those regions where the current fertilizer recommendations were based. Northcentral and northwestern North Dakota is more undulating, drier, cooler, and has differencing soils than eastern North Dakota and Minnesota. A three-year study to evaluate soybean best management practices was conducted during the 2016 to 2018 growing seasons. Each year, the study consisted of two sites and 12 treatments. By design, one site was on acidic (pH < 6) soil while the other was on alkaline (pH > 7.3) soil. Both site treatments were: untreated check, inoculated with rhizobia (B. japonicum L.), broadcast urea (55 kg ha-1), broadcast MAP (monoammonium phosphate, 11-52-0) (110 kg ha-1), in-furrow 10-34-0 (28 L ha-1), in-furrow 6-24-6 (28 L ha-1), foliar 3-18-18 (28 L ha-1) at V5 and R2 growth stages, and foliar 3-18-18 (28 L ha-1) with sulfate (1.1 kg ha-1) at V5 and R2. The acidic sites alone included two treatments of sugar beet (Beta vulgaris L.) waste lime (4.4 Mg ha-1 and 8.8 Mg ha-1). The alkaline sites alone received treatments of iron ortho-ortho-EDDHA (1.8% Fe) (7.1 L ha-1), and sodium (naked- without Fe) ortho-ortho-EDDHA (7.1 L ha-1). Treatments did not impact soybean yield, protein content or oil content at the 95% significance level. Sugar beet waste lime surface applied at planting at rates of 4.4 Mg ha-1 and 8.8 Mg ha-1 increased soil pH to a depth of 10 cm over the course of the growing season.
North Dakota Soybean Council
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9

Jordan, Daniel L. "IMPACT OF HIGH-INPUT PRODUCTION PRACTICES ON SOYBEAN YIELD." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/36.

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High-input management practices are often heavily marketed to producers to increase soybean [Glycine max (L) Merr.] yield in already high-yielding environments. Field research was conducted in three locations within 6 states (Arkansas, Iowa, Kentucky, Louisiana, Michigan, and Minnesota) in 2009 to determine the effect of seed treatment, inoculant, foliar fungicide, additional soil fertility beyond state recommendations, foliar fertilizer, increased population over state recommendations, and narrow row spacing on yield. The high-input system (combination of the management practices) yielded higher than standard-input system (University recommended management practices) in only 8 of the 18 locations. Narrow rows, in both the high and standard-input systems, only increased yield in 4 locations. Inoculant did not increase yield at any location. Foliar fertilizer application and seed treatment increased yield in one location each. The additional soil fertility and fungicide application increased yield in two locations each. The increased population increased yields in 3 of the 18 locations; while an additional fungicide application at R5 only increased yield in 1 location. Foliar fertilizers at rates above commercial use did not increase soybean yield in Kentucky in 2008 or 2009. High-input production practices were largely unsuccessful at increasing soybean yield in these studies.
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10

Karim, Mohammad R., Glenn C. Wright, and Kathryn C. Taylor. "Effect of Foliar Boron Sprays on Yield and Fruit Quality of Citrus." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/220555.

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Deficiency of boron (B) in citrus has serious consequences for tree health and crop production. There is evidence that B deficiency may be a problem in Arizona citrus. Certainly, many symptoms of B deficiency are apparent, especially on the Yuma Mesa. A field trial was conducted at Yuma, Arizona to examine the effect of foliar boron application on fruit yield and quality of Citrus sinensis and C. limon. Boron was applied to 5 year old Citrus sinensis cv. Hamlin and C. limon cv. Rosenberger Lisbon trees at 5 different concentrations (0 ppm, 500 ppm, 1000 ppm, 2000 ppm, 3000 ppm) either before flowering or after flowering. At harvest, fruit yield and quality, and boron concentrations were determined. Foliar application appeared to increase leaf boron concentration (r= 0.50, p= 0.004). Fruit set was increased in Hamlin trees receiving bloom and post bloom applications of boron at the 1000 ppm level. Boron applications had no significant effect on lemon yield in these studies. This fruit set increase in Hamlin accounted for a 35% increase in overall yield relative to control trees. However, there was no significant difference in fruit weight, fruit pH, titratable acidity, peel thickness, juice volume, or soluble solid content of the fruits among treatments. Previous studies indicate that boron influenced in vivo and in vitro pollen germination in many crops. A plausible explanation for increased fruit yield may be that the applied boron was transported to the flowers where it exerted its influence of increased fruit set through an effect on pollen viability and/or pollen tube growth. However, clearly boron supplementation must be performed judiciously to avoid fruit drop from over -application of the element.
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11

Lewis, D. James. "Foliar-applied phosphate on potatoes (Solanum tuberosum L.) : factors affecting uptake by the leaves and the effects on growth and yield." Thesis, Open University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320528.

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12

Rasmussen, Heidi. "Foliar Application of Iron Chelated Fertilizer and Surfactants for Management of Iron Deficiency Chlorosis in Soybeans." Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/27708.

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Iron deficiency chlorosis (IDC) is a production challenge for farmers growing soybeans [Glycine max (L.) Merr.], especially in the Red River Valley. It is critical to correct this deficiency as soon as symptoms arise before growth, and ultimately yield, is negatively impacted. Field experiments of foliar applied iron fertilizers (o-o-EDDHA, o-o-EDDHSA, HEDTA, and an amino acid) and suitable adjuvants (HSOC [high surfactant oil concentrate], non-ionic surfactant, acidifier, and organosilicone surfactant), to control IDC were conducted during the 2013 and 2014 growing seasons, respectively. There was high variability among the results for both the SPAD meter readings and soil iron concentration. The yield values were greater in the treated plots than with control plots, but not significantly so. Further experiments should be conducted to gain more knowledge on the prolonged use and efficiency of these products in the correction of IDC.
North Dakota Soybean Council
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13

Mueller, Nathan D. "Improving corn and soybean yield through fertility and weed management practices." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/14844.

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Doctor of Philosophy
Department of Agronomy
Dorivar Ruiz Diaz
Winter annual weeds (WAW) could affect nitrogen supply for corn production. The objectives of first study were to determine the diversity and abundance of WAW and to evaluate the effect of delaying herbicide applications on nitrogen supply and no-till corn response. Research was conducted in 2010 and 2011 at 14 sites in eastern Kansas. A factorial arrangement of three herbicide application dates (Nov.-Mar., April, and May) and five N rates were used. The three most abundant WAW across sites were henbit, purslane speedwell, and horseweed. Delaying herbicide application until April significantly reduced early corn N uptake by 52 mg N plant-1, chlorophyll meter readings at silking by 3.4%, and grain yield by 0.48 Mg ha-1 across sites. An additional 16 to 17 kg N ha-1 was needed to maintain yield if herbicide application was delayed until April. Starter and foliar micronutrient fertilization can potentially increase corn and soybean yield. The objectives of the second study were to evaluate crop response from combinations of starter and foliar fertilizers that contain N-P-K mixtures with and without a blend of micronutrients at four sites for each crop under irrigated conditions. No early corn growth or yield increase was attributed to application of micronutrients (Fe, Mn, Zn, Cu, and B) beyond what was achieved with N-P-K starter fertilization. There was an increase in soybean height (8 cm) and yield (293 kg ha-1) with starter fertilizer containing N-P-K plus micronutrients over the control. No increase in corn or soybean yield was obtained with foliar fertilization. The objective of the third study was to compare soil mobility and changes in soybean nutrient concentration in the leaf and seed from Mn and Zn sources (EDTA and oxysulfate) at two sites. Zinc sources were more mobile in the soil. Both Zn sources increased seed Zn concentration. Manganese oxysulfate increased seed Mn concentration. However, soybean trifoliolate leaf and seed Mn concentration decreased with soil-applied Na2EDTA and MnEDTA. This response was attributed to formation of FeEDTA and increased Fe supply that reduced root Mn absorption. Manganese EDTA is not recommended for soil application.
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14

Craft, John Clayton. "Evaluating the Response of Modern Soybean Cultivars to Commercial Foliar and Soil-Applied Nitrogen Fertilizers." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523869530347799.

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15

Rethwisch, Michael D., D. Michael Ramos, Manuel Luna, and Jessica Wellman. "Effects of Calcium Containing Foliar Fertilizers on DPL449BR Cotton in the Palo Verde Valley, 2005." College of Agriculture, University of Arizona (Tucson, AZ), 2007. http://hdl.handle.net/10150/198217.

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Seven foliar fertilizers containing calcium were applied to DPL449BR cotton in the Palo Verde Valley on June 24, 2005, immediately after three consecutive days of level one stress. Plants had been blooming prior to application and had several open blooms per plant at time of application. All treatments increased level of leaf chlorophyll by at least 7.4% when compared with the untreated check as with a Minolta 502 SPAD meter on July 7, with greatest (21.3%) increase noted from Calcium Metalosate®. No statistical differences were noted for this parameter on July 13, and by July 21 highest mean leaf chlorophyll content was noted from untreated cotton. Leaf chlorophyll was lowest in untreated cotton on July 25 however. Shortest stigma lengths beyond anthers on July 13 was noted in treatments with highest amounts of calcium applied per acre, while all treatments had numerically fewer abnormal flowers than the untreated check on July 21. Treatments resulted in slightly taller plants than the untreated check on July 6 and 21, and more nodes on July 6. Most treatments also resulted in more fruiting nodes per plant on July 21 and August 4. Greatest height:node ratios were noted in CalMax® treated cotton on all three sample dates. Highest retention percentages were noted in untreated cotton on July 6 and August 4. All treatments resulted in numerically more fruiting structures/plant than the untreated check on July 21, although only CalMax® treated cotton had significantly more. Most treated cotton had fewer such structures per plant on August 4 than on July 21, however such structures in untreated cotton increased during this time. Calcium Metalosate® was the only treatment that resulted in more seed cotton/acre than the untreated check. Calculated lint yields varied, and reflected the single datum turnout percentage for each treatment derived from commercial ginning of modules. Wide variation in turnout data do not appear to be supported with differences in cotton quality data, as similar economics were noted for all cotton lint on a per pound basis.
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16

Rethwisch, Michael D., Rogellio Perez, Steven Morrison, Larry Parker, and Julio Juan. "Effects of Foliar Applied Fertilizers on Yield and Quality of Late Spring Cantaloupes and Honeydews." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2005. http://hdl.handle.net/10150/215012.

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A number of foliar fertilizers were evaluated for their effects on yield and quality of both cantaloupes and honeydews. None of the treatments or treatment combinations resulted in statistical increases or decreases for numbers of cantaloupes or honeydews when compared with the untreated check. A highly significant increase of one treatment regimen (which contained calcium) was noted for cantaloupe weights when compared with the untreated check. Statistical differences were not noted for honeydew weights for this treatment although it also resulted in highest calculated weights of honeydew/area of treatments evaluated. All treatments resulted in numerically higher brix for cantaloupes than the untreated check, thought to be a response to pounds of melons/unit area as the untreated check had the least cantaloupe weight. No differences were noted for cantaloupe seed cavity diameters.
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17

Wilcox, M., and C. A. Sanchez. "Evaluation of Foliar Applied Nutritional Mixes on Crisphead Lettuce for Yield, Quality and Incidence of Tipburn." College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/214714.

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18

Rethwisch, Michael D., and Mark Reay. "Effects of foliar fertilizers and carbohydrates on alfalfa yields and quality during the summer slump period." College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/205396.

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Six treatments containing carbohydrates and/or fertilizer were applied to alfalfa shortly after cutting in July 2002 to help ascertain if foliar applied carbohydrates would be helpful in overcoming summer slump of alfalfa hay production in the desert southwest. No significant differences were noted for any treatment for yield or quality when compared with the untreated check, although a trend for increased quality from treatments was noted. Highest yielding treatment was DC34, which increased tonnage by less than 0.1 tons/acre compared with the untreated check. DC34 was also among the highest in alfalfa quality. Alfalfa treated with Amaze® had the highest quality, but no affect on yield. As applications were made when little green foliage was available, most of the applied treatments did not actually contact green tissue but brown/dessicated alfalfa tissue or bare soil. Applying treatments during the regrowth cycle when more foliage is available may result in improved results as suggested by the trends noted from this experiment's treatments, however further testing will be necessary to verify such results.
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19

Mudau, N. Fhatuwani (Nixwell Fhatuwani). "Yield and fruit quality of citrus species relative to foliar sprays of macronutrients." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52616.

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Thesis (MScAgric)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: Yield and fruit quality of Citrus species relative to foliar sprays of macronutrients Marginal fruit colour and poor internal quality have been primary problems in the production of early-maturing mandarins in the Western Cape region (34 Os t 9°E). This leads to a reduction in the percentage of exportable fruit, a delay in the picking and consequent reduction in internal quality due to over-maturity. Therefore, a well-developed rind colour and internal quality of citrus are quality parameters of major importance in the fruit market. The effect of soil-applied limestone ammonium nitrate (LAN) and foliar low-biuret on fruit colour, yield and internal fruit quality of 'Mihowase' Satsuma on 'Troyer' citrange rootstock were evaluated. A significant reduction in leaf N levels was recorded where soil N has been reduced from 168 kg N/ha per annum to 126 kg Nlha per annum. Nitrogen applications influenced internal quality, although differences between treatments were too small to be of commercial importance. Despite tree appearance being more yellow in some years where N was predominantly applied as foliar spray, no consistent reduction in fruit size or yield was found. There were no clear significant differences in fruit colour, probably due to the fact that leaf N-Ievels were still within or below the norms suggested for Satsuma. The effect of Seniphosf , a mineral mixture of 31Og/L P20S, 56g/L CaO and 30g/L total N, and mono-potassium phosphate (MKP) [52% P20Sand 34% K20] on fruit colour, yield and internal fruit quality of mandarins, viz., 'Mihowase' Satsuma and 'Nules' Clementine on 'Troyer' citrange rootstock were evaluated. Seniphos'" and MKP applied during autumn colour break also did not influence fruit colour, yield and internal fruit quality, viz., juice content (%), total soluble solids (TSS), titratable acid (TA) and TSS:TA ratio of 'Nules' Clementine and 'Mihowase' Satsuma. In the Citrusdal region of South Africa (Western Cape Province), rind roughness is a general problem which often limits the percentage of exportable fruits. The effect of foliar mono-potassium phosphate (MKP) applied at 3% or 5% and urea ammonium phosphate (UAP) at 2% at 4 or 6 weeks, respectively, after full bloom (AFB) on yield, internal and external fruit quality (rind texture) of Citrus spp on rough lemon rootstock were evaluated. MKP and UAP had no consistent effect on yield, juice content (%), TSS, TA and TSS:TA ratio of 'Nouvelle' tangor, 'Valencia' orange, 'Shamouti' midseason and 'Oroval' Clementine. MKP and UAP sprays significantly, but inconsistently improved rind texture of 'Nouvelle' tangor, 'Shamouti' midseason and 'Valencia' orange. However, no positive effect was found on rind texture of 'Oroval' Clementine and 'Eureka' lemon. Inconsistent effects ofMKP and UAP sprays were also found on % leafN, P and K.
AFRIKAANSE OPSOMMING: Opbrengs en vrugkwaliteit van sitrus spesies relatief tat blaar toedienings van makroelemente Marginale vrugkleur en swak interne kwaliteit is die prim ere produksieprobleme in vroee seisoen mandaryne in die Wes-Kaap (34 Os 19°E). Die gevolg is 'n lae persentasie uitvoerbare vrugte omdat die oesdatum uitgestel word wat 'n afname in interne kwaliteit veroorsaak weens oorrypheid. Goed ontwikkelde skilkleur en interne kwaliteit is dus van groot belang vir bemarking van die vrugte. Grond-toegediende kalksteen-ammonium-nitraat (KAN) en lae biuret ureum se effek op vrugkleur, oesgrootte en interne vrugkwaliteit van 'Mihowase' Satsuma op 'Troyer citrange' onderstamme is ge-evalueer. 'n Betekenisvolle afname van die N viakke in die blare is gevind nadat grondtoediening van N vanaf 168 kg N/ha/jaar na 126 kg N/ha/jaar venninder is. N toedienings het interne kwaliteit beinvloed, maar die verskille tussen die behandelings was nie van kornmersiele waarde nie. Al was die boomvoorkoms geler in sommige jare waarin N hoofsaaklik as blaarvoedings toegedien is, was daar nie konstante afnames in vrug-of oesgrootte nie. Daar was geen betekenisvolle verskille in vrugkieur nie, waarskynlik omdat die blaarvlakke van N steeds binne die nonne daarvoor in Satsumas was. Die effek van Seniphos ('n minerale mengsel van 310g/L P20S, 56g/L CaO en 30g/L totaal N en monokaliumfosfaat (MKP) [52% P20S en 34% K20] op vrugkleur, oesgrootte en interne vrugkwaliteit van 'Mihowase' Satsumas en 'Nules' Clementine op Troyer citrange onderstarnme is geevalueer. Seniphos en MKP, toegedien tydens kleurbreek in die herfs, het ook nie skilkleur of interne vrugkwaliteit (sappersentasie, totale oplosbare vaste stowwe (TOV), suurheid (TS) en TOV:TS) betekenisvol bemvloed nie. In die Citrusdal-omgewing in die Wes-Kaap Provinsie (Suid-Afrika) is skilgrofheid 'n algemene probleem wat die hoeveelheid uitvoerbare vrugte beperk. Die effek van blaartoegediende MKP teen 3 en 5% en ureum-amrnoniurn-fosfaat (UAP) teen 2%, op onderskeidelik 4 of 6 weke na volblom, is geevalueer ten opsigte van oesgrootte, interne en ekstenne (skil grofheid) vrug kwaliteit in Citrus spp op growweskilsuurlemoen onderstam. Nie MKP of UAP het konsekwente verskille getoon t.o.v. oesgrootte, sappersentasie, TOV, TS, of TOV:TS in 'Nouvelle' tangor, 'Valencia' orange, 'Shamouti' midseison of 'Oroval' Clementine nie. Skiltekstuur is egter betekenisvol, hoewel inkonsekwent, verbeter in laasgenoemde drie. Skiltekstuur van 'Oroval' Clementine en 'Eureka' suurlemoen is nie bemvloed nie. Blaarpersentasies van N, P en K is ook inkonsekwent deur MKP en UAP beinvloed.
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20

Rethwisch, M. D., E. Duran, J. Seiler, J. Nelson, and P. Hayden. "Effects of Foliar Fertilizers Containing Calcium on Early June Planted Cotton in the Palo Verde Valley, 2000." College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/197912.

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Three foliar fertilizers containing calcium were applied at first bloom to evaluate effects on late planted (June 1) cotton in the Palo Verde Valley. Application of Calcium Metalosate resulted in increased retention percentages when compared with other foliar fertilizers at 21 days post treatment as well as more nodes/plant and calculated fruiting structures/plant. Yields did not reflect these differences however, as highest overall yields were from the untreated check, which yielded about 100 lbs. of lint/acre more than foliar fertilizer treatments. Foliar treatments did result in numerically lower micronaire and longer fibers from first pick cotton. Cotton from the first pick Calcium Metalosate treatment was strongest, but similar to other treatments. Foliar treatments did result in increased cotton value/acre by $65-95/acre, but differences noted were not consistent across field. Increased value noted for fertilizers was associated with areas of field with lowest retention rates in the untreated check at three weeks post application, and further reduction in lint quality value of untreated cotton, due perhaps to crop stresses.
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21

Camargo, Edinalvo Rabaioli. "Influência da aplicação de fertilizantes e fungicida sobre o enchimento de grãos e o desempenho agronômico do arroz irrigado." Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/5123.

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Increasing green leaf duration during grain filling in rice, using management practices to enhance plant nutrition and health, can increase grain yield. To test this hypothesis, two experiments were conducted in 2005/06. The first experiment with the objectives of evaluating the effects of nitrogen (N) and fungicide application at booting stage on 1) the green leaf area duration and grain yield and 2) on the evolution of the dry mass accumulation in grains. The treatments were three N rates (50, 100 and 150 kg ha-1) and management practices during the booting stage (supplementary application of 30 kg ha-1 N, fungicide application, and the combination of the previous treatments, including a check treatment). The treatments were arranged in a randomized block design, in a factorial scheme with four replications. Interaction among the treatments was not verified during rice grain filling. Leaf area and senescence, yield, yield components, and evolution and rate of dry mass accumulation in panicle were not affected by the management practices applied on the booting stage. The second experiment had the objective of evaluate the effect of fertilizers applied to seeds or at the booting stage on green leaf maintenance and rice performance. The treatments, which were arranged in a randomized block design with four replications, used ten foliar fertilizers available in the market, two seed treatment products, one fungicide, and a check treatment. The treatments did not affect the variables studied. The average yield was about 10,000 kg ha-1, showing that there was no limitation on plant growth and yield. The products used in this study did not increase the duration of leaf area, the yield and, the grain quality of irrigated rice.
A possibilidade de ampliar a duração da capacidade fotossintética durante o período de enchimento de grãos do arroz irrigado com utilização de práticas de manejo que interfiram na nutrição e sanidade das plantas, pode aumentar a produtividade de grãos. Com este propósito foram conduzidos dois experimentos no ano agrícola de 2005/06. O primeiro experimento, com a aplicação de nitrogênio (N) e fungicida no estádio de emborrachamento, teve como objetivos: 1) avaliar a duração da área foliar fotossintetizante e a produtividade de grãos e 2) avaliar a evolução e a taxa de acúmulo de massa seca dos grãos da panícula. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições. Os tratamentos, arranjados em esquema fatorial, constituíram-se de três doses de N (50, 100 e 150 kg ha-1) e práticas de manejo conduzidas durante o estádio de emborrachamento (aplicação suplementar de 30 kg ha-1 de N, pulverização com fungicida, combinação das práticas anteriores e tratamento testemunha). Não foi verificada interação entre os fatores estudados para as avaliações procedidas durante o período de enchimento de grãos. As práticas de manejo realizadas no emborrachamento não alteraram a área foliar, a progressão da senescência foliar, a produtividade de grãos, os componentes da produtividade, a evolução e a taxa de acúmulo de massa seca dos grãos na panícula. O segundo experimento teve como objetivo avaliar a utilização de diferentes fertilizantes, aplicados via sementes ou no estádio de emborrachamento, sobre a manutenção da área foliar e o desempenho agronômico do arroz irrigado. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições. Os tratamentos foram compostos por 10 fertilizantes foliares disponíveis no mercado, dois produtos aplicados via sementes, um fungicida e a testemunha. Não foi verificado efeito dos tratamentos aplicados para nenhum dos parâmetros avaliados. A produtividade de grãos situou-se em 10.000 kg ha-1, indicando que não houve limitação para os níveis produtivos obtidos. Os produtos utilizados no presente estudo não aumentaram a duração da área foliar, a produtividade e a qualidade física dos grãos no arroz irrigado.
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22

Williams, Emmy R. "The Benefit of Foliar Applied Copper Fertilizer on Romaine Lettuce grown in low Copper Soils of The Coastal Santa Maria, California." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/68.

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The importance of trace elements nutrients to vegetable crops has received more attention in recent years. Accordingly this experiment investigated the benefit of foliar applied copper fertilizer on romaine lettuce (Lactuca Sativa Longifolia) grown in low soil Copper (Cu) concentration in the coastal Santa Maria, California. The various rates of Cu fertilizer applied include untreated (control), 100, 200, 400 and 800 grams per acre of CuSO4.5H 2O, using a one time and a split application methods. Three consecutive individual experimental fields were established starting in late spring through the fall of 2008. The soil texture was a loam in all three of the experimental fields. Positive responses in weight increase were found due to these treatments, however was not statistically significant. The maximum responds in weight increase was identified with the one-time application of 200 and 400 grams/acre of CuSO4 but weight decline was observed at the higher rates of 800 grams/acre. The optimum weight increases were between 4.4 and 6 percent higher than the untreated plots. The treatments significantly increased the uptake of Cu by plants (pvalue <0.001). When analyzed collectively, significant difference was found in plant weights between the three experimental fields. Crops harvested one week earlier than scheduled produced 21% lower mean weight than those harvested on time. No apparent physical damage was identified in plants having leaf cu concentrations exceeding the suggested toxic level of 150 ppm but weight decline was observed thereafter. In 2009 an additional experimental field was established in a sandy loam, 8% clay and was completed in March. Rate of applications was modified to include untreated control, 200, 400 and 500 grams/acre, at one time application only. Again Positive responses in weight increase were found due to these treatments, however was not statistically significant. The optimum result in weight increase was found with the application of 200 grams/acre of CuSO4. The overall mean weights of the plants were comparatively higher than that of the three previous experimental fields. The weight increase was 7.5% higher than the untreated plots. Key Words: Foliar; CuSO4.5H 2O (Cu Sulfate Pentahydrate); Trace elements nutrients.
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23

Keane, Michael Gerard. "Aspects of needle morphology, biomass allocation and foliar nutrient composition in a young fertilized stand of repressed lodgepole pine." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25811.

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The dramatic decline in stand productivity associated with very high stand densities in naturally regenerated post-fire interior lodgepole pine (Pinus contorta var. latifolia) stands is called "repression". The reasons for it are unknown. Biomass allocation, needle morphology and foliar nutrition associated with repression were studied in a 20-year-old stand on plots at five densities ranging from 3,500 to 109,000 sph and fertilized at 0, 100 and 200 kg N ha⁻¹ with ammonium nitrate. At higher stand densities, specific leaf area increased while leaf area index declined and light intensities increased below the canopy. As stand density increased from 5000 sph to 90,000 sph, the above-ground biomass decreased from 61 t ha⁻¹ to 16 t ha⁻¹, the proportion allocated to the stem increased from 58% to 78% and the leaf area/sapwood area decreased from 0.3 to 0.13 m² cm⁻². Mean earlywood percentage decreased from 62% to 8% in codominants at 6,500 and 109,000 sph respectively. Although nitrogen deficiency was evident in all stand densities, there were no significant differences between vigorous and repressed stands for the various macro- (N, P, K, S) or micro-nutrients (Cu, Fe, 'active' Fe) examined. It is hypothesized that the decreased proportion of earlywood in repressed trees causes a reduction in stem conductivity leading to the reported drop in the leaf area/sapwood area ratio. The resulting decrease in the photosynthetic/respiratory surface area ratio in repressed stands may lead to their reduced productivity.
Forestry, Faculty of
Graduate
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24

Medina, Carolina. "Nutrient release patterns of coated fertilizers used for citrus production and their effect on fruit yield and foliar nutrition." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0014281.

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25

Spankie, Heather A. (Heather Anne). "Fertilization effects on soil and foliar nutrient status in relation to declining sugar maple (Acer saccharum Marsh.)." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59435.

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Eight fertilization treatments were applied in May 1987 to two sugar maple stands. This was followed by soil and foliar sampling and decline evaluation in mid-summer 1987 and foliar sampling and decline evaluation in mid-summer 1988.
Trees selected for sampling purposes on average showed evidence of light to moderate decline. Foliar nutrient status was found to be poor at both sites, with Ca, Mg, K and P at or very near to deficiency levels although foliar molar ratios for Ca/K, Ca/Mg and Ca/Al were well within their respective critical ranges.
Fertilization had significant effects on several elemental concentrations of the soil and foliage at the Entrelacs sites. Effects in general showed an increase in base cation concentrations when those elements were supplied in high enough quantities in the fertilizers. Fertilization had no significant effect on decline levels.
Positive correlations were obtained between soil B horizon levels and foliar Ca, Mg and K and between soil FH horizon levels and foliar K and Al.
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26

Grove, Ivan Geoffrey. "The effects of fertilisers, particularly foliar applied, on the potato plant's tolerance of attack by the potato cystnematodes, Globodera rostochiensis and G. pallida." Thesis, Open University, 1999. http://oro.open.ac.uk/54927/.

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Potato cyst nematodes, PCN, cause major yield loss in commercial potato production. One of the mechanisms of yield loss cited is a reduction in the uptake of the major nutrients nitrogen (N), phosphorus (P) and potassium (K). For the work described in this thesis, it was hypothesised that nutrient application via the foliar route could by-pass the PCN-damaged plant root system, ameliorate the PCN-induced nutrient deficits and increase plant yield and tolerance of PCN attack. None of the three nutrients investigated (N, P, K) was individually shown to limit plant growth or yield of PCN-infected plants. However, plant nutrient concentrations were affected by PCN-infection: N and K concentrations were reduced by 30 days after planting (DAP); N and P concentrations were significantly reduced by 56 to 61 DAP; but N and P were significantly greater in plants by 104 DAP. PCN-infection also significantly retarded plant emergence, and reduced plant growth and yield in all investigations. Applying placed liquid fertiliser increased the plant nutrient concentrations but did not increase tuber yield significantly. Applying one third of the recommended fertiliser quantity as foliar applied nutrients effectively replaced seedbed application, increased the nutrient concentrations within the plants and gave equivalent or higher tuber yields than in plants receiving all of the fertiliser in the seedbed. Applying all of the recommended quantity of N in the seedbed at planting did not increase early plant growth, although it did redress some of the PeN-induced nutrient deficits, and appeared to aggravate the yield loss associated with PCN infection. Applying foliar N on five occasions, at approximately 14-day intervals, produced small but consistent yield improvements by increasing ground cover and leaf area index. Yield improvements were also seen where applications included either foliar K within the foliar N application, or when one early foliar P application was made with the first of four or five foliar N applications. Applying foliar P alone on four occasions at approximately 5-day intervals from early post-emergence, or five occasions at approximately 14 day intervals from tuber initiation, reduced plant growth and yield. However, even where nutrient concentrations within PCN-infected plants were increased to the same level as, or greater level, found in relatively PCN-free plants, no significant plant growth benefits occurred. Therefore, it is postulated that a separate mechanism, i.e. phytohormone imbalance, may be solely or additionally responsible for the poor growth of PCN-infected plants. Field and glasshouse investigations showed contrasting effects of nutrients, especially foliar-applied, and nematicide applications, and highlighted the greater suitability of field experimentation for these types of investigation. The Diagnosis and Recommendation Integrated System (DRIS) was investigated as an alternative diagnostic tool to aid the identification of nutrient disorders. Although no remedial nutrient applications were made as a result of the findings from this method, it suggested that P was most limiting for early plant growth and, in contrast to the statistical analysis which showed no limitations, K was most limiting for plant growth later in the season. In conclusion, it is suggested that foliar nutrient applications can benefit the growth, yield and tolerance of PCN-infected plants, but that plant tolerance may benefit further if nutrient applications match the requirements of the plant as shown by plant nutrient analyses.
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27

Lambais, George Rodrigues. "Aminoácidos como coadjuvantes da adubação foliar e do uso do glifosato na cultura de soja." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-28062011-145152/.

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Este trabalho teve como objetivo avaliar a influência dos fertilizantes foliares a base de aminoácidos livres na utilização conjunta de práticas agrícolas como a aplicação de glifosato e a adubação no solo com P e K em soja BRS 255 RR. As avaliações foram realizadas nos parâmetros biométricos, nutricionais, metabólicos e produtivos através das variáveis: altura, valor SPAD (clorofilas), área foliar, biomassa aérea (massa fresca e seca de folhas e caules), macronutrientes e micronutrientes nas folhas, atividade da nitrato redutase (NR), glutamina sintetase (GS), concentração de proteínas totais solúveis (PTS), número de vagens, massa fresca e seca de vagens, massa média de 100 grãos, massa total de grãos, teores de lipídeos e proteínas acumulados nos grãos. Foram conduzidos dois experimentos em paralelo, com os produtos Ajifol e Flororgan, em ambiente natural utilizando vasos de polietileno com capacidade para 20 litros. O delineamento utilizado foi em blocos casualizados, onde cada unidade experimental foi constituída de três plantas de soja por vaso preenchido com 20 kg de substrato (Latossolo vermelho distrófico argiloso). A adubação no solo com P e K (1,00 e 0,24 g kg-1, respectivamente) foi realizada 30 dias antes da semeadura. As aplicações do Ajifol (1,0 L ha-1), Flororgan (2,5 L ha-1) e glifosato (0,3 L ha-1) foram realizadas via pulverização foliar no estádio fenológico V5, referente aos 35 dias após a germinação. As amostragens de altura e SPAD foram realizadas em três épocas diferentes durante o ciclo vegetativo da planta (7, 15 e 30 dias após a pulverização foliar). No estádio fenológico R1 (início do florescimento) coletou-se uma planta inteira de cada parcela para as análises morfológicas, nutricionais e metabólicas. As duas plantas restantes em cada parcela serviram para analisar os parâmetros de produção. Os principais resultados obtidos para os aminoácidos presentes nas formulações dos produtos, foram o aumento na altura das plantas aos 7 e 15 dias após suas aplicações, quando associados a adubação no solo. Além de atuarem como antiestressantes impedindo a diminuição nos teores de clorofilas através da aplicação de glifosato. Os resultados das análises nutricionais comprovaram a ação quelatizante desses aminoácidos, principalmente para o K, B, Fe e Cu. As melhores respostas através da aplicação dos aminoácidos foram para a atividade da NR, GS e concentração de PTS nas folhas. Tivemos uma redução de lipídeos acumulados nos grãos em função das aplicações com aminoácidos isolados ou em conjunto com adubação. Por outro lado, constatamos um aumento de lipídeos através da aplicação em conjunto com glifosato e adubação. Além dos aminoácidos influenciarem positivamente o armazenamento de proteínas nas sementes quando associados ao glifosato.
The objective of this work was to verify the influence of foliar fertilizer on basis of free amino acids combined with the application of glyphosate and fertilization of soil with P and K on soybean (BRS 255 RR). The evaluations were performed on biometric, nutritional, metabolic and productive parameters using the following variables: Height, SPAD values (chlorophylls), leaf area, biomass (fresh and dry weight of leaves and stems), macronutrients and micronutrients in leaves, activity of nitrate reductase (NR), glutamine synthetase (GS), concentration of total soluble protein (TSP), number of pods, fresh and dry weight of pods, 100 grains average weight, total weight of grains, concentration of lipids and proteins accumulated in the grains. Two experiments were conducted in parallel with the products Ajifol and Flororgan in natural environment using polyethylene pots (20 L). A randomized blocks design was used, where each experimental unit was cultivated with three soybean plants per pot filled with 20 kg of substrate (dystrophic clayey Red Latosol). The soil fertilization with P and K (1,00 and 0,24 g kg-1, respectively) was carried out 30 days before sowing. The applications of Ajifol (1,0 L ha-1), Flororgan (2,5 L ha-1) and glyphosate (0,3 L ha-1) were performed by foliar sprays at the V5 developmental stage, corresponding to 35 days after germination. Samples for height and SPAD were taken at three different times during the vegetative stage of plant (7, 15 and 30 days after foliar spraying). At the phenological stage R1 (early flowering) one entire plant of each plot was collected for morphological, nutritional and metabolic analysis. The remaining two plants were used for analyses of production parameters. The application of amino acids increased plant height after 7 and 15 days after foliar spraying, when associated with soil fertilization. They acted moreover as antistress substances preventing a decrease in the levels of chlorophyll caused by application of glyphosate. Nutritional analysis indicated the formation of chelates of these amino acids mainly with K, B, Fe and Cu. The main effects of amino acids applications were higher for NR, GS and TSP concentrations in leaves. A reduction in lipids accumulated in the seeds through sole application of amino acids, as well as in conjunction with fertilization was identified. On the other hand increasing values were found when the amino acids were associated with both glyphosate and fertilization. The amino acids increased the protein storage in seeds when applied in conjunction with glyphosate.
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28

Orioli, Júnior Valdeci [UNESP]. "Adubação nitrogenada e curva crítica de diluição de nitrogênio para a cultura do milho." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/105164.

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A recomendação da adubação nitrogenada para a cultura do milho deve ser constantemente atualizada, pois com frequência são lançados novos híbridos no mercado. Estes híbridos, normalmente, são mais produtivos e mais exigentes em N. A dificuldade de prever a disponibilidade deste macronutriente às plantas pela análise de solo torna ainda mais complexa a definição da dose de N a se aplicar. Atualmente, a dose de N para a cultura do milho é definida considerando-se o histórico da área e a produtividade esperada, e o estado nutricional da cultura quanto ao N tem sido avaliado por ocasião do pendoamento ou florescimento feminino, por meio da diagnose foliar. No entanto, se a deficiência de N for constatada neste estádio fenológico, não há mais possibilidade de se adotar medidas corretivas. Para contornar este problema pode-se adotar a curva crítica de diluição de N, pois esta permite acompanhar o estado nutricional nitrogenado da cultura em grande parte do seu período de crescimento. Assim, objetivou-se com este trabalho: 1) avaliar os efeitos de doses de N na cultura do milho; 2) subsidiar a recomendação da dose deste nutriente para a cultura e; 3) determinar e validar a curva crítica de diluição de N. Para tanto, foram conduzidos dois experimentos por dois anos agrícolas consecutivos (2009/2010 e 2010/2011) em solos distintos quanto à textura (Latossolo Vermelho eutroférrico argiloso - LVef e Latossolo Vermelho distrófico textura média - LVd). Adotou-se o delineamento experimental em blocos casualizados com seis tratamentos e quatro repetições. Os tratamentos consistiram da aplicação de 0, 60, 100, 140, 200 e 260 kg ha-1 de N. Para atingir os objetivos 1 e 2 avaliaram-se a densidade de massa seca de raiz (DMSR), o índice de área foliar (IAF), a concentração de N na folha, a produção de grãos...
The recommendation of nitrogen for maize crop must be constantly adjusted, because frequently are released new hybrids on the market. These hybrids, normally, are more productive and demand more N. The difficulty to predict this nutrient availability to plants by soil analysis makes more complex the definition of the rate of N to use. Nowadays, the N rate for maize is defined considering the area historical and the expected yield and the N fertilization efficiency has evaluated at tasseling or bolting, by foliar diagnosis. Therefore, if N deficiency is detected at this phenological stage, this is no possibility to adopt corrective measures. To work around this problem it can be adopted the critical nitrogen dilution curve, because it allows to follow the nitrogen nutritional status of the culture in great part of its development. Thus, the objective with this work: 1) evaluate the effects of N addition in maize; 2) subsidize the rate recommendation of this nutrient for the culture and; 3) determinate and validate the critical nitrogen dilution curve. So, there were conducted two experiments for two consecutive years (2009/2010 and 2010/2011) in distinct soil as its textures (clayey and medium texture). It was adopted the experimental design in blocks with six treatments and four replications. The treatments consisted of the application of 0, 60, 100, 140, 200 and 260 kg ha-1 of N. To achieve the objectives 1 and 2 evaluated the dry weight root density (DWRD), the leaf area index (LAI), leaf N concentration, grain yield, number of grains per ear, the mass of 1,000 grains and grain weight per ear. It was found that nitrogen fertilization increased the DWRD, however, only in the first 0.20 m depth. The LAI, the concentration of leaf N, the mass of grains... (Complete abstract click electronic access below)
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29

Orioli, Júnior Valdeci. "Adubação nitrogenada e curva crítica de diluição de nitrogênio para a cultura do milho /." Jaboticabal, 2013. http://hdl.handle.net/11449/105164.

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Orientador: Edson Luiz Mendes Coutinho
Banca: José Eduardo Corá
Banca: Anice Garcia
Banca: Rogério Farinelli
Banca: Paulo Sérgio Pavinato
Resumo: A recomendação da adubação nitrogenada para a cultura do milho deve ser constantemente atualizada, pois com frequência são lançados novos híbridos no mercado. Estes híbridos, normalmente, são mais produtivos e mais exigentes em N. A dificuldade de prever a disponibilidade deste macronutriente às plantas pela análise de solo torna ainda mais complexa a definição da dose de N a se aplicar. Atualmente, a dose de N para a cultura do milho é definida considerando-se o histórico da área e a produtividade esperada, e o estado nutricional da cultura quanto ao N tem sido avaliado por ocasião do pendoamento ou florescimento feminino, por meio da diagnose foliar. No entanto, se a deficiência de N for constatada neste estádio fenológico, não há mais possibilidade de se adotar medidas corretivas. Para contornar este problema pode-se adotar a curva crítica de diluição de N, pois esta permite acompanhar o estado nutricional nitrogenado da cultura em grande parte do seu período de crescimento. Assim, objetivou-se com este trabalho: 1) avaliar os efeitos de doses de N na cultura do milho; 2) subsidiar a recomendação da dose deste nutriente para a cultura e; 3) determinar e validar a curva crítica de diluição de N. Para tanto, foram conduzidos dois experimentos por dois anos agrícolas consecutivos (2009/2010 e 2010/2011) em solos distintos quanto à textura (Latossolo Vermelho eutroférrico argiloso - LVef e Latossolo Vermelho distrófico textura média - LVd). Adotou-se o delineamento experimental em blocos casualizados com seis tratamentos e quatro repetições. Os tratamentos consistiram da aplicação de 0, 60, 100, 140, 200 e 260 kg ha-1 de N. Para atingir os objetivos 1 e 2 avaliaram-se a densidade de massa seca de raiz (DMSR), o índice de área foliar (IAF), a concentração de N na folha, a produção de grãos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The recommendation of nitrogen for maize crop must be constantly adjusted, because frequently are released new hybrids on the market. These hybrids, normally, are more productive and demand more N. The difficulty to predict this nutrient availability to plants by soil analysis makes more complex the definition of the rate of N to use. Nowadays, the N rate for maize is defined considering the area historical and the expected yield and the N fertilization efficiency has evaluated at tasseling or bolting, by foliar diagnosis. Therefore, if N deficiency is detected at this phenological stage, this is no possibility to adopt corrective measures. To work around this problem it can be adopted the critical nitrogen dilution curve, because it allows to follow the nitrogen nutritional status of the culture in great part of its development. Thus, the objective with this work: 1) evaluate the effects of N addition in maize; 2) subsidize the rate recommendation of this nutrient for the culture and; 3) determinate and validate the critical nitrogen dilution curve. So, there were conducted two experiments for two consecutive years (2009/2010 and 2010/2011) in distinct soil as its textures (clayey and medium texture). It was adopted the experimental design in blocks with six treatments and four replications. The treatments consisted of the application of 0, 60, 100, 140, 200 and 260 kg ha-1 of N. To achieve the objectives 1 and 2 evaluated the dry weight root density (DWRD), the leaf area index (LAI), leaf N concentration, grain yield, number of grains per ear, the mass of 1,000 grains and grain weight per ear. It was found that nitrogen fertilization increased the DWRD, however, only in the first 0.20 m depth. The LAI, the concentration of leaf N, the mass of grains... (Complete abstract click electronic access below)
Doutor
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30

Araujo, Vanessa Fernandes. "Utilização de subprodutos de xisto na produção e qualidade de morangos." Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/1194.

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The study aimed to evaluate the influence of solid manure (MBR 34) and leaf (AX) based on shale in the production and quality of strawberry cultivars Camarosa and Camino Real. The experiment was conducted in a private property located at Estrada da Gama, 9th District of Pelotas / RS in the period from May to December 2009. The cultivars were Camarosa and Camino Real, conducted in three rows, spaced 0.30 mx 0.30 m under low tunnels and drip irrigation. For each cultivar experiment was performed with a split-plot design by block, with four replications. The solid manure factor (S) with two levels: presence and absence of 500 kg ha-1 in MBR 34 (particle size 100% <0.3 mm) was allocated in the plot. In the subplot factor was allocated foliar fertilizer (F) with three levels: 0, 12 and 24L ha-1 water shale + 10% Ca (calcium nitrate, 14% N and 18% Ca) + 2% B (boric acid, 17% B). Were also employed two additional treatments (control). The experimental unit of the factor plot consisted of 12 plants. The variables analyzed were number of fruits per plant, fruit weight (yield) per plant, weight per fruit, leaf chlorophyll content, soluble solids, total acidity and herbal compounds, which are, anthocyanins, phenolic compounds and antioxidant activity . Was also performed chemical analysis of soil and foliar. Data were subjected to analysis of variance followed by comparison tests of means or polynomial regression analysis. To cultivate Camarosa, concluded that: the leaf manuring and solid manure did not influence the variables of production and chlorophyll content, it is possible that under the experimental conditions, the high levels of nutrients in the soil did not permit the performance expected for the treatments, the antioxidant activity of fruits was higher in the presence of solid manure, the concentrations of phenolic compounds were reduced according to foliar and anthocyanin contents were not affected by treatments, the content of soluble solids was higher in the presence of solid manure (MBR 34), while the acidity of this variety was not affected by treatments. To cultivate Camino Real, increasing the dose of AX, on average, promoted an increase in mass per fruit, the chlorophyll content were not affected by treatments, the Camino Real cultivar proved to be benefited by the element manganese in the soil, especially in the presence MBR 34; generally the nutrients P, Mn, Ca, Mg, Zn and Cu were positively correlated with the variables of production of this cultivar, the nutrient potassium and manganese were elevated in soil, however, remained on the stalk It is within the proper range, the functional characteristics of strawberry are influenced mainly by adverse conditions of culture medium, the content of soluble solids was higher in the presence of solid manure (MBR 34), while the use of foliar fertilization resulted higher levels with the control that was superior to other treatments in the presence of MBR 34.
O trabalho teve como objetivo avaliar a influência da adubação sólida (MBR 34) e foliar (AX) à base de xisto na produção e na qualidade de morangos das cultivares Camarosa e Camino Real. O experimento foi realizado em uma propriedade particular localizada na Estrada da Gama, 9° Distrito de Pelotas/RS, no período de maio a dezembro de 2009. As cultivares utilizadas foram Camarosa e Camino Real, conduzidas em três linhas, com espaçamento de 0,30 x 0,30 m, sob túnel baixo e irrigação por gotejamento. Para cada cultivar foi efetuado um experimento com delineamento de parcelas divididas por bloco, com quatro repetições. O fator adubação sólida (S), com dois níveis: presença e ausência de 500 kg ha-1 da MBR 34 (granulometria 100% <0,3 mm), foi alocado na parcela. Na subparcela foi alocado o fator adubação foliar (F), com três níveis: 0, 12 e 24L ha-1 de água de xisto + 10% Ca (nitrato de cálcio, 14% de N e 18% de Ca) + 2% B (ácido bórico, 17% de B). Foram utilizados ainda dois tratamentos adicionais (testemunhas). A unidade experimental para o fator em subparcela constituiu-se de 12 plantas. As variáveis analisadas foram número de frutos por planta, massa de fruto (produção) por planta, massa por fruto, teor de clorofila das folhas, sólidos solúveis totais, acidez total titulável e compostos fitoquímicos, sendo eles, antocianinas, compostos fenólicos e atividade antioxidante. Também foi realizada análise química foliar e de solo. Os dados foram submetidos à análise de variância seguida de teste de comparação de médias ou analise de regressão polinomial.. Para a cultivar Camarosa, concluiu-se que: os fatores adubação foliar e adubação sólida não interferiram significativamente nas variáveis de produção e no teor de clorofila; é possível que nas condições do experimento, os elevados teores de nutrientes no solo não tenham permitido o desempenho esperado para os tratamentos; a atividade antioxidante dos frutos foi superior na presença de adubação sólida; os teores de compostos fenólicos foram reduzidos em função da adubação foliar e teores de antocianinas não foram influenciados pelos tratamentos; o teor de sólidos solúveis totais foi superior na presença da adubação sólida (MBR 34), enquanto que a acidez titulável desta cultivar não foi influenciada pelos tratamentos. Para cultivar Camino Real, o aumento da dose de AX, em média, promoveu um incremento da massa por fruto; os teores de clorofila não foram afetados pelos tratamentos; a cultivar Camino Real mostrouse beneficiada pelo elemento manganês no solo, principalmente na presença da MBR 34; de modo geral os nutrientes P, Mn, Ca, Mg, Zn e Cu correlacionaram-se positivamente com as variáveis de produção desta cultivar; os teores dos nutrientes potássio e manganês estavam elevados no solo, entretanto, os níveis foliares mantiveram-se dentro da faixa adequada, características funcionais de frutos de morangueiro são influenciadas principalmente por condições adversas do meio de cultivo; o teor de sólidos solúveis totais foi maior na presença de adubação sólida (MBR 34); enquanto que a utilização da adubação foliar proporcionou teores mais elevados à testemunha que apresentou-se superior aos demais tratamentos na presença da MBR 34.
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31

SANTOS, Rubeni Cunha dos. "Avaliação nutricional e de crescimento incial em altura de espécies arbóreas em sistemas agroflorestais na região de Itaparica, semiárido pernambucano." Universidade Federal Rural de Pernambuco, 2016. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5023.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
This study developed at the Experimental IPA station in Belém de São Francisco - PE, surrounding the Itaparica Reservoir, in Pernambuco semiarid zone, aimed to evaluate the effect of using sediments from Itaparica reservoir and fish pond waste as organic fertilizers and biochar as a soil conditioner and the effect of two spacings, 3 x 2 m and 4 x 2 m, in stimulating the growth of four tree species: two Eucalyptus clones (Eucalytpus urophylla x Eucalytpus tereticornis) angico (Anadenanthera colubrina var. cebil) and aroeira (Myracrodruon urundeuva Allemão), associated or not in agroforestry systems with cowpea and in a silvopastoral system with Tanzania grass. It was used a multivariate statistical method of repeated measures over the time. Measurements were taken every three months after planting (0, 3, 6, 9, 12, 15 and 18 months) in the useful area of the plots (10 plants). The number of permanent plots was 256, distributed in a randomized pattern, with four repetitions, which included control without fertilization and isolated plantations. The two spacing were 4 x 2 m for tree species in the consortium and isolated and 3 x 2 m for the species forest isolated. it was collected samples of leaves for foliar analysis in newly mature harvested from the middle third of the canopy, to determine the nutritional status of four tree species, adopting a completely randomized design in a factorial arrangement 4 x 4 x 2, for the isolated and consortium plantation. The fertilization of the species with organic sources of nutrients at the time and after planting resulted in better growth of tree species and improved the nutritional status of the species, especially in relation to nitrogen. The residues from fish farms ponds and lake sediments appear as good alternatives to fertilization in agroforestry systems, as well as in forestry and agriculture. The smallest spacing (3m x 2m) resulted in higher growth of forest species. Native species (angico and aroeira) appeared to have higher nutritional requirement and, in general, had higher levels of nutrients in the leaves compared to Eucalyptus clones. The nutritional content found in leaves, in different spacing and consontium for angico, aroeira and the clone MA 2000 followed the decreasing order: N> Ca> P> Mg and for clone MA 2001 the sequence was N> Ca> Mg> P. For the different consortia, the sequence for all the species was N> Ca> P> Mg. Consortia with agricultural species and the forage species did not affect height growth of forest species and added value to forest production.
O presente estudo desenvolvido na Estação Experimental do IPA, em Belém do São Francisco - PE, no entorno da Represa de Itaparica, no semiárido pernambucano, objetivou avaliar o efeito do uso de sedimentos do reservatório de Itaparica, resíduos de tanques de piscicultura como fertilizantes orgânicos e do biocarvão como condicionador de solo e o efeito de dois espaçamentos, 3 x 2 m e 4 x 2 m, no estímulo ao crescimento de quatro culturas florestais: dois clones de eucalipto (Eucalytpus urophylla x Eucalytpus tereticornis.), angico (Anadenanthera colubrina var. cebil) e aroeira (Myracrodruon urundeuva Allemão), consorciados ou não em sistemas agrossilvicultural com feijão caupi e em sistema silvipastoril com capim Tanzânia. Utilizou-se o método estatístico multivariado de medidas repetidas de altura a cada três meses após o plantio (0, 3, 6, 9, 12, 15 e 18 meses). O número de parcelas permanentes foi 256, distribuídas de forma inteiramente aleatória, com 4 repetições, que incluíram testemunhas sem adubação e plantios isolados, sendo o espaçamento 4 x 2 m para as culturas florestais em consórcio e isolado e 3 x 2 m para as culturasflorestais em plantio isolado. Usou-se área útil de coleta dos dados com 10 plantas por parcela. Foram feitas análises foliares em folhas recém-maturas colhidas do terço médio da copa, para determinação do estado nutricional das quatro culturas arbóreas, adotando-se o delineamento inteiramente casualizado no esquema fatorial 4 x 4 x 2, para o plantio isolado e para o plantio em consórcio. A adubação das plantas com as fontes orgânicas de nutrientes no momento e após o plantio resultou melhores crescimentos das culturas florestais e melhorou o seu estado nutricional, principalmente em relação ao nitrogênio, sendo que os resíduos de tanques de piscicultura e sedimentos do lago surgem como boas alternativas para adubação em sistemas agroflorestais, bem como em silvicultura e em agricultura. O menor espaçamento (3 m x 2 m) resultou maior crescimento das culturas florestais. As espécies nativas (angico e aroeira) aparentaram maior requerimento nutricional e, em geral, tinham maiores teores de nutrientes nas folhas, em comparação aos clones de eucalipto. Os teores nutricionais encontrados nas folhas, nos diferentes espaçamentos e consórcios, de angico, aroeira e clone MA 2000 seguiram a sequência decrescente: N > Ca > P > Mg e os teores foliares para o Clone MA 2001 apresentaram a sequência N > Ca > Mg > P, enquanto que, nos diferentes consórcios, a sequência dos teores foliares de todas culturas florestais foi N > Ca > P > Mg. Os consórcios com a espécie agrícola e a espécie forrageira não afetaram negativamente o crescimento em altura das espécies florestais e agregaram valor à produção florestal.
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32

Barreto, Norma Danielle Silva. "Utilização de fertilizantes a base de fosfito e micronutrientes na cultura do melão." Universidade Federal Rural do Semi-Árido, 2008. http://bdtd.ufersa.edu.br:80/tede/handle/tede/67.

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Despite the high technology utilized in the melon crop at the Assú-Mossoró fruit producer area, state of Rio Grande do Norte, with respect to most of the nutrients, chiefly the micronutrients, the doses applied are the same as those utilized in regions of completely different edaphoclimatic characteristics, and most of the time defined by the supplier companies. Considering this fact, a study was aimed at to evaluate the response of the melon crop to foliar applied ferlizers containing fosfito and micronutrients. The experiment was carried out on a Red Latossolo Eutrophic soil, at Santa Júlia farm, municipality of Mossoró, utilizing a factorial scheme in randomized complete blocks design with four replications. The tratments were the combinations of fertilizers (Fosfitotal®, Fosfitototal Multielementos® and MicroUFERSA) and doses (0, 0.75, 1.5, 2.25 and 3.0 kg ha-1). The fertilizers were foliar applied prior to the beginning of flowering, through three sprayings at ten days interval. The traits evaluated were number, mean weight, and yield of marketable fruits (domestic and export markets), refuse and total, as well as pulp firmness and thickness, shape ratio, soluble solids content, titratable acidity, and laef nutrient content. Soluble solids content was higher in fruits of plants sprayed with Fosfitotal®, however the contents of P, Mg, Cu, Zn, and Fe decreased with increasing doses of the fertilizer. Plants that received the MicroUFERSA fertilizer had higher Mg, K, P,Cu, Mn, and Zn contents in leaves, which might have caused their higher yields. The highest net income was obtained with MicroUFERSA applied at the rate of 1.50 kg ha-1
Apesar da alta tecnologia utilizada na cultura do melão, no que diz respeito à maioria dos nutrientes, principalmente micronutrientes, as doses aplicadas no pólo fruticultor Assú-Mossoró, estado do Rio Grande do Norte, são as mesmas utilizadas em regiões com características edafoclimáticas completamente diferentes, sendo muitas vezes definidas pelas empresas comercializadoras dos insumos. Em razão disso, foi conduzido um estudo para avaliar a utilização de fertilizantes foliares contendo fosfito e micronutrientes na cultura do melão. O experimento foi conduzido em solo Latossolo Vermelho Eutrófico, em área pertencente à fazenda Santa Júlia, município de Mossoró, utilizando-se um esquema fatorial em blocos completos casualizados com quatro repetições. Os tratamentos consistiram das combinações de fertilizantes (Fosfitotal®, Fosfitototal Multielementos® e MicroUFERSA) e doses (0; 0,75; 1,5; 2,25 e 3,0 kg ha 1). Os fertilizantes foram aplicados via foliar antes do florescimento, através de três pulverizações espaçadas de dez dias. As características avaliadas foram número, peso médio e produtividade de frutos comercializáveis (mercados interno e externo), refugos e totais, bem como firmeza e espessura de polpa, relação de formato, teor de sólidos solúveis, acidez titulável e teor de nutrientes nas folhas. O teor de sólidos solúveis foi maior nos frutos das plantas pulverizadas com Fosfitotal®, mas os teores de P, Mg, Cu, Zn e Fe diminuíram com o aumento das doses deste fertilizante. As plantas de melão submetidas à aplicação de MicroUFERSA apresentaram maiores teores de Mg, K, P, Cu, Mn e Zn, resultando em maiores produtividades. A maior renda líquida foi obtida com a dose 1,50 kg ha-1 de MicroUFERSA
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33

Lopes, Marcos Neves. "Gas exchange and morphophysiology in massai grass under Grazing and fertilized with nitrogen." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7419.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
To evaluate the gas exchange, the biomass flow, the biomass components before and after grazing and the tillering dynamics in massai grass under increasing nitrogen fertilization levels (control - without nitrogen fertilizer; 400; 800 and 1200 kgâha-1âyear-1) under rotational stocking with sheeps in a completely randomized design with measurements repeated in time, this research was carried out. The level of nitrogen for each treatment was divided into two parcels, the first half applied immediately after the animals leave the paddock and the second half applied in rest period half, according to each level assessed. The rest period was set at approximately 1.5 new leaf blades per tiller, as determined in pre-testing when the starting of the experiment, providing a period of 22, 18, 16 and 13 days for the nitrogen levels of 0.0 - control, 400, 800 and 1200 kgâha-1âyear-1, respectively. The technique of "mob-grazing" was used for the realization of grazing, using groups of animals for rapid defoliation (duration from 7 to 11 hours). With the animals grazing, the sward height was monitored with a ruler until they reach the recommended residual canopy height of approximately 15 cm, corresponding to the residual LAI of approximately 1.5. The variables: stomatal conductance, leaf photosynthesis rate, leaf carbon dioxide concentration, photosynthesis/transpiration ratio, chlorophyll relative index and nitrogen sufficiency index revealed positive linear response to the nitrogen fertilization. The nitrogen level 1200 kgâha- 1 âyear-1 presented increment of 92.3% on leaf photosynthesis rate in relation to the control. The leaf temperature and photosynthesis / conductance ratio were reduced with increasing of N levels. The leaf transpiration and total herbage biomass revealed quadratic response with maximum point with increasing of levels N. The leaf elongation rate was increased with the nitrogen levels and the grazing cycle 4 showed lower value in relation to the others. The culm elongation rate was increased with N levels, however it was not influenced by the grazing cycles. The leaf senescence rates before and after grazing were not influenced by nitrogen and were not altered by the grazing cycles. The leaf appearance rate and phylochron showed increasing and decreasing linear response, respectively, with N levels. The leaf average length revealed quadratic response with maximum point with N levels and grazing cycle 4 showed the lowest value for that variable. For each kg Nâha-1âyear-1 was observed increments of 0.161 and 0.1604 kgâha-1âday-1 for the herbage production and herbage accumulation rates, respectively. There was quadratic response for green forage biomass, green leaf biomass, green culm biomass, forage total density, canopy height and alive/senescent material ratio reaching maximum values (5172.9, 4146.3, 1033.9 kgâha-1âcycle-1; 179.1 kgâha-1âcm-1, 36.8 cm, 4.0, respectively) for nitrogen levels of 896; 933.9; 797; 879.2; 751.4 and 1161 kgâha-1âyear-1, respectively. For such variables was observed differences between the grazing cycles studied. The N levels provided increment to the variables: residual tiller population density, residual total herbage biomass, residual green herbage biomass, senescent herbage biomass, residual total herbage density and residual green herbage density. It was observed quadratic response for residual green stem herbage biomass and residual green stem density, reaching maximum values (1,014.4 kgâha-1âcycle-1 and 67.9 kgâha-1âcm-1, respectively) for the N levels of 881 and 872.1 kgâha-1âyear-1, respectively. It was observed quadratic response for the leaf/culm residual ratio and residual biomass quality index, reaching minimum values (0.75; 23%, respectively) for the nitrogen fertilization levels of 707.6 and 679.3 kgâha-1âyear-1, respectively. The grazing cycles influenced the most variables analysed after grazing, except for the residual green herbage biomass, the residual alive/senescent relation and the residual green herbage density. The tiller appearance rate, survival rate and mortality rate, tiller biomass and vegetative tillers/senescent tillers relation was increased with the nitrogen fertilization levels, with the first two rates and tiller biomass ranging between the evaluation periods. There was quadratic response for tillers flowering rate, vegetative tillers population density and reproductive tillers population density reaching maximum values (0.051 tillersâ100 tillers-1âday-1; 4818 and 35 tillersâm-2, respectively) for nitrogen fertilization levels of 613.5; 993.5 and 623.9 kgâha-1âyear-1, respectively. For the flowering rate and reproductive tillers population density was observed zifferences between the evaluation periods. The nitrogen fertilization promotes positive responses on gas exchange and morphophysiology of massai grass, recomending aplication of this nutrient up to 934 kgâha-1âyear-1. The grazing cycles promote little changes in the morphophysiological traits of massai grass, when a rigorous grazing management is adopted.
Objetivou-se avaliar as trocas gasosas, o fluxo de biomassa, a estrutura e os componentes da biomassa no prà e pÃs-pastejo e a dinÃmica de perfilhamento em capim-massai submetido a crescentes doses de nitrogÃnio (controle - sem nitrogÃnio; 400; 800 e 1200 kgâha-1âano-1) e sob lotaÃÃo rotativa com ovinos, num delineamento inteiramente casualizado com medidas repetidas no tempo. A dose de nitrogÃnio para cada tratamento foi dividida em duas parcelas, sendo a primeira metade aplicada logo apÃs a saÃda dos animais do piquete e a segunda metade aplicada na metade do perÃodo de descanso, de acordo com cada dose avaliada. O perÃodo de descanso adotado foi de aproximadamente 1,5 novas folhas por perfilho, conforme determinaÃÃo em prÃ-ensaio quando do inÃcio da instalaÃÃo do experimento, propiciando um intervalo de 22; 18; 16 e 13 dias para as doses de nitrogÃnio de 0,0 â controle; 400; 800 e 1200 kgâha-1âano-1, respectivamente. A tÃcnica de âmob-grazingâ foi usada para a realizaÃÃo dos pastejos, empregando-se grupos de animais para desfolhaÃÃes rÃpidas (duraÃÃo de 7 a 11 horas). à medida que os animais pastejavam, a altura do pasto foi monitorada com auxÃlio de uma rÃgua, atà que o dossel atingisse a altura residual preconizada de aproximadamente 15 cm, correspondendo ao IAF residual de saÃda dos animais do piquete de aproximadamente 1,5. As variÃveis: condutÃncia estomÃtica, taxa de fotossÃntese foliar, concentraÃÃo interna de CO2, relaÃÃo fotossÃntese/transpiraÃÃo, Ãndice relativo de clorofila e Ãndice de suficiÃncia de nitrogÃnio responderam de forma linear crescente ao incremento nas doses de nitrogÃnio. Verificou-se aumento de 92,3% na taxa de fotossÃntese para a dose de nitrogÃnio de 1200 kgâha-1âano-1 em relaÃÃo à ausÃncia de nitrogÃnio. A temperatura da folha e a relaÃÃo fotossÃntese/condutÃncia foram reduzidas com o aumento nas doses de nitrogÃnio. A adubaÃÃo nitrogenada proporcionou resposta quadrÃtica com ponto de mÃxima sobre a taxa de transpiraÃÃo foliar e produÃÃo de biomassa de forragem total. A taxa de alongamento foliar respondeu crescentemente Ãs doses de nitrogÃnio (N) e o ciclo de pastejo 4 revelou valor inferior em relaÃÃo aos trÃs primeiros. A taxa de alongamento das hastes respondeu de forma linear crescente com as doses de N, porÃm nÃo foi influenciada pelos ciclos de pastejo. As taxas de senescÃncia foliar anterior e posterior nÃo foram influenciadas pela adubaÃÃo nitrogenada, nem tampouco foram alteradas com os ciclos sucessivos de pastejo. A taxa de aparecimento foliar e o filocrono foram influenciados somente pela adubaÃÃo nitrogenada, revelando resposta linear crescente e decrescente, respectivamente, com as doses de N. Constatou-se resposta quadrÃtica com ponto de mÃximo para o comprimento mÃdio das folhas com a elevaÃÃo nas doses de N e o ciclo de pastejo 4 apresentou menor valor para a referida variÃvel. Para cada quilograma de Nâha-1âano-1, observou-se incrementos de 0,161 e 0,1604 kgâha-1âdia-1 na taxa de produÃÃo de forragem e de acÃmulo de forragem, respectivamente. Constatou-se resposta quadrÃtica para as variÃveis: biomassa de forragem verde, de lÃmina foliar verde, de colmo verde, densidade total de forragem, altura do dossel e relaÃÃo material vivo/material morto, alcanÃando valores mÃximos (5172,9; 4146,3; 1033,9 kgâha-1âciclo-1; 179,1 kgâha-1âcm-1; 36,8 cm; 4,0; respectivamente) nas doses de N de 896; 933,9; 797; 879,2; 751,4 e 1161 kgâha-1âano-1, respectivamente. Para tais variÃveis, verificou-se oscilaÃÃo entre os ciclos de pastejo estudados. ElevaÃÃo nas doses de nitrogÃnio proporcionou resposta crescente sobre as variÃveis: densidade populacional de perfilhos residual, biomassa de forragem total residual, de forragem verde residual, de forragem morta residual, densidade total de forragem residual e densidade de forragem verde residual. Verficou-se resposta quadrÃtica para a biomassa de colmo verde residual e densidade de colmo verde residual, alcanÃando valores mÃximos (1.014,4 kgâha-1âciclo-1 e 67,9 kgâha-1âcm-1, respectivamente) nas doses de nitrogÃnio de 881 e 872,1 kg âha-1âano-1, respectivamente. Observou-se resposta quadrÃtica para a relaÃÃo lÃmina foliar/colmo residual e Ãndice de qualidade da biomassa residual, alcanÃando valores mÃnimos (0,75; 23%, respectivamente) nas doses de nitrogÃnio de 707,6 e 679,3 kgâha-1âano-1, respectivamente. Os ciclos de pastejo exerceram alteraÃÃes sobre a maioria das variÃveis analisadas no pÃs-pastejo, exceto para a biomassa de forragem verde residual, relaÃÃo material vivo/material morto residual e densidade de forragem verde residual. As taxas de aparecimento, sobrevivÃncia e mortalidade de perfilhos, biomassa do perfilho e relaÃÃo perfilhos vegetativos/perfilhos mortos responderam crescentemente Ãs doses de nitrogÃnio, com as duas primeiras taxas e a biomassa do perfilho variando entre os perÃodos de avaliaÃÃo. Constatou-se resposta quadrÃtica para a taxa de florescimento de perfilhos, densidade populacional de perfilhos vegetativos e densidade populacional de perfilhos reprodutivos, alcanÃando valores mÃximos (0,051 perfâ100 perf-1âdia-1; 4818 e 35 perfâm-2, respectivamente) nas doses de nitrogÃnio de 613,5; 993,5 e 623,9 kgâha-1âano-1, respectivamente. Para a taxa de florescimento e densidade populacional de perfilhos reprodutivos, verificou-se oscilaÃÃo entre os perÃodos de avaliaÃÃo. A adubaÃÃo nitrogenada proporciona respostas positivas sobre as trocas gasosas e morfofisiologia do capim-massai, podendo-se utilizar uma dose de nitrogÃnio de atà 934 kgâha-1âano-1. Os ciclos de pastejo modificam as caracterÃsticas morfofisiolÃgicas da referida forrageira em pequena magnitude, quando se adota um manejo rigoroso do pastejo.
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34

Costa, Reinaldo Adriano. "Fertilizantes minerais e aminoácidos aplicados via foliar na produtividade, desenvolvimento vegetativo e nutrição do cafeeiro." Universidade Federal de Uberlândia, 2009. https://repositorio.ufu.br/handle/123456789/12155.

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The purpose of this work was to evaluate the vegetative development, yield and income, leaves macro and micronutrients content from the Acaiá Cerrado cultivar, trait MG- 1474, cultivated under fertilizers formulations applied over the leaves during the period from 2007 to 2009. The experiment was conducted at Pedra Branca´s Farm, situated at the km 14 by MG265, and has an altitude of 912 m, localized at Uberlândia, in Minas Gerais, Brasil, under Red Oxisol with medium texture. The weather is the type of Aw, with a dry winter and a hot and rainy summer. The experimental delineation used was a randomized block, with three replication and eight treatments, being T1 (Plantin CaB2 + Plantin II), T2 (Plantin CaB2 + Ferty-Mould + Plantin II), T3 (Plantin CaB2 + Ferty- Mould + Plantin II), T4 (Plantin II + Ferty-Mould), T5 (Plantin II), T6 (salt combination), T7 (Plantin CaB2 + Ferty-Mould + Plantin Plus + Plantin II), T8 (control). The planting was done on January 2004, and after three years (coffee plant in formation) there were done the spraying over the leaves. The plots were composed of two rows and eight plant each, space of 0, 8 m between plants and 4, 0 m between rows, having as boarder two plants on each side. Annually, there were measured the yield, coffee plant height, crown and trunk diameter, plagiotrophycal branch length and the number of internodes on the ortotrophycal branch and leaves nutrients content. The coffee leave fertilization did not favored for a higher average plants height, branch diameter, internodes number, and plagiotrophycal branch length on the two seasons evaluated. The use of amino acids on the coffee plant did not contribute for a higher yield and vegetative development, as well as for a higher nutrient concentration on the leaves. The leaves fertilizers Plantin CaB2 + Ferty-Mould + Plantin II, presented higher yields on the two evaluated seasons, although it was no sufficient to differ from control.
Objetivou-se com este trabalho avaliar o desenvolvimento vegetativo, produtividade e renda, teores foliares de macro e micronutrientes no cafeeiro Acaiá Cerrado, linhagem MG-1474, cultivado sob diferentes formulações de fertilizantes aplicados via foliar no período de 2007 a 2009. O experimento foi conduzido na Fazenda Pedra Branca, situada na margem da MG 265, km 14, com uma altitude de aproximadamente 912 m, localizada no município de Uberlândia, em Minas Gerais, Brasil, sob Latossolo amarelo distrófico de textura média. O clima local é do tipo Aw, sendo o inverno seco e o verão quente e chuvoso. O delineamento experimental foi em blocos casualizados, com três repetições e oito tratamentos, sendo T1 (Plantin CaB2 + Plantin II), T2 (Plantin CaB2 + Ferty-Mould + Plantin II), T3 (Plantin CaB2 + Ferty-Mould + Plantin II), T4 (Plantin II + Ferty-Mould), T5 (Plantin II), T6 (combinação de sais), T7 (Plantin CaB2 + Ferty- Mould + Plantin Plus + Plantin II), T8 (testemunha). O plantio foi realizado em janeiro de 2004, e após três anos (café em formação) foram realizadas as aplicações foliares. As parcelas foram constituídas por 2 linhas de 8 plantas em cada, espaçadas de 0,8 m entre plantas e 4,0 m entre linhas, considerando como bordadura 2 plantas em cada extremidade. Anualmente, foram mensurados a produtividade, altura do cafeeiro, diâmetros de copa e de caule, comprimento de ramos plagiotrópicos e número de entrenós no ramo ortotrópico e teores foliares. A adubação foliar no cafeeiro não favoreceu para uma maior altura média de plantas, diâmetro de caule, número de internódios e comprimento de ramos plagiotrópicos nas duas safras avaliadas. O uso de aminoácidos na cultura do café não contribuiu para uma maior produtividade e desenvolvimento vegetativo, bem como, para um maior acúmulo de nutrientes nas folhas. Os fertilizantes foliares Plantin CaB2 + Ferty-Mould + Plantin II, resultaram produtividade maiores nas duas safras, porém não foram suficiente para diferir significamente da testemuha.
Mestre em Agronomia
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35

Antunes, Cristiane Leite [UNESP]. "Fertirrigação nitrogenada por gotejamento e época de aplicação foliar de ácido giberélico 'GA IND.3' em alface americana (Lactuca sativa L.)." Universidade Estadual Paulista (UNESP), 2001. http://hdl.handle.net/11449/93828.

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Com o objetivo de avaliar os efeitos do nitrogênio aplicado ao solo, via fertirrigação por gotejamento, e a aplicação foliar do ácido giberélico (GA3), na nutrição e nos componentes de produção da alface tipo americana, cv. 'Lucy Brown', em cultivo protegido, foi efetuado o presente trabalho. O delineamento experimental utilizado foi o de blocos casualizados em esquema de parcelas subdivididas: quatro doses de nitrogênio (60, 120, 180 e 240 kg de N.ha-1), na parcela, e quatro épocas de aplicação de GA3 (0, 40, 55 e 70 DAS - dias após a semeadura), na subparcela. O ácido giberélico foi aplicado com pulverizador costal de CO2, numa concentração única de 20 mg do ingrediente ativo.L-1 de solução, nas subparcelas nas épocas determinadas. Foram realizadas quatro coletas para avaliação dos parâmetros vegetativos e análise de nutrientes, com intervalos de 15 dias, iniciando-se aos 51 DAS (23 DAT- dias após o transplantio) até 96 DAS (64 DAT). Os trabalhos foram conduzidos na área experimental da Fazenda São Manuel, no município de São Manuel - SP. Não foi observada interação entre a aplicação de nitrogênio e o ácido giberélico nos parâmetros vegetativos avaliados, bem como no teor e acúmulo dos macronutrientes. Contudo, houve influência dos fatores de variação de forma independente nos parâmetros ao longo do ciclo. O nitrogênio é extremamente importante no crescimento e acúmulo de matéria fresca na planta de alface tipo americana e pode ser usado em doses maiores quando há disponibilidade de cálcio e potássio. Tendo sido os melhores resultados alcançados com a dose de 180 kg de N. ha-1. O uso do ácido giberélico (GA3), aos 70 DAS (dias após a semeadura) proporcionou os melhores resultados nos parâmetros relativos ao crescimento. Enquanto a época de aplicação aos 40 DAS, promoveu o desenvolvimento intenso do caule, levando a efeitos... .
With the goal of estimating the nitrogen effects applied on the soil, through fertigation by dripping, and the foliar application of gibberellic acid (GA3), in the nourishment and in the components of Crisphead Lettuce production, cv. 'Lucy Brown', in protected cultivation, this paper was done. The used experimental drawing was made of casual blocks in subdivided portions: four doses de nitrogen (60, 120 180 and 240 kg de N.ha-1), in the portion, and four application times of GA3 (0, 40, 55 e 70 DAS - days after sowing) in the subportion. The gibberellic acid was applied with a costal pulverize machine of CO2, in a unique dose of 20 mg.L-1 of the active ingredient, in the subportions in the specific times. Four collects were done for the evaluation of the vegetative parameters and nutrient analysis, with a 15-days recess, beninning on 51 DAS (23DAT) to 96 DAS (64 DAT). The works were managed in the experimental area of São Manuel Farm, in São Manuel County - SP. It wasn't observed interaction between nitrogen application and the gibberellic acid in the evaluated vegetative characteristics, as well as in the tenor and accumulation of macro-nutrients. However, there was na influence of changing factors in na independent way in the parameters along the cycle. The nitrogen is extremely important in the growth and accumulation of fresh material in the Crisphead lettuce vegetable and it can be used in bigger doses when there is availability of calcium and potassium. These have been the best results got with the dose 180 kg of N.ha-1. The usage of gibberellic acid (GA3), on 70 DAS (days after the sowing) provided the best results in the characteristics related to the growth. As long as the application time on 40 DAS, provided the intense satlk growth, conducing to the depreciatory effects, as the plants arranged in layers, a bigger number of external leaves, and a samller accumulation of fresh... (Complete abstract, click electronic address below).
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36

Janicki, Wlodzimierz S. "Nutrient changes in Norway spruce foliage following diagnostic fertilization." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61162.

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The nutrient status of three Norway spruce (Picea abies L. Karst.) plantations in southwestern Quebec were studied through foliar analysis. At all locations low N and K and marginal Mg foliar concentrations were identified.
Diagnostic fertilization resulted in significantly improved foliar K, N, Ca/K molar ratio and in some cases Mg. The foliage of the treated trees has an improved dark green colour as compared with the controls. From this research it is evident that nutrient deficiencies of N, and K in particular, are showing up in spruce stands in the areas where atmospheric pollution is relatively severe. The use of foliar nutrient concentrations along with evaluation of visual decline symptoms give the best results in assessment of the trees' current nutrient status. Proper diagnostic fertilization, using KNO$ sb3$ and (K,Mg)SO$ sb4$, helped to correct the nutrient disturbances on the calcareous soils of the region, impoverished by former agricultural use. In these soils the balance of Ca with K and Mg is crucial for their proper uptake. The base cations addition enlarged the available P pool, as a result of the improved organic matter decomposition. (Abstract shortened by UMI.)
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37

Schoninger, Evandro Luiz. "Absorção foliar de amônia e produtividade do milho em função da época de aplicação de ureia em cobertura." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/64/64134/tde-05112014-163046/.

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A necessidade da adubação nitrogenada no milho e as perdas significativas de N que podem ocorrer, tanto do solo, como pela folhagem das plantas, são fatores que elevam os custos de produção. Contudo, com a possibilidade de aplicação do N em cobertura em diferentes estádios fenológicos da cultura do milho e, como o N pode ser perdido na forma de amônia e as plantas apresentam a capacidade de absorver NH3 da atmosfera pela folhagem, torna-se interessante a quantificação dessa via de ganho de N nos agrossistemas em diferentes estádios de desenvolvimento das culturas, com a finalidade de proporcionar maior aproveitamento do nutriente pelas plantas. Nesse contexto, objetivou-se: i) avaliar a época de aplicação da ureia em cobertura no milho que proporcione maior aproveitamento do N do fertilizante e produtividade de grãos; ii) mensurar a absorção foliar de NH3 oriunda da ureia aplicada na superfície do solo em diversos estádios fenológicos do milho, e verificar a correlação entre a quantidade de NH3 absorvida e a área foliar da cultura. O estudo foi desenvolvido no bairro rural de Tanquinho, município de Piracicaba, SP, nas safras 2011/12 e 2012/13. Foram desenvolvidos dois experimentos em campo, em delineamento experimental de blocos ao acaso, com quatro repetições. O solo da área experimental é classificado como Latossolo Vermelho Distrófico, manejado em sistema convencional de preparo do solo. No primeiro experimento foi quantificado o aproveitamento do N do fertilizante pela cultura, a produção de fitomassa seca da parte aérea em diversos estádios fenológicos, bem como a produtividade de grãos, em função dos tratamentos testados, a saber: cinco épocas de aplicação de ureia (140 kg ha-1 de N) em cobertura nos estádios fenológicos V4, V6, V8, V10 e V12, e um controle sem adubação de cobertura. No segundo experimento, foi quantificada a área foliar e a absorção da amônia volatilizada da ureia aplicada em bandejas contendo o mesmo solo da área experimental, para que não fosse exposto ao sistema radicular de plantas de milho, em função de cinco tratamentos (épocas de aplicação - idem ao primeiro experimento). Os resultados foram submetidos à análise de variância (p<=0,05) e à comparação das médias pelo teste de Tukey. Não houve diferença entre os tratamentos quanto ao acúmulo de fitomassa seca da parte aérea em todos os estádios fenológicos avaliados. Do mesmo modo, não houve incremento na produtividade de grãos com a aplicação de N em cobertura em diferentes estádios fenológicos. Por outro lado, a aplicação de N em cobertura nos estádios mais precoces (V4 ou V6) proporcionou maior recuperação do N do fertilizante, chegando a valores de 53 %. Na média das duas safras, o nitrogênio volatilizado da ureia que foi absorvido pelas plantas apresentou valores de 3,4, 5,5, 6,2, 9,0 e 14,8 %, respectivamente, nos estádios V4, V6, V8, V10 e V12; aproximadamente 90 % do N absorvido pela folhagem foram acumulados nas folhas e apenas 10 % nos colmos. Houve alta correlação entre a área foliar e a porcentagem de amônia absorvida pelas folhas (r = 0,93, p<=0,05). Isto ocorreu porque a área foliar representa a superfície de contato da planta com a amônia da atmosfera, confirmando a hipótese de que a maior área foliar reflete em maior absorção foliar percentual de amônia
The need for nitrogen fertilization of corn crop and the significant losses of N that can occur both from soil and plants foliage are factors that increase production costs. However, with the possibility of sidedress application of N at different corn growth stages and considering that N can be lost as ammonia, and that plants have the capacity to uptake NH3 from the atmosphere by the foliage, it is interesting to measure this pathway of N uptake in agricultural systems in different stages of crop development, in order to provide greater N fertilizer recovery by plants. In this context, this study aimed to: i) evaluate the urea sidedress timing in corn that provides the greater N fertilizer recovery and grain yield; ii) measure the foliar uptake of NH3 volatilized from urea applied on the surface at different corn growth stages, and to evaluate the correlation between the amount of NH3 absorbed and corn leaf area. The study was performed in Piracicaba, State of São Paulo, during the growth seasons of 2011/12 and 2012/13. Two field experiments were performed in experimental design of randomized blocks with four replications. The soil of experimental area is classified as Rhodic Haplustox, cultivated under conventional tillage system. In the first experiment, N fertilizer recovery by crop, dry matter yield in different growth stages and grain yield were evaluated as a function of five urea sidedress timing (140 kg ha-1 N), represented by growth stages V4, V6, V8, V10 and V12, and a control without N application. In the second, leaf area was measured and the absorption of volatilized ammonia from urea applied in trays containing the same soil of the experimental area, to avoid that N was exposed to the corn roots, according to five treatments (application times - same as the first experiment). The data were submitted to analysis of variance (p<=0.05) and comparison of means by Tukey test. There was no difference among treatments for dry matter accumulation of shoots in all growth stages. Similarly, there was no increase in grain yield with the N application at different growth stages. However, the N application in the early stages (V4 or V6) provided greater N fertilizer recovery, reaching values of 53 %. In average, the nitrogen volatilized recovered by plants presented values of 3.4, 5.5, 6.2, 9.0 and 14.8 %, respectively, in V4, V6, V8, V10 and V12; approximately 90 % of N absorbed by foliage were retained in the leaves and only 10 % in the stalks. There was a high correlation between leaf area and the percentage of ammonia absorbed by the leaves (r = 0.93, p<=0.05). This occurred because the leaf area is the contact surface of the plant with atmospheric ammonia, confirming the hypothesis that the greater leaf area reflects in greater percentage of leaf ammonia absorption
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38

Nogueira, Lais Meneghini [UNESP]. "Doses e modos de aplicação de Boro e adubação com Zinco na cultura do milho." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138268.

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As deficiências de boro (B) e zinco (Zn) comumente ocorrem em solos de Cerrado. Por isso, para obtenção de maiores produtividades de milho é necessário entender melhor a interação desses elementos, como se existe efeito sinérgico ou antagônico na absorção destes micronutrientes do solo, tal como o modo de aplicação mais vantajoso (via solo ou foliar) e o efeito residual destas adubações. Sendo assim, objetivou-se avaliar o efeito de doses de B aplicadas via solo e via foliar, ambos com ou sem adubação com Zn no solo sobre o estado nutricional, componentes de produção e produtividade do milho primavera/verão e o residual destas adubações via solo no milho outonal, em solo de Cerrado com baixo teor de boro. O experimento foi desenvolvido em um Latossolo Vermelho distrófico em sistema plantio direto. O delineamento experimental dos dois experimentos foi em blocos ao acaso com quatro repetições, dispostos em esquema fatorial 2 x 5, sendo: com ou sem adubação via solo com 2 kg ha-1 de Zn, na forma de sulfato de zinco aplicados na ocasião da semeadura do milho primavera/verão; e 5 doses de B (0, 1, 2, 3 e 4 kg ha-1 na semeadura do milho primavera/verão (experimento 1) ou 0, 170, 340, 510 e 680 g ha-1, que correspondem respectivamente, 0; 0,25; 0,50; 0,75 e 1% de ácido bórico na calda de pulverização aplicada via foliar na fase de pré-pendoamento do milho (experimento II). Após a colheita do milho primavera/verão, avaliou-se o residual destes tratamentos aplicados via solo no cultivo do milho outonal e foram aplicados novamente as doses de B via foliar no milho outonal, conforme mencionado anteriormente. A aplicação de Zn no solo propicia maiores teores de Zn no solo e B foliar no milho primavera/verão, independentemente da dose de B aplicada via foliar. Doses crescentes de B via foliar aumentam o teor de Zn nos grãos do milho primavera/verão, apenas quando não se adubou com Zn, e o teor de B foliar do milho outonal. A adubação com zinco no solo e o incremento das doses de boro tanto via solo como foliar não influenciam os componentes de produção e produtividade de grãos de milho primavera/verão e outonal, em solo argiloso de Cerrado com baixo teor de B.
Boron deficiencies (B) and zinc (Zn) commonly occur in Cerrado soils. Thus, for obtaining higher maize yields is necessary to better understand the interaction of these elements, as if exists synergistic or antagonistic effect on the absorption of these micronutrients in soil, such as the most advantageous mode of application (by soil or foliar) and the effect of these residual fertilizations. Therefore, it was aimed to evaluate the effect of B rates applied to soil (experiment I) and foliar application (experiment II), both with or without Zn fertilization in the soil on nutritional status, yield components and grains yield of spring/summer maize and the residual of these fertilizations in the soil in the autumnal maize, in Cerrado soil with low boron content. The experiment was conducted in an Oxisol under notillage system. The experimental design of the two experiments was a randomized block with four replications, in a factorial 2 x 5, being: with or without soil fertilization with 2 kg ha-1 Zn, in the form of zinc sulfate applied on the occasion of sowing of spring/summer maize; and 5 doses of B (0, 1, 2, 3 and 4 kg ha-1 applied at sowing of spring/summer maize (experiment 1) or 0, 170, 340, 510 and 680 g ha-1 , which correspond respectively, 0, 0.25, 0.50, 0.75 and 1% of boric acid in the spray solution applied by foliar in pre-tasseling of maize (experiment II)). After harvesting of the spring/summer maize was evaluated the residual of these treatments applied to the soil in the cultivation of autumnal maize and were applied again the B rates as foliar application in autumnal maize, as mentioned earlier. The application of Zn in soil propitiates higher contents of Zn in soil and B foliar in spring/summer maize, regardless of B rate applied as foliar application. Increasing B rates, as foliar application increase the Zn content in the grains of spring/summer maize, only without Zn fertilization, and the B leaf content of autumnal corn. The zinc fertilization in the soil and increasing boron rates in the soil and by foliar application not influence the production components and grains yield of spring/summer and autumnal maize, in clay soil of the Cerrado with low B content
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39

Liu, Ge 1961. "Effects of soil fertility and time on the leaf physiology of sugar maple in relation to forest decline." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61218.

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Two studies were conducted to assess physiological responses of declining sugar maple (Acer saccharum Marsh.) in southern Quebec to wet acidic precipitation and increased soil fertility. Leaves of sugar maple were relatively acidic, had low external neutralization capacity (ENC = 5.1 $ mu$equiv. H$ sp{+} rm g sp{-1}$) and buffering capacity index (BCI = 103 $ mu$equiv. H$ sp{+} rm g sp{-1}$), and higher ENC/BCI compared to three other tree species. Deciduous species showed a higher BCI and a lower ENC in August. Our results suggest that sugar maple may be relatively sensitive to wet acidic deposition and that leaf buffering capacity is related to photosynthesis potential and seasonal change in foliar Ca concentration. Foliar analyses revealed that fertilization with a mixture of K, Ca, and Mg had significant effects on leaf concentrations of K, free amino acids (FAA) and the ratios of N to K, and FAA to N after two growing seasons. Our results suggest that base cation fertilization improved the N and K status of sugar maple and that leaf carbon partitioning appeared to be more dynamic in fertilized trees.
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40

Wilsdorf, Robert Ernst. "Evaluating the seasonal changes in calcium concentration and distribution in apple fruit after application of different calcium fertilisation strategies." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17790.

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Thesis (MScAgric)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: Localized calcium (Ca) deficiencies frequently develop independent from total Ca supply and total fruit Ca concentration. Bulk mineral analyses is therefore not completely suitable for determination of the susceptibility of fruit in developing Ca-linked fruit physiological disorders like bitter pit, as it supplies insufficient information regarding the spatial accumulation of Ca within the fruit. Additional Ca is applied either as soil or foliar applications, where soil applications are applied either after fruit set (pre-harvest) or in the period after harvest. The contribution of these different methods of Ca application to the total Ca concentration in "Braeburn" fruit was quantified over three consecutive growing seasons. Foliar applications have been proven to be successful in suppressing bitter pit development and improving the Ca status of the fruit. The effectiveness of different formulations of foliar Ca products in influencing these parameters was also determined. Furthermore, the distribution pattern of fruit Ca resulting from different application strategies was mapped using particle induced X-ray emission technology. In the "Braeburn" trial, mineral analyses indicated no significant differences between treatments in terms of Ca concentration at 80 days after full bloom (dafb). However, when soil applications occurred with active root growth (visually monitored), treatments differed significantly 80 dafb. Weekly foliar Ca applications from 28 dafb resulted in higher fruit Ca concentrations 80 dafb than a pre-harvest soil Ca application (January, 2010). A possible explanation for the inefficiency of pre-harvest soil Ca is the disintegration of xylem vessels from 40 dafb (before root uptake) for sensitive cultivars such as Braeburn. Bitter pit initiation has been shown to occur in the earlier part of the season. This, together with a reduced Ca supply to the fruit early in the season due to xylem disintegration (for sensitive cultivars), indicates the importance of early season foliar Ca applications. PIXE analyses were used to establish the radial Ca distribution in apples. Ca was concentrated in the skin and core, with very low values in the outer cortex. PIXE results indicated fruit Ca concentrations to be the lowest in the pre-harvest soil application treatment. This was in agreement with mineral analyses results. Ca enriched areas resulting from effective Ca delivery via the vascular bundles, had a profound effect on fruit Ca concentrations in the immediate core and cortex. At harvest, this effect was much more subtle and emphasizes the importance of untimely xylem rupturing on eventual fruit Ca concentration. At 80 dafb, treatments where foliar Ca was applied showed higher Ca concentrations in the outer cortex (where symptoms of bitter pit typically occur). Calflo™ fruit had significantly higher Ca concentrations in "Braeburn" compared to fruits from Foliar GS™ and GG™ treatments. Calflo™ and Calcimax™ had a higher active Ca percentage (12%) compared to Foliar GSTM and GGTM (10%). Adding the Lecithin™ (surfactant) to Calcimax™ is not recommended as it did not improve its uptake. In "Golden Delicious", the commercial spray program of seven, weekly foliar applications (Calcinit™) resulted in fruit with significantly higher Ca concentrations compared to other treatments.
AFRIKAANSE OPSOMMING: Kalsium (Ca) tekorte ontstaan gewoonlik in gelokaliseerde areas in die appelvrug en ontwikkel dikwels ten spyte van voldoende totale vrug Ca. Minerale analises van heel vrugte verskaf dus nie genoeg inligting aangaande die verspreiding van Ca in die vrug wanneer die ontwikkelling van fisiologiese defekte soos bitterpit ter sprake is nie. Addisionele Ca word gewoonlik aangewend as blaar- of grondtoedienings, waar grondtoedienings tipies voor-oes (net na set) of in die na-oes periode, toegedien word. Die bydraes van die verskillende toedieningsmetodes tot die totale Ca konsentrasie van "Braeburn" appels is geëvalueer oor drie agtereenvolgende seisoene. Blaartoedienings van Ca word algemeen gebruik om die voorkoms van bitterpit te beheer en die Ca konsentrasie van die vrug te verhoog. Die effektiwiteit van `n reeks blaartoedienings-produkte om hierdie faktore te verbeter, is ook ondersoek. Die spesifieke verspreiding van die Ca in die vrug is gekarteer na gelang van elke toediening deur middel van PIXE-analises (Particle induced X-ray emission). In die "Braeburn" proef was daar geen beduidende verskille in terme van vrug Ca konsentrasie op 80 dnvb (dae na volblom) nie. Daarteenoor, was daar wel beduidende verskille by 80 dnvb toe grond toedienings saam met aktiewe wortelgroei geskied het (visuele inspeksie). Weeklikse blaartoedienings vanaf 21 dnvb het gelei tot vrugte met betekenisvol hoër Ca konsentrasies as die behandeling waar grondtoedienings slegs voor-oes geskied het (Januarie 2010). `n Moontlike oorsaak vir die oneffektiwiteit van voor-oes grondtoedings is die vroeë disintigrasie van xileem vesels in die vrug (soms voor 40 dnvb en voor die aanvang van wortelopname) in sensitiewe kultivars soos "Braeburn". Hierdie vroeë inhibering van Ca voorsiening, tesame met die vroeë inisiasie van bitterpit, beklemtoon die belangrikheid van blaarbespuitings vroeg in die seisoen. Die PIXE-analises wat aangewend is om die radiale verspreiding van Ca in die vrug te bepaal het getoon dat Ca meestal in die skil en kern van die vrug gekonsentreer was, met baie lae konsentrasies in die buitenste korteks. Die laagste Ca konsentrasies is waargeneem in vrugte van die behandeling waar voor-oes Ca slegs as `n grondtoediening geskied het. Hierdie waarneming is in ooreenstemming met die mineraalanalise resultate. Ca verykte areas, afkomstig van die naby geleë vaatbundels (xileem vesels), het egter die grootste effek op vrug Ca konsentrasie gehad. Hierdie effek was nie so groot by oes nie en beklemtoon dus die belangrikheid van die funksionaliteit van die vaatbundels. Blaartoedienings kon die Ca konsentrasie in die buitenste korteks suksesvol verhoog - waar simptome van bitterpit tipies voorkom. Die Calflo™ behandeling het beduidende hoër Ca konsentrasies gehad as die Foliar GS™ en GG™ behandelings. Die Calflo™ en Calcimax™ behandelings het `n hoër aktiewe Ca persentasie (12%) relatief tot die Foliar GS™ en GG™ (10%) behandelings bevat. Die byvoeging van Lecithin™ by Calcimax™ word nie aanbeveel nie, omdat dit geensins Ca opname vermeerder het nie. In die "Golden Delicious" proef het die kommersiële behandeling (Sewe weeklikse spuite van Calcinit™) gelei tot vrugte met die hoogste Ca konsentrasie van al die behandelings.
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41

Chater, John Matthew. "THE EFFECTS OF FOLIAR NUTRIENT APPLICATIONS ON SPLIT, YIELD, AND INTERNAL FRUIT QUALITY OF 'WONDERFUL' POMEGRANATE (PUNICA GRANATUM L.)." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1510.

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Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO4 (3000 mg∙L-1, 4000 mg∙L-1, or 5000 mg∙L-1), MgSO4 (1%, 2%, or 3%), KNO3 (1%, 2%, or 3%), or deionized (DI) water (control). Fruit were analyzed for fruit split incidence, yield, fruit number per tree, fruit diameter, fruit mass, mass of all arils in fruit, mass of 100 arils, total soluble solids (TSS), titratable acidity (TA), antioxidant activity (AA), total phenolics (TP), and mineral nutrient concentrations of leaves and fruit. Foliar applications of MgSO4 and ZnSO4 resulted in significantly lower fruit split incidence. Treatments had no significant effect on fruit number per tree, fruit diameter, and mass, mass of all arils in fruit, or mass of 100 arils. Leaf N, K, S, Mn, and Zn were significantly affected by the treatments. TSS and TA were not affected significantly by treatments. AA ranged from 77.8-84.3 percent inhibition of 2,2’-diphenyl-1-picrylhydrazyl and TP ranged from 2489-3046 mg·L-1 gallic acid equivalents, with some KNO3 treatments significantly affecting these parameters. Fruit mineral nutrient concentrations were characterized and Zn-treated trees had greater fruit Zn concentrations. The results suggest that foliar ZnSO4 or MgSO4 could be used to decrease fruit split incidence and increase nutritional content of ‘Wonderful’ pomegranate and any of the three tested foliar nutrients could be applied as a foliar fertilizer without negatively impacting fruit yield, size, internal quality, bioactivity, or mineral nutrient concentration.
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42

Munareto, Janete Denardi. "Aspectos fisiológios de sementes, produtividade de grãos de trigo submetidos a doses de nitrogênio, inoculação e aplicação foliar de Azospirillum brasilense." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/5171.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The use of chemical fertilizers as well as providing greater productivity, is costly. The use of bacteria of the genus Azospirillum brasilense represent a potential tool to reduce production costs while improving productive potential of crops using environmental resources. It is also known that the search for an increasingly sustainable and productive agriculture is increasingly discussed, and within that reality, we seek new technologies to improve the producer's profit margin. Within this context, the objective of this research was to evaluate the wheat yield, inoculated or not with A. brasilense, subjected to N rates, seed treatment and physiological quality of the seeds. Chapter I aimed to evaluate the compatibility of Azospirillum brasilense bacteria fungicide (difenoconazole) and insecticide (thiamethoxan), and physiological quality in wheat seeds. The wheat seed retains its quality when it checks the germination, vigor and independent accelerated aging grow, use or not of fungicide, insecticide and Azospirillum brasilense. The insecticide thiamethoxam increased the length of shoot and root and provides compatibility with Azospirillum brasilense and fungicide inhibits the length of shoot and root and is antagonistic bacterium A. brasilense. In Chapter II objective was to evaluate the agronomic performance of wheat cultivars submitted to nitrogen doses and inoculation of Azospirillum brasilense in seed and foliar application. Inoculation foliar alone or jointly via seed treatment increased grain yield and other yield components of all cultivars. Among the cultivars tested the TBIO Sinuelo stood out, with inoculation response in the two years of study, confirming the good potential of the leaf inoculation.
O uso de fertilizantes químicos além de proporcionar maior produtividade, é oneroso. A utilização de bactérias do gênero Azospirillum brasilense representam uma ferramenta potencial para reduzir os custos de produção, e ao mesmo tempo melhorar o potencial produtivo das culturas utilizando os recursos do meio. Sabe-se ainda que a busca por uma agricultura cada vez mais sustentável e produtiva é cada vez mais discutida, e dentro dessa realidade, busca-se novas tecnologias para melhorar a margem de lucro do produtor. Dentro deste contexto, o objetivo dessa pesquisa foi avaliar a produtividade do trigo, inoculada ou não com A. brasilense, submetido a doses de N, tratamento de sementes e qualidade fisiológica de suas sementes. O capítulo I teve por objetivo avaliar a compatibilidade da bactéria Azospirillum brasilense com fungicida (difenoconazole) e inseticida (thiamethoxan), e a qualidade fisiológica, em sementes de trigo. A semente de trigo mantém a sua qualidade quando se verifica a germinação, vigor e o envelhecimento acelerado independente da cultivar, utilização ou não de fungicida, inseticida e Azospirillum brasilense. O inseticida thiamethoxam aumenta o comprimento da parte aérea e raiz e apresenta compatibilidade com o Azospirillum brasilense e o fungicida inibe o comprimento da parte aérea e raiz e é antagônico a bactéria A. brasilense. No capítulo II objetivo foi avaliar o desempenho agronômico de cultivares de trigo submetidas a doses de N e inoculação de Azospirillum brasilense em sementes e aplicação foliar. A inoculação via foliar de forma isolada ou de forma conjunta via tratamento de sementes, aumentaram a produtividade de grãos e os demais componentes de produtividade de todas as cultivares. Dentre as cultivares testadas a TBIO Sinuelo se destacou, apresentando resposta de inoculação nos dois anos de estudos, confirmando o bom potencial da inoculação foliar.
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Antunes, Cristiane Leite. "Fertirrigação nitrogenada por gotejamento e época de aplicação foliar de ácido giberélico 'GA IND.3' em alface americana (Lactuca sativa L.) /." Botucatu : [s.n.], 2001. http://hdl.handle.net/11449/93828.

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Orientador: Antônio de Pádua Sousa
Banca: Roberto Lyra Villas Bôas
Banca: Tarlei Arriel Botrel
Resumo: Com o objetivo de avaliar os efeitos do nitrogênio aplicado ao solo, via fertirrigação por gotejamento, e a aplicação foliar do ácido giberélico (GA3), na nutrição e nos componentes de produção da alface tipo americana, cv. 'Lucy Brown', em cultivo protegido, foi efetuado o presente trabalho. O delineamento experimental utilizado foi o de blocos casualizados em esquema de parcelas subdivididas: quatro doses de nitrogênio (60, 120, 180 e 240 kg de N.ha-1), na parcela, e quatro épocas de aplicação de GA3 (0, 40, 55 e 70 DAS - dias após a semeadura), na subparcela. O ácido giberélico foi aplicado com pulverizador costal de CO2, numa concentração única de 20 mg do ingrediente ativo.L-1 de solução, nas subparcelas nas épocas determinadas. Foram realizadas quatro coletas para avaliação dos parâmetros vegetativos e análise de nutrientes, com intervalos de 15 dias, iniciando-se aos 51 DAS (23 DAT- dias após o transplantio) até 96 DAS (64 DAT). Os trabalhos foram conduzidos na área experimental da Fazenda São Manuel, no município de São Manuel - SP. Não foi observada interação entre a aplicação de nitrogênio e o ácido giberélico nos parâmetros vegetativos avaliados, bem como no teor e acúmulo dos macronutrientes. Contudo, houve influência dos fatores de variação de forma independente nos parâmetros ao longo do ciclo. O nitrogênio é extremamente importante no crescimento e acúmulo de matéria fresca na planta de alface tipo americana e pode ser usado em doses maiores quando há disponibilidade de cálcio e potássio. Tendo sido os melhores resultados alcançados com a dose de 180 kg de N. ha-1. O uso do ácido giberélico (GA3), aos 70 DAS (dias após a semeadura) proporcionou os melhores resultados nos parâmetros relativos ao crescimento. Enquanto a época de aplicação aos 40 DAS, promoveu o desenvolvimento intenso do caule, levando a efeitos... (Resumo completo, clicar acesso eletrônico abaixo).
Abstract: With the goal of estimating the nitrogen effects applied on the soil, through fertigation by dripping, and the foliar application of gibberellic acid (GA3), in the nourishment and in the components of Crisphead Lettuce production, cv. 'Lucy Brown', in protected cultivation, this paper was done. The used experimental drawing was made of casual blocks in subdivided portions: four doses de nitrogen (60, 120 180 and 240 kg de N.ha-1), in the portion, and four application times of GA3 (0, 40, 55 e 70 DAS - days after sowing) in the subportion. The gibberellic acid was applied with a costal pulverize machine of CO2, in a unique dose of 20 mg.L-1 of the active ingredient, in the subportions in the specific times. Four collects were done for the evaluation of the vegetative parameters and nutrient analysis, with a 15-days recess, beninning on 51 DAS (23DAT) to 96 DAS (64 DAT). The works were managed in the experimental area of São Manuel Farm, in São Manuel County - SP. It wasn't observed interaction between nitrogen application and the gibberellic acid in the evaluated vegetative characteristics, as well as in the tenor and accumulation of macro-nutrients. However, there was na influence of changing factors in na independent way in the parameters along the cycle. The nitrogen is extremely important in the growth and accumulation of fresh material in the Crisphead lettuce vegetable and it can be used in bigger doses when there is availability of calcium and potassium. These have been the best results got with the dose 180 kg of N.ha-1. The usage of gibberellic acid (GA3), on 70 DAS (days after the sowing) provided the best results in the characteristics related to the growth. As long as the application time on 40 DAS, provided the intense satlk growth, conducing to the depreciatory effects, as the plants arranged in layers, a bigger number of external leaves, and a samller accumulation of fresh... (Complete abstract, click electronic address below).
Mestre
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44

Costa, Flávio Murilo Pereira da. "Severidade de Phaeosphaeria maydis e rendimento de grãos de milho (Zea mays L.) em diferentes ambientes e doses de nitrogênio." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-02072002-115459/.

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O manejo da cultura de milho (Zea mays L.) tem incorporado os recentes avanços tecnológicos em agricultura, o que tem proporcionado aumentos significativos de rendimento. Procedimentos relativos à redução da severidade de doenças, como a causada por Phaeosphaeria maydis, tornam-se prementes. O fungo é um agente biótico que promove redução de produtividade. Tal fato está relacionado com o estresse da planta, com a severidade da doença e com as condições climáticas, principalmente umidade relativa e temperatura do ar. A ênfase da pesquisa é a de nortear mais detalhadamente as ações de manejo levando em consideração esses fatores, estabelecendo técnicas culturais racionais quando da utilização de genótipos susceptíveis. Por outro lado, mesmo utilizando genótipos tolerantes, um manejo nutricional inadequado da cultura sob condições climáticas favoráveis à doença, pode ser constatada a incidência de P. maydis com maior severidade. Sendo assim, com o objetivo de avaliar cinco diferentes genótipos de milho, sendo quatro tolerantes a P. maydis e um susceptível, foram conduzidos ensaios em quatro épocas de semeadura, as duas primeiras no campus "Luiz de Queiroz" (Local 1) e as duas últimas na Estação Experimental de Anhembi (Local 2), ambos no município de Piracicaba, sob a influência de cinco doses de nitrogênio (0; 60; 120; 180 e 240 kg/ha). De acordo com os resultados obtidos, concluiu-se que: (i) o desempenho do genótipo é dependente da época de Semeadura, e a adubação nitrogenada propicia aumento no rendimento de grãos apenas quando a condição ambiental não é limitante; e (ii) a severidade de P. maydis é dependente da época de semeadura, da dose de nitrogênio e do material genético. O estresse da planta provocado por elevadas temperaturas predispõe a cultura à incidência da doença com maior severidade.
Maize (Zea mays L.) crop management is incorporating the ultimate technological advances in Agriculture, resulting in higher yield. Procedures to reduce diseases severity, as those caused by Phaeosphaeria maydis, are becoming more important. The fungus is a biotic agent that reduces productivity due to plant stress. This is related to disease severity and climatic conditions, mainly air temperature and relative humidity. The research had the emphasis of getting better orientation for management actions, using rational agricultural techniques when susceptible genotypes are used. Under favorable climatic condition for P. maydis, the inadequate crop nutritional management results in higher severity even using tolerant genotypes. Therefore, with the purpose of evaluating five different maize genotypes (four tolerant and one susceptible to P. maydis), the field experiments were carried out in four sowing dates, the first two at "Luiz de Queiroz" campus (Location 1) and the last two at Anhembi Experimental Station (Location 2), both in Piracicaba county, São Paulo State, Brazil, making four environments, all under the influence of five nitrogen doses (0; 60; 120; 180 e 240 kg/ha). According to the results, we concluded: (i) the genotype performance depends on the sowing date, and the nitrogen fertilization increases grain yield only without environmental limitation to plant growth; and (ii) the P. maydis severity depends on the sowing date, nitrogen fertilization dose and genotype susceptibility. The stress caused by high air temperature results in higher severity incidence of P. maydis.
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45

Hundley, Christopher Alan. "Evaluation of organophosphate insecticides on performance of transgenic and conventional cotton." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/2189.

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Genetically modified cotton (Gossypium hirsutum L.) acreage has increased dramatically over the last six years. Reports of variable results in fiber quality and yield have arisen in these cultivars. Some changes in production practices have occurred coincident with the introduction of transgenic technology, such as reduced use of broad-spectrum insecticides, including organophosphates (OP) that could potentially influence the growth and yield of cotton. One factor that might affect these parameters is the difference in the amount of foliarly-applied phosphorus (P) between an OP and non-phosphate (NP) insecticide regime. Therefore, a study was conducted to investigate selected growth characteristics, yield, and fiber quality of genetically modified and conventional cotton as influenced by OP and foliar phosphorus (FP) applications. A four replication strip-plot experimental design was utilized with cultivar serving as the whole plot and insecticide regime as the sub-plot. Three cultivars of the same recurrent parent (ST4892BR, ST4793R, and ST474) were planted in 2001 and 2002 under irrigated conditions in Burleson County, TX on a Weswood silty clay loam (fine-silty, mixed, thermic Fluventic Ustochrept). The insecticide regime consisted of NP, NP+FP, and OP treatments. The FP was applied at P2O5 weight equivalent to the P component in the concurrent OP application. ST4892BR had greater lint yield than ST4793R and ST474. The yield increase can be explained through plant mapping analysis which showed ST4892BR producing larger bolls and greater boll numbers. In addition, evaluation of fruiting distribution showed ST4892BR contained more lint on sympodial branches 6 through 10. The insecticide regime effect on lint yield resulted in higher yield (P=0.08) for the NP+FP regime. Examination of yield components revealed NP+FP increased second position bolls, predominantly at sympodial branches 6 through 10. Leaf tissue analysis revealed increased levels of P for the OP and NP+FP over that of the NP insecticide regime, which indicates a potential for plants to acquire P from OP insecticides. Furthermore, the considerable yield response to small amounts of FP is not clearly understood. While conclusive evidence exists regarding cultivar yield differences, this study does not provide sufficient evidence to conclude that OP insecticides influence growth, yield, or fiber quality characteristics of these cotton cultivars.
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Machado, Fábio Ribeiro. "Componentes de rendimento e qualidade de sementes de soja relacionado a aplicação de fertilizantes foliares." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1261.

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A utilização de fertilizantes foliares na cultura da soja tem aumentado nas últimas safras, devido a sua rápida resposta e ao baixo custo de utilização. Porém, na maioria das vezes a aplicação é realizada sem um prévio diagnóstico da lavoura, ou seja, sem critérios técnicos que justifiquem a sua utilização. Visando dar maiores subsídios a técnicos e produtores, o presente trabalho teve por objetivo estudar o efeito da aplicação de diferentes fertilizantes foliares sobre os componentes de rendimento e qualidade da semente de soja. O experimento foi implantado em três locais, em delineamento experimental de blocos casualizados em esquema fatorial 9 x 2, com três repetições por tratamento. O primeiro fator foi constituído pelos tratamentos (T), referentes a aplicação dos diferentes fertilizantes foliares, sendo: T1- Testemunha, T2-Produto A, T3- Produto B; T4- Produto C; T5- Produto D; T6 – Produto E; T7- Produto F, T8- Produto G e T9- Produto H. O segundo fator foi formado pelas duas épocas de aplicação dos produtos, uma em R2 (pleno florescimento) e a outra em R5 (enchimento de grão). O experimento foi dividido em dois estudos. No estudo um, verificou-se o efeito da aplicação de diferentes adubos foliares sobre os componentes de rendimento e produtividade da soja, onde foram avaliadas as variáveis, teor de nutriente foliar, índice de clorofila, teor de proteína, teor de óleo no grão, altura de plantas e os componentes de rendimento: número de vagens por planta, número de grãos por vagem, número de grãos por planta, massa de 1000 sementes e produtividade. Também foi realizada a análise econômica, para verificar os benefícios econômicos do uso desta tecnologia. No estudo dois, avaliou-se o desempenho das sementes de soja em função da aplicação dos produtos comerciais e épocas de aplicação em apenas dois locais. Neste, foram avaliadas as variáveis: percentagem de germinação; emergência em campo; índice de velocidade de emergência; comprimento de parte aérea; comprimento de raiz; matéria seca de plântulas. Apesar de ter ocorrido incremento nos teores foliares de alguns nutrientes devido à aplicação dos produtos, não foram observados resultados positivos no aumento da produtividade, possivelmente, porque os teores dos nutrientes no solo e a adubação de plantio foram suficientes para atender as exigências da cultura. Da mesma forma, a utilização dos fertilizantes foliares nas épocas de aplicação estudadas não influenciaram a qualidade fisiológica das sementes de soja.
Abstract The use of foliar fertilizers on soybean has increased in the last crops, thanks to your fast answer and low cost of use. However, the application usually is carried without a prior diagnosis of tillage, in other words, without technical criteria that justify your use. In order to give more subsidies to technicians and producers the present study aimed to study the effect of different foliar fertilizers about the yield components and soybean seed quality. The experiment was deployed in three locations, in experimental delimitation of randomized block in factorial plan 9 x2, with three replicates per treatment. The first factor relates to the treatment (T) regarding the application of different foliar fertilizers are: T1-Attestant, T2-Product A, T3- Product B; T4- Product C; T5- Product D; T6 – Product E; T7- Product F, T8- Product G e T9- Product H. The second factor refers to the two times of application of the product, one in R2 (full bloom) and the other in R5 (grain filling). The experiment was divided into two studies. In the first study, it was found the effect of foliar application of different manures on yield components and soybean yield, where the variables were evaluated, foliar nutrient content, chlorophyll content, protein content, oil content in the grain, plant height and yield components: number of pods per plant, number of grains per pod, number of grains per plant, mass of 1000 seeds and productivity. Also in this study was realized the economic analysis to verify the economic benefits the use of this technology. In study 2, was verified the performance of soybean seeds in function of application to the commercial products and application times in only 2 locations. These variables were analyzed: germination percentage; emergence in the field; speed index emergency; length of the shoot; root length; dry matter of seedlings. Although there was an increase in foliar levels of some nutrients due to products application, it was observed that had no positive results in increased productivity, possibly because the levels of nutrients in the soil and the planting fertilization were sufficient to meet crop requirements. Furthermore, the use of foliar fertilizers in the studied application times did not affect the physiological quality of soybean seeds.
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Nogueira, Lais Meneghini. "Doses e modos de aplicação de Boro e adubação com Zinco na cultura do milho /." Ilha Solteira, 2016. http://hdl.handle.net/11449/138268.

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Abstract:
Orientador: Marcelo Carvalho Minhoto Teixeira Filho
Resumo: As deficiências de boro (B) e zinco (Zn) comumente ocorrem em solos de Cerrado. Por isso, para obtenção de maiores produtividades de milho é necessário entender melhor a interação desses elementos, como se existe efeito sinérgico ou antagônico na absorção destes micronutrientes do solo, tal como o modo de aplicação mais vantajoso (via solo ou foliar) e o efeito residual destas adubações. Sendo assim, objetivou-se avaliar o efeito de doses de B aplicadas via solo e via foliar, ambos com ou sem adubação com Zn no solo sobre o estado nutricional, componentes de produção e produtividade do milho primavera/verão e o residual destas adubações via solo no milho outonal, em solo de Cerrado com baixo teor de boro. O experimento foi desenvolvido em um Latossolo Vermelho distrófico em sistema plantio direto. O delineamento experimental dos dois experimentos foi em blocos ao acaso com quatro repetições, dispostos em esquema fatorial 2 x 5, sendo: com ou sem adubação via solo com 2 kg ha-1 de Zn, na forma de sulfato de zinco aplicados na ocasião da semeadura do milho primavera/verão; e 5 doses de B (0, 1, 2, 3 e 4 kg ha-1 na semeadura do milho primavera/verão (experimento 1) ou 0, 170, 340, 510 e 680 g ha-1, que correspondem respectivamente, 0; 0,25; 0,50; 0,75 e 1% de ácido bórico na calda de pulverização aplicada via foliar na fase de pré-pendoamento do milho (experimento II). Após a colheita do milho primavera/verão, avaliou-se o residual destes tratamentos aplicados via solo no cultiv... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Boron deficiencies (B) and zinc (Zn) commonly occur in Cerrado soils. Thus, for obtaining higher maize yields is necessary to better understand the interaction of these elements, as if exists synergistic or antagonistic effect on the absorption of these micronutrients in soil, such as the most advantageous mode of application (by soil or foliar) and the effect of these residual fertilizations. Therefore, it was aimed to evaluate the effect of B rates applied to soil (experiment I) and foliar application (experiment II), both with or without Zn fertilization in the soil on nutritional status, yield components and grains yield of spring/summer maize and the residual of these fertilizations in the soil in the autumnal maize, in Cerrado soil with low boron content. The experiment was conducted in an Oxisol under notillage system. The experimental design of the two experiments was a randomized block with four replications, in a factorial 2 x 5, being: with or without soil fertilization with 2 kg ha-1 Zn, in the form of zinc sulfate applied on the occasion of sowing of spring/summer maize; and 5 doses of B (0, 1, 2, 3 and 4 kg ha-1 applied at sowing of spring/summer maize (experiment 1) or 0, 170, 340, 510 and 680 g ha-1 , which correspond respectively, 0, 0.25, 0.50, 0.75 and 1% of boric acid in the spray solution applied by foliar in pre-tasseling of maize (experiment II)). After harvesting of the spring/summer maize was evaluated the residual of these treatments applied to the s... (Complete abstract click electronic access below)
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48

Fenólio, Luiz Gonzaga. "Efeito de diferentes águas e fertilizantes foliares em caldas acaricidas no controle do ácaro Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae) em citros /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/91371.

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Abstract:
Orientador: Marcelo da Costa Ferreira
Banca: Carlos Amadeu Leite de Oliveira
Banca: José Roberto Scarpellini
Resumo: O ácaro Brevipalpus phoenicis é considerado uma das principais pragas dos citros, por ser vetor do CiLV "Citrus Leprosis Virus", agente causal da doença leprose do citros, uma das doenças de maior importância na citricultura brasileira. Objetivou-se avaliar a influência de alguns parâmetros qualitativos da água, no controle químico com os acaricidas cyhexatin, propargite e acrinathrin, adicionando-se ainda diferentes sais nutricionais na forma dos fertilizantes foliares cloreto de zinco, cloreto de manganês, fosfito de potássio, sulfato de magnésio e uréia nas respectivas misturas, aplicando-se sobre o ácaro B. phoenicis. Na primeira parte do trabalho, foi utilizada água do açude principal do Câmpus de Jaboticabal-SP, tendo sido realizados três experimentos, com 9 tratamentos e 4 repetições cada um, de ação indireta das caldas sobre o acarino, no Laboratório de Acarologia do Departamento de Fitossanidade da UNESP, Câmpus de Jaboticabal-SP. Na segunda parte do trabalho, utilizou-se águas dos municípios paulistas de Pirassununga, Pirangi e Itápolis, foram realizados dois experimentos, com 27 tratamentos e 4 repetições cada um. As águas utilizadas nos experimentos, foram analisadas isoladamente e após as diferentes misturas, o pH, a condutividade elétrica, a temperatura e o oxigênio dissolvido. Nas duas partes do trabalho, cada fruto de laranja foi considerado uma repetição. Os frutos utilizados mo primeiro trabalho, não receberam qualquer tratamento com produto fitossanitário nos 6 meses que antecederam o experimento, e, os frutos utilizados no segundo trabalho, não receberam qualquer tratamento fitossanitário nos 13 meses que antecederam o experimento. As doses dos produtos utilizados nos tratamentos, foram expressos em mL de produto comercial por 100 L de água: cyhexatin a 50 mL; propargite a 100 mL; acrinathrin a 10 mL conforme recomendação... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The mite Brevipalpus phoenicis is considered a major pest of citrus because it is vector CiLV "Citrus Virus Lepers, causal agent of citrus leprous, one of the most important diseases in citrus Brazil. Purpose to evaluate the influence some qualitative parameters of water, chemical control with acaricides cyhexatin, propargite and acrinathrin, adding yet different nutrient salts in the form of leaf fertilizer zinc chloride, manganese chloride, potassium phosphite, magnesium sulfate and urea in their mixtures, applying on the mite B. phoenicis. The first part of the work used in the pond water Main Campus of Jaboticabal, having performed three experiments with 9 treatments and 4 replicates each, direct action on the tails of the mite in the Laboratory of Acarology the Fitossanidade Department of UNESP, Jaboticabal-SP. The second part of this work, we used the waters of the counties of Pirassununga, Pirangi and Itápolis, two experiments were conducted with 27 treatments and 4 replicates um. As waters used in experiments were analyzed separately and after the different mixtures, pH, electrical conductivity, temperature and oxygen dissolved. The two pieces of work, each orange fruit was considered a fruit used repetition. The first work, received no treatment with plant protection product in the 6 months prior to the experiment, and fruit used in the second study, received no treatment plant in the 13 months preceding the trial. The doses of products used in treatments were expressed as ml of commercial product per 100 L of water: cyhexatin to 50 mL; propargite to 100 mL, 10 mL acrinathrin as recommended by the manufacturer and a control without aplication. The second part of the work has not used the product cyhexatin because information from the manufacturer that the same would no longer be marketed in Brasil. Orange used with symptoms of the disease... (Complete abstract click electronic access below)
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49

Zuim, Carlos Eduardo [UNESP]. "Efeito de adubação orgânica e mineral e culturas de entressafra na cultura da soja (Glycine max (L) Merrill) no sistema plantio direto." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/98880.

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Abstract:
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Universidade Estadual Paulista (UNESP)
A busca pela qualidade do solo como base de sustentação do sistema de produção, tem aumentado o desafio de compreender um sistema que, além de reduzir sensivelmente a degradação do meio ambiente, pode permitir maior retorno econômico ao agricultor. Nesse sentido o presente trabalho foi desenvolvido no período de abril de 2005 a abril de 2006, com o objetivo de avaliar na cultura da soja, no sistema de plantio direto, o efeito de diferentes culturas de cobertura e presença ou ausência de adubação orgânica e mineral. O trabalho foi desenvolvido no município de Guararapes-SP (50°39’W, 21°09’S e 412 m de altitude aproximadamente) em um Latossolo Vermelho amarelo, com textura média, sendo cultivado com culturas anuais a partir de 1993. O delineamento experimental utilizado foi o em blocos casualizados com 4 repetições, com os tratamentos dispostos em um esquema fatorial 5x2x2, ou seja, 5 culturas de cobertura (milho, milheto, sorgo, braquiária e mamona), cultivadas no período de outono/inverno, na presença e ausência de adubação orgânica (11.512 kg/ha de esterco de galinha), sendo semeado em sucessão, a cultura da soja, cultivar MGBR 46 (Conquista), na presença ou ausência de adubação mineral (500 kg/ha da fórmula 02-20-15). As culturas de cobertura e a soja foram irrigadas pelo sistema pivô central. As avaliações constaram da produção de massa seca das culturas de cobertura, estado nutricional da soja no florescimento pleno, características agronômicas e produção de grãos da soja e características químicas do solo, em diferentes profundidades, após o cultivo da soja. Através dos resultados obtidos, verificou-se que o milho apresentou maior produção de massa seca como cultura de cobertura, mas todas as...
The search for the soil quality as sustentation base of production system, has stimulated the challenge to understand a system that, beyond sensibly reducing the environment degradation, may allows greater economic return to the farmer. Thus, the present work was developed in the period of April 2005 to April 2006, with the objective to evaluate in soybean crop, in no tillage system, the effect of different cover crops and presence or absence of organic and mineral fertilization. The work was developed at the municipal district of Guararapes, State of São Paulo (50°39' W, 21°09' S and 412 m altitude approximately) in a Typic Haplustox, with sandy texture, being cultivated with annual crops since 1993. The exeprimental design used was randomized blocks with four replications, with treatments disposed in a 5x2x2 factorial scheme, i.e., five cover crops (corn, millet, sorghum, braquiaria grass and castor bean), cultivated in the autumn/winter period, in presence and absence of organic fertilization (11,512 kg ha-1 of chicken manure fertilizer), being sowedin succession of soybean crop, MGBR 46 cultivar, in presence or absence of mineral fertilization (500 kg ha-1 of 02-20-15 formula). The cover cultures and soybean had been irrigated by center pivot irrigation systems.The evaluations was cover crops dry matter production, nutritional status in flowering, agronomic characteristics and soybean grain production, soil chemical characteristis, in different depths, after soybean. Through the obtained results, it verified that the corn presents greater dry matter production as cover crop, but all the evaluated cover crops are adjusted to precede soybean; organic fertilization increases cover crop dry matter production, beyond provided significant P, Ca and K increases in 0 to 0.05 and 0.05 to 0.10 m depth and P and K in 0.10 to 0.20 m depth; ...(Complete abstract click electronic access below)
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50

Fenólio, Luiz Gonzaga [UNESP]. "Efeito de diferentes águas e fertilizantes foliares em caldas acaricidas no controle do ácaro Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae) em citros." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/91371.

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Abstract:
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O ácaro Brevipalpus phoenicis é considerado uma das principais pragas dos citros, por ser vetor do CiLV “Citrus Leprosis Virus”, agente causal da doença leprose do citros, uma das doenças de maior importância na citricultura brasileira. Objetivou-se avaliar a influência de alguns parâmetros qualitativos da água, no controle químico com os acaricidas cyhexatin, propargite e acrinathrin, adicionando-se ainda diferentes sais nutricionais na forma dos fertilizantes foliares cloreto de zinco, cloreto de manganês, fosfito de potássio, sulfato de magnésio e uréia nas respectivas misturas, aplicando-se sobre o ácaro B. phoenicis. Na primeira parte do trabalho, foi utilizada água do açude principal do Câmpus de Jaboticabal-SP, tendo sido realizados três experimentos, com 9 tratamentos e 4 repetições cada um, de ação indireta das caldas sobre o acarino, no Laboratório de Acarologia do Departamento de Fitossanidade da UNESP, Câmpus de Jaboticabal-SP. Na segunda parte do trabalho, utilizou-se águas dos municípios paulistas de Pirassununga, Pirangi e Itápolis, foram realizados dois experimentos, com 27 tratamentos e 4 repetições cada um. As águas utilizadas nos experimentos, foram analisadas isoladamente e após as diferentes misturas, o pH, a condutividade elétrica, a temperatura e o oxigênio dissolvido. Nas duas partes do trabalho, cada fruto de laranja foi considerado uma repetição. Os frutos utilizados mo primeiro trabalho, não receberam qualquer tratamento com produto fitossanitário nos 6 meses que antecederam o experimento, e, os frutos utilizados no segundo trabalho, não receberam qualquer tratamento fitossanitário nos 13 meses que antecederam o experimento. As doses dos produtos utilizados nos tratamentos, foram expressos em mL de produto comercial por 100 L de água: cyhexatin a 50 mL; propargite a 100 mL; acrinathrin a 10 mL conforme recomendação...
The mite Brevipalpus phoenicis is considered a major pest of citrus because it is vector CiLV Citrus Virus Lepers, causal agent of citrus leprous, one of the most important diseases in citrus Brazil. Purpose to evaluate the influence some qualitative parameters of water, chemical control with acaricides cyhexatin, propargite and acrinathrin, adding yet different nutrient salts in the form of leaf fertilizer zinc chloride, manganese chloride, potassium phosphite, magnesium sulfate and urea in their mixtures, applying on the mite B. phoenicis. The first part of the work used in the pond water Main Campus of Jaboticabal, having performed three experiments with 9 treatments and 4 replicates each, direct action on the tails of the mite in the Laboratory of Acarology the Fitossanidade Department of UNESP, Jaboticabal-SP. The second part of this work, we used the waters of the counties of Pirassununga, Pirangi and Itápolis, two experiments were conducted with 27 treatments and 4 replicates um. As waters used in experiments were analyzed separately and after the different mixtures, pH, electrical conductivity, temperature and oxygen dissolved. The two pieces of work, each orange fruit was considered a fruit used repetition. The first work, received no treatment with plant protection product in the 6 months prior to the experiment, and fruit used in the second study, received no treatment plant in the 13 months preceding the trial. The doses of products used in treatments were expressed as ml of commercial product per 100 L of water: cyhexatin to 50 mL; propargite to 100 mL, 10 mL acrinathrin as recommended by the manufacturer and a control without aplication. The second part of the work has not used the product cyhexatin because information from the manufacturer that the same would no longer be marketed in Brasil. Orange used with symptoms of the disease... (Complete abstract click electronic access below)
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