Tesis: "Winter crops"

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Steffl, Nicholas James. "Relay-Sowing Soybean Into Established Winter Annual Cover Crops." Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/31714.

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Cover crop acreage continues to increase as soil, grazing, and ecosystem benefits become better known. The profit aspect of sustainability could be improved by producing intersown cover crops with an added commodity value. Objectives of this research were to determine if field pennycress, winter camelina, and winter rye could act as effective, feasible, intersown cover crops in soybean-soybean-corn, and, corn-soybean-corn crop sequences. Three sowing dates of each crop were established the previous fall, and soybean, relay-sown the following spring at Prosper and Casselton, ND. Experimental design was a 10 treatment, four replicate, randomized complete block with a 3×3 factorial arrangement, and one non-treated check (NTC) within each replicate. In both crop sequences, treatments containing field pennycress and winter camelina had either similar, or reduced soybean seed yield in relation to the (NTC). Additional yield obtained from field pennycress and/or winter camelina seed did not render this cropping system economically feasible.

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Hui, Wun-fung, and 許桓峰. "Bird damage to vegetable crops in Long Valley during winter." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/194581.

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Long Valley is the largest agricultural wetland in Hong Kong and supports a high level of biodiversity. The implementation of Management Agreement project in Long Valley has successfully enhanced its conservation value through habitat management and various eco-agricultural practices. However, the conflict between profitable agricultural yield and bird conservation in the area has also been intensifying as reflected by the increasing number of complaints of bird-related crop damage from local farmers in winter. The study aimed to assess the extent and impact of crop damage caused by birds in Long Valley during winter. The first part of the study involved a transect survey in the area reported to be the most severely affected area of Long Valley to determine the bird diversity and abundance, also the environmental factors of individual farmland plots were collected for analysis of their relationship with bird distribution. The bird species responsible for crop damage (targeted species) were also identified. The second part of the study evaluated the impact of different targeted species by using the technique of focal animal sampling, which involved focused observation of individual bird’s behaviour in the field and to quantify its time budget spent on crop-damaging behaviour. In order to understand the perspectives from farmers, face-to-face interviews with farmers practicing in the area were also conducted. The study identified five species to have crop-damaging behaviour, which can be further divided into two groups: the crop-consuming species causing actual crop damage included Chinese Bulbul (Pycnonotus sinensis), Crested Myna (Acridotheres cristatellus) and Eurasian Tree Sparrow(Passer montanus). The incidental crop-pecking species causing minimal crop damage included the White Wagtail (Motacilla alba)and Yellow Wagtail (Motacilla tschutschensis). Lettuce (Lactuca sativa) was the only type of crop suffering from bird damage. The intensity of crop-damaging behaviour of a species was estimated by the mean time allocated in crop consumption, and was found to be 66.7%±7.3% in Chinese Bulbul, 31.6%±29.1% in Eurasian Tree Sparrow and 8.9%±12.0% in Crested Myna. However, taking into account of the abundance, distribution and activity record of a species, Crested Myna showed the greatest overall impact to the vegetable crops. Chinese Bulbul showed a relatively focal but intensive damage to a few plots. It was found that having wires and a wet field nearby the plots were significant determinants of the presence of Eurasian Tree Sparrow. And the presence of Chinese Bulbul was significantly associated with the use of bird deterrents. Crested Myna was found in significantly higher numbers in late afternoon and was associated with plots having the seedling stage of lettuce growth. The study shows that birds do cause localized and patchy damage to vegetable crops in Long Valley. Individual farmlands may exhibit variations in severity of the damage due to the difference in species distribution and environmental factors. The management of bird damage must therefore be individualized from plot to plot. Also education and engagement with local farmers are indispensable to maintaining sustainable agricultural development while conserving avifauna in Long Valley. published_or_final_version Environmental Management Master Master of Science in Environmental Management

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Higgins, Todd R. "An economic analysis of the value of grazing winter cover crops." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/36221.

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Master of Agribusiness Department of Agricultural Economics Jason S. Bergtold Cover crops can be used as forage for cattle and other grazing animals. This research investigated the net returns of using cover crops for forage or grazing under four scenarios. These scenarios were: 1) a mixed crop and livestock producer who owns a herd of cattle and has both dry or pregnant cows and weaned calves available to graze corn stover and cover crops; 2) a crop farmer who purchases stocker cattle for the purpose of grazing the cover crop and corn stover; 3) a crop farmer who leases out a corn stover and cover crop field to a livestock producer (and who provides value-added services to the livestock producer for a fee); and 4) an integrated operation with crops and cattle where cover crops are not grown and hay is fed to cattle during the winter months. Each of these scenarios had different budgets, risks, and profit potentials. The research aimed to address the risks and profit potentials for each scenario. The stocking density was initially set at three cows and 31 steers for a period of 90 days, and alternatively, three cows and 25 steers for a period of 120 days. Two sets of cattle pricing data were used: the average historical prices from 1992 to 2011 and reported prices from a regional stockyard for the period of November 2016 to March 2017. The results showed that the initial stocking densities used for scenarios one and two were too low to provide profitable net returns regardless of pricing data used. Net returns for scenario three were also not profitable based on the services rendered and the management fee charged. Scenario four was profitable on one occasion. November steers with a 500 lb. average starting weight fed hay and concentrate for 120 days resulted in a positive net return of $375. A second analysis was done using stocking rates of 50, 75, or 100 steers to determine if increasing stocking density would result in a positive net return using only the 2016/2017 pricing data and only evaluating net returns on 2.0 and 2.5 lbs. of average daily gain. Positive net returns were achieved at various start weights and average daily gain rates at stocking rates of 75 and 100 animals. No positive net returns were realized at the stocking rate of 50 animals/100 acre field. The management fee charged for providing management services under scenario three was adjusted based on stocking densities to determine if a positive net return could be achieved at the set fee rate of $0.875/head/day. At that rate, no stocking rate resulted in a positive net return. Using the cost data, less the $900 field lease income, a breakeven pricing point for the management fee was determined for each stocking density and grazing duration within the scenario. Management of cost factors to achieve greater chances of profitability and additional research needs are discussed.

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Freeman, Oliver W. II. "Winter cover crops in corn and forage sorghum rotations in the Great Plains." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17892.

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Doctor of Philosophy Department of Agronomy Mary Beth Kirkham In Kansas, winter cover crops have a new interest with the development of summer crops for biofuel. When a crop is harvested for bioenergy, the residue is removed leaving the soil prone to erosion during the winter. It is possible that the use of winter cover crops may allow for more residue to remain in a field while keeping the soil from blowing. Therefore, the objective of this research was to determine the effect of two winter cover crops on the growth of two biofuel crops, corn (Zea mays L.) and forage sorghum [Sorghum bicolor (L.) Moench] in a corn-forage sorghum rotation. The two cover crops were a legume, Austrian winter pea (Pisum sativum var. arvense Poir.) and winter wheat (Triticum aestivum L.). Control plots were fallowed. The experiment was done for two years (2010 and 2011) at two locations: under rain-fed conditions in Manhattan in the northeastern part of Kansas, where the soil was a Belvue silt loam (coarse-silty, mixed superactive non-acid, mesic Typic Udifluvents) and under irrigated conditions in Tribune in the western part of Kansas, where the soil was a Richfield silt loam (fine, smectitic, mesic Aridic Argiustolls). Two levels of nitrogen were added to the soil: 0 and 101 kg ha[superscript]-1 N. Grain and stover yields of the corn and forage sorghum were determined at harvest of the crops in the fall, and dry matter production of the cover crops was determined at their termination in the springs of 2011 and 2012. Additional nitrogen fertilizer increased grain and stover yields in both growing seasons at both locations, except for Manhattan in 2010. During the second winter of the study, Austrian winter pea did not emerge in Manhattan, probably due to a combination of cold temperatures and drought. Austrian winter pea survived both winters at Tribune. Corn yielded more grain than did the forage sorghum in Manhattan in 2011 and in Tribune in 2011. This suggests that, under both rain-fed and irrigated conditions in Kansas, corn would potentially be more productive for bioenergy production than forage sorghum. The results of the study also showed that winter wheat for both Manhattan, Kansas, and Tribune, Kansas, should be the cover crop chosen, because of its ability to grow well during the off-season of the bioenergy crops and to provide soil cover during winter.

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Geiszler, Melissa Marie. "Interseeding Cereal Rye and Winter Camelina into Corn in North Dakota." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29214.

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Limited photosynthetically active radiation (PAR) can reduce interseeded cover crop growth in corn (Zea mays L.). Two experiments in North Dakota evaluated the effect that hybrid relative maturity (RM), row width, and cover crop planting date have on cereal rye (Secale cereale L.) and winter camelina [Camelina sativa (L.) Crantz.] establishment when interseeded into 80 and 89 RM hybrids at V7 and R4 growth stages in 56- and 76 cm corn row widths. Cover crop biomass was typically less than 100 kg ha-1. In the following spring larger amounts of PAR beneath the 80 RM hybrid increased cover crop biomass by 20.8 kg ha-1. Cover crop biomass tended to be greater in the 76 cm row width but was not significantly different from the 56 cm width. Cover crops decreased residual soil nitrate by 6.0 kg ha-1 in the fall and by 15.6 kg ha-1 in the spring.

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Vaughan, Jeffrey David. "Management and assessment of winter cover crop systems for supplying nitrogen to corn in the mid-Atlantic region of the United States." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07212009-040446/.

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7

McDonald, Paul Bryant. "Management of self-seeding winter cereal cover crops in a soybean-corn rotation." [Ames, Iowa : Iowa State University], 2007.

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8

Daniel, James B. II. "Using Winter Annual Cover Crops in a Virginia No-till Cotton Production System." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/35681.

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Cotton (Gossypium hirsutum L.) is a low residue crop, that may not provide sufficient surface residue to reduce erosion and protect the soil. A winter annual cover crop could alleviate erosion between cotton crops. Field experiments were conducted to evaluate selected winter annual cover crops for biomass production, ground cover, and N assimilation. The cover crop treatments were monitored under no-till and conventional tillage systems for the effects on soil moisture, cotton yield and quality. Six cover crop treatments, crimson clover (Trifolium incarnatum L.), hairy vetch (Vicia vilosa L.), hairy vetch and rye (Secale cereale L.), rye, wheat (Triticum aestivum L. amend. Thell.), and white lupin (Lupinus albus L.), and two tillage systems (conventional and no-till) were arranged in a split-plot design with four replications. Cover crop biomass production depended on climate conditions. Ground cover percent and N assimilation by cover crops were directly correlated with the amount of biomass produced within cover crop treatments. Within a range of near average winter temperatures, all cover crops except lupin provided enough ground cover to comply with federal conservation tillage standards. More ground cover remained on the soil surface further into the cotton growing season following the small grain treatments compared to the legume cover crop treatments. Soil moisture was higher (P < 0.05) under no-till compared to conventional tillage during the periods of drought in 1997. Tillage system had no effect on cotton yield and quality in 1995 and 1996. High cover crop biomass production coupled with an extended cotton growing season in 1995 resulted in higher lint yield for cotton grown following the hairy vetch + rye treatment compared with cotton grown following the wheat treatment. High heat unit accumulation in October 1995 led to the over maturity of cotton fiber and high micronaire values for cotton grown following all cover crop treatments. The high micronaire values (5.0 - 5.2) for cotton grown in all cover crop treatments except hairy vetch + rye (4.9), resulted in a market price deduction of 1.4 cents per kilogram of lint in 1995. All cover crops used in this experiment, with the exception of lupin, provided enough ground cover within a range of average winter temperatures to meet federal conservation requirements. The winter annual cover crops in a no-till cotton production system provided greater soil moisture conservation during periods of drought, and produced cotton yields and quality comparable to conventional tillage. Master of Science

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9

Buteler, Micaela. "Integrated management of the Wheat Stem Sawfly by exploiting semiochemicals to enhance trap crops." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/buteler/ButelerM0508.pdf.

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The wheat stem sawfly, Cephus cinctus Norton (WSS) causes significant damage in cereal crops in the northern Great Plains of North America. Recently, the use of winter wheat as a trap crop to protect spring wheat from this insect pest in a wheat-fallow cropping system was evaluated, yielding promising results. Subsequently, the overall objective of this dissertation research was to improve the efficacy of winter wheat trap crops to manage the WSS. Oviposition behavior studies in the presence of hosts infested by conspecifics showed that WSS did not avoid infested hosts. These results confirmed the potential of a trap to provide a sink for multiple eggs, resulting in increased WSS mortality due to cannibalism. I identified suitable winter wheat cultivars based on agronomic characteristics that influence WSS behavior in conjunction with the emission of behaviorally active plant volatiles, as well as the performance of the cultivars in the area where the pest occurs. Results from this study identified five cultivars, Norstar, Morgan, BigSky, Neeley, and Rampart, with good potential as trap crops. Norstar emitted greater amounts of attractive volatile compound ÃŸ-ocimene, and was the preferred host in greenhouse choice tests. Based on these results, a perimeter trap cropping trial comparing three winter cultivars as traps (Norstar, Neeley and Rampart) to protect spring wheat was conducted for two consecutive years. Two spring wheat cultivars differing in suitability for infestation by sawflies were chosen as the main crop. WSS abundance was significantly greater in the winter wheat traps than in the adjacent unattractive spring cultivar Conan both years of the experiment and greater than an attractive spring cultivar Reeder in 2005. No differences in infestation were observed between winter cultivars, although greater numbers of eggs were found in Norstar than in Rampart traps. Swathing the trap crop before grain fill killed most larvae developing in the trap crop. Finally, I investigated the effect of a synthetic attractive compound, (Z)-3-hexenylacetate, on oviposition and found that application of this compound in a lanolin paste resulted in increased oviposition by females in greenhouse choice tests. The results obtained suggest that a trap cropping management strategy involving attractive and unattractive cultivars, and semiochemically assisted trap cropping by application of synthetic host volatiles, show potential to manage the WSS.

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Mupambwa, Hupenyu Allan. "Winter rotational cover crops effects on soil strength, aggregate stability and water conservation of a hardsetting cambisol in Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/453.

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Winter rotational cover crops (WRCC) are often used to boost soil fertility and plant nutrition. However, selection and use of WRCC for soil physical improvement is usually overlooked. The objective of this study was to determine the effects of WRCC on soil strength, aggregate stability and water conservation of a hardsetting soil. The soil physical properties were determined after four rotations of growing monocultures of vetch (Vicia dasycarpa cv. Max), lupin (Lupinus angustifolius cv. Tanjil) and oats (Avena sativa cv. Sederberg) and after two rotations of growing bicultures of oats (Avena sativa cv. Pallinup) and vetch (Vicia dasycarpa cv. Max) across two soil layers, 0 to 15 cm and 15 to 30 cm. The individual WRCC and a weedy fallow constituted the treatments in the monoculture study whilst in the biculture study the various combinations of WRCC namely; 90% oat plus 10% vetch (O90V10); 70% oat plus 30% vetch (O70V30) and 50% oat plus 50% vetch (O50V50) and a weedy fallow constituted the treatments. After four rotations with cover crop monocultures, oats significantly (P ≤ 0.05) reduced penetration resistance (PR) whilst vetch increased PR in both soil layers compared to the weedy fallow control. The effect of the biculture treatments was only experienced within the 15 to 30 cm depth. The treatments O50V50 and O70V30 increased the PR compared to the control. The WRCC in monoculture significantly increased the soil aggregate stability relative to the control in both soil layers. Vetch, lupin and oats resulted in a 41.7%; 20.4% and 15.7% increase in MWD in the 0 to 15 cm soil layer and 47.2%; 44.2% and 39.7% in the 15 to 30 cm depth, respectively. An increase in aggregate stability was associated with increased macro-aggregation. Under the biculture, WRCC slightly increased, non- significantly, the aggregate stability. Both hot water and dilute acid extractable polysaccharides showed no significant correlation with aggregate stability in the two studies. Oats monoculture resulted in a significant difference (P ≤ 0.05) on cumulative infiltration compared to the control. However, after 2 h vetch and lupin showed no significant difference from the control on cumulative infiltration. Oats resulted in a 7.8% increase in final infiltration rate (FIR) whilst vetch and lupin reduced FIR by 9% and 16.7% respectively, compared to the control. Bicultures of oats and vetch significantly (P ≤ 0.05) increased cumulative infiltration compared to the weedy fallow control. A similar significant increase in FIR was also observed under bicultures. The treatments O50V50; O90V10 and O70V30 resulted in a 163.3%; 113.3% and 105.4% increase in FIR respectively, compared to the control. Cover crop monocultures significantly (P ≤ 0.05) increased plant available water (PAW) compared to the weedy fallow, with vetch, oats and lupin resulting in a 28.3%; 22% and 23.9% increase respectively, in PAW. However, no significant differences were observed on PAW after two rotations with bicultures. Compared with winter weedy fallow, WRCC improved most of the soil physical properties under study, with the most suitable results expected under bicultures compared to monocultures. Under CA, selection of WRCC like oats, vetch and lupin, one should therefore take into consideration their effects on soil physical properties as a selection criterion and not biomass and fertility alone.

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Cooper, Jeannie. "Modelling barley disease epidemics for use with decision support systems." Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312358.

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In a field trial during 1995/96, epidemics of Pyrenophora teres and Rhynchosporium secalis were studied in winter barley with concurrent records of weather data to identify key environmental parameters that affect epidemics. Temperature was identified as a key influence in the onset of P. teres epidemics. Disease symptoms were observed to progress when daytime temperatures consistently reached 10°C and minimum nightime temperatures for the same period remained above 5°C. Short leaf wetness periods and longer photoperiods also correlated with increased disease levels during the P. teres epidemic. In R. secalis, relationships between disease onset and individual environmental parameters were not consistent, however, high rainfall events and prolonged leaf wetness periods were recorded prior to greatest disease increase. Hypotheses based on individual and combined weather criteria, based on the results of the 1995/96 field trials, were tested in controlled conditions. The effect of temperature on P. teres was confirmed, with small differences between ascospores and conidiospores. Latent period of both P. teres and R. secalis was influenced by cultivar resistance, inoculum concentration and plant growth stage. In a second field trial in 1996/97 reduced dose fungicide programmes, using hypotheses of epidemic development based on environmental criteria, were tested and compared favourably to a standard programme with greater fungicide doses. Environmental criteria were combined within a decision model for timed reduced-dose fungicide programmes for each pathogen, where risk scores were allotted for each set of criteria and fungicide treatment decision was based on the cumulative risk score. Both the P. teres and R. secalis decision models were tested in a final field trial in 1997/98. Lower disease levels and greater yield response, with lower fungicide input, was achieved from both models compared to a standard fungicide programme. The potential for using the P. teres and R. secalis decision models in a decision support system for cereals is discussed.

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12

Brown, Alston Neal. "Factors affecting the nutritional composition and digestibility of corn for silage: Cover crops and cell wall composition." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/78909.

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Corn silage is one of the major components in dairy cattle rations in the United States. Many factors affect the nutritional composition of corn for silage, such as cropping system, including cover crops, and the composition of the corn plant cell wall. The objectives of the first study were to determine the nutritional quality of different winter crops for silage and to determine the impact of the various winter crops on the succeeding productivity of corn and sorghum. Experimental plots were planted with 15 different winter crop treatments: 5 winter annual grasses in monoculture or with one of two winter annual legumes (crimson clover [CC] and hairy vetch [HV]). After harvesting the winter crops, each plot was planted with either corn or forage sorghum. Crimson clover increased DM yield compared to monocultures but HV did not. Adding legumes increased the crude protein concentration, but reduced the fiber and sugar concentrations of the forages. Even though in vitro neutral detergent fiber digestibility was reduced with the addition of legumes, the concentration of highly digestible non-fibrous components is greater in the mixtures than the monocultures, increasing the nutritive value of the silage. The objective of the second study was to determine the cell wall (CW) composition along the corn stalk. Three phytomers of corn plants were examined: center (C) of ear insertion, upper (U) and lower (L) phytomers. Each phytomer was cut into 4 sections: top (T), middle (M), bottom (B), and node (N). The CW, uronic acid (UA), glucose (GLU), and lignin concentrations did not change among phytomers. The concentrations of arabinose (ARA) and xylose (XYL) were greater in the U than in the L phytomers. Concentrations of CW, ARA, and XYL increased from B to T within the phytomer, but UA and GLU concentrations decreased from B to T. Lignin did not change within the phytomer. In mature corn for silage, changes within the corn internode may be more useful in determining how the environment changes the CW. Ph. D.

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13

Zuck, Peter Christopher. "Evaluation of alternative crops for management of Pratylenchus neglectus in Montana winter wheat production." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/zuck/ZuckP0510.pdf.

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A series of crop rotations were evaluated for their impacts on soil-borne populations of root lesion nematodes, Pratylenchus neglectus. Population changes, measured as the ratio of P. neglectus adults counted at harvest to those counted at planting time, was recorded under a series of two-year rotations alternating winter wheat with either fallow, barley, pea, lentil, canola, and camelina. Fallow, barley, pea, and camelina were found to have a neutral effect on nematode populations (p < 0.001). Winter wheat and canola caused significant increases in populations, while lentils caused significant decreases (p < 0.001). Populations were sustained through winter following winter wheat and barley, but not canola, camelina, pea, lentil, or fallow treatments (p < 0.001). In addition to the rotation study, cultivars of barley and canola were evaluated for their resistance to P. neglectus. Greenhouse trials for barley showed significant differences among 19 cultivars tested (p < 0.001), with a 5-fold difference in P. neglectus multiplication separating the least- from the most resistant. Separation among cultivars was not found with canola (p = 0.20). The information gathered in this study will help Montana wheat growers better understand the impacts of their crop selections on this important pest.

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14

Parker, Steven Roy. "Studies on some factors influencing the reliability of disease measurements in winter wheat crops." Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336955.

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15

Bullard, Amanda Simpson. "Protein Indicators, Quality, and Yield of Winter Durum Wheat Grown in Virginia." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/35457.

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Durum wheat (Triticum durum Desf.) is produced primarily in the Northern Great Plains and the Pacific Southwest of the United States. Current germplasm is predominantly of the spring growth habit. The objective of this study was to determine the feasibility of winter durum production in Virginia based upon both yield and quality parameters. Adaptation and yield potential of available winter durum lines were assessed from 1993-1998, in three physiographic regions in Virginia. The highest average durum yields were produced in the northern piedmont plateau at the Orange County location. Winter durum yields generally averaged 1600-2800 kg/ha less than soft red winter wheat, traditionally grown in the state. The price premium for high quality durum can compensate for this difference in yield. Based on average durum yields, and assuming the grain meets U.S. No. 2 Hard Amber Durum standards, durum production in Virginia would have been more profitable than soft red winter wheat production in 1994 and 1997. Physical and chemical quality analyses of the top 19 performing durum lines were performed to determine grain marketability, suitability for pasta, and potential consumer acceptance of the end product. Protein content and gluten strength of the Virginia grown durum were acceptable. Color, firmness, and cooking loss of pasta produced from Virginia grown durum were comparable to pasta produced from commercial semolina. Requirements for U.S. No. 2 Amber Durum were met by 21% of the lines in both 1996 and 1997. Overall, the wet, humid Virginia climate was the greatest hindrance to durum production and quality. The field trials and quality analyses showed that high quality durum production in Virginia is possible, but not consistent over all years. Master of Science

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Potgieter, Andries B. "Determining broadacre crop area estimates through the use of multi-temporal modis satellite imagery for major Australian winter crops." University of Southern Queensland, Faculty of Engineering and Surveying, 2009. http://eprints.usq.edu.au/archive/00006613/.

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[Abstract]: Since early settlement, agriculture has been one of the main industries contributing to the livelihoods of most rural communities in Australia. The wheat grain industry is Australia’s second largest agricultural export commodity, with an average value of $3.5 billion per annum. Climate variability and change, higher input costs, and world commodity markets have put increased pressure on the sustainability of the grain industry. This has lead to an increasing demand for accurate, objective and near real-time crop production information by industry. To generate such production estimates, it is essential to determine crop area planted at the desired spatial and temporal scales. However, such information at regional scale is currently not available in Australia.The aim of this study was to determine broadacre crop area estimates through the use of multi-temporal satellite imagery for major Australian winter crops. Specifically, the objectives were to: (i) assess the ability of a range of approaches to using multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS) imagery to estimate total end-of-season winter crop area; (ii) determine the discriminative ability of such remote sensing approaches in estimating planted area for wheat, barley and chickpea within a specific cropping season; (iii) develop and evaluate the methodology for determining the predictability of crop area estimates well before harvest; and (iv) validate the ability of multi-temporal MODIS approaches to determine the pre-harvest and end-of-season winter crop area estimates for different seasons and regions.MODIS enhanced vegetation index (EVI) was used as a surrogate measure for crop canopy health and architecture, for two contiguous shires in the Darling Downs region of Queensland, Australia. Multi-temporal approaches comprising principal component analysis (PCA), harmonic analysis of time series (HANTS), multi-date MODIS EVI during the crop growth period (MEVI), and two curve fitting procedures (CF1, CF2) were derived and applied. These approaches were validated against the traditional single-date approach. Early-season crop area estimates were derived through the development and application of a metric, i.e. accumulation of consecutive 16-day EVI values greater than or equal to 500, at different periods before flowering. Using ground truth data, image classification was conducted by applying supervised (maximum likelihood) and unsupervised (K-means) classification algorithms. The percent correctly classified and kappa coefficient statistics from the error matrix were used to assess pixel-scale accuracy, while shire-scale accuracy was determined using the percent error (PE) statistic. A simple linear regression of actual shire-scale data against predicted data was used to assess accuracy across regions and seasons. Actual shire-scale data was acquired from government statistical reports for the period 2000, 2001, 2003 and 2004 for the Darling Downs, and 2005 and 2006 for the entire Queensland cropping region.Results for 2003 and 2004 showed that multi-temporal HANTS, MEVI, CF1, CF2 and PCA methods achieved high overall accuracies ranging from 85% to 97% to discriminate between crops and non-crops. The accuracies for discriminating between specific crops at pixel scale were less, but still moderate, especially for wheat and barley (lowest at 57%). The HANTS approach had the smallest mean absolute percent error of 27% at shire-scale compared to other multi-temporal approaches. For early-season prediction, the 16-day EVI values greater than or equal to 500 metric showed high accuracy (94% to 98%) at a pixel scale and high R2 (0.96) for predicting total winter crop area planted.The rigour of the HANTS and the 16-day EVI values greater than or equal to 500 approaches was assessed when extrapolating over the entire Queensland cropping region for the 2005 and 2006 season. The combined early-season estimate of July and August produced high accuracy at pixel and regional scales with percent error of 8.6% and 26% below the industry estimates for 2005 and 2006 season, respectively. These satellite-derived crop area estimates were available at least four months before harvest, and deemed that such information will be highly sought after by industry in managing their risk. In discriminating among crops at pixel and regional scale, the HANTS approach showed high accuracy. Specific area estimates for wheat, barley and chickpea were, respectively, 9.9%, -5.2% and 10.9% (for 2005) and -2.8%, -78% and 64% (for 2006). Closer investigation suggested that the higher error in 2006 area estimates for barley and chickpea has emanated from the industry figures collected by the government.Area estimates of total winter crop, wheat, barley and chickpea resulted in R2 values of 0.92, 0.89, 0.82 and 0.52, when contrasted against the actual shire-scale data. A significantly high R2 (0.87) was achieved for total winter crop area estimates in Augusts across all shires for the 2006 season. Furthermore, the HANTS approach showed high accuracy in discriminating cropping area from non-cropping area and highlighted the need for accurate and up-to-date land use maps.This thesis concluded that time-series MODIS EVI imagery can be applied successfully to firstly, determine end-of-season crop area estimates at shire scale. Secondly, capturing canopy green-up through a novel metric (i.e. 16-day EVI values greater than or equal to 500) can be utilised effectively to determine early-season crop area estimates well before harvest. Finally, the extrapolability of these approaches to determine total and specific winter crop area estimates showed good utility across larger areas and seasons. Hence, it is envisaged that this technology is transferable to different regions across Australia. The utility of the remote sensing techniques developed in this study will depend on the risk agri-industry operates at within their decision and operating regimes. Trade-off between risk and value will depend on the accuracy and timing of the disseminated crop production forecast.

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Bilek, Meredith K. "Winter annual rye cover crops in no-till grain crop rotations impacts on soil physical properties and organic matter /." College Park, Md.: University of Maryland, 2007. http://hdl.handle.net/1903/7268.

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Thesis (M.S.) -- University of Maryland, College Park, 2007. Thesis research directed by: Dept. of Natural Resource Sciences and Landscape Architecture. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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18

Yi, Cuilin. "Management of Fusarium graminearum-inoculated crop residues effects on head blight, grain yield and grain quality of subsequent winter wheat crops /." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9686268.

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19

Dube, Ernest. "Soil fertility enhancement through appropriate fertilizer management on winter cover crops in a conservation agriculture system." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/d1001044.

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A study was carried out to determine the effects of oat (Avena sativa) and grazing vetch (Vicia darsycapa) winter cover crops and fertilizer application on SOM, phosphorus (P) pools, nutrient availability, nutrient uptake, maize yield and seedbanks of problematic weeds in an irrigated maize-based conservation agriculture (CA) system. A separate experiment was carried out to investigate the effects of the winter cover crops on nitrogen (N) management, N use efficiency and profitability. After four years of continuous rotation, the winter cover crops significantly (p<0.05) increased particulate SOM and hot water soluble carbon in the 0 – 5 and 5 – 20 cm soil depths. When fertilized, oat was better able to support SOM sequestration in water stable aggregates at 0 – 20 cm whilst grazing vetch was more effective at 20 – 50 cm. Where no fertilizer was invested, there were significant (p<0.01) reductions in biomass input and SOM on oat-maize and weedy fallow-maize rotations whereas vetch-maize rotations did not respond, both at 0 – 5 and 5 – 20 cm. Targeting fertilizer to the winter cover crop required less fertilizer, and yet gave a similar SOM response as targeting the fertilizer to the maize crop. In addition to increasing SOM in the surface soil (0 – 5 cm), the winter cover crops significantly (p<0.05) increased labile pools of P, including microbial P. The cover crops also significantly (p<0.05) increased maize P concentration during early growth, extractable soil P, Cu, Mn, and Zn but had no effect on Ca and K. Grazing vetch increased soil mineral N but reduced extractable soil Mg. Without fertilizer, there were sharp declines in maize grain yield on oat and weedy fallow rotations over the four year period, but less so, on the grazing vetch. Grazing vetch increased maize growth, grain yield response to N fertilizer, nitrogen use efficiency (NUE) and profitability for fertilizer rates below 180 kg N ha-1. Oat effects however on maize yield and NUE were generally similar to weedy fallow. Based on the partial factor productivity of N, the highest efficiencies in utilization of fertilizer N for maize yield improvement under grazing vetch and oat are obtained at 60 kg N ha-1 and would decline thereafter with any increases in fertilizer application rate. Grazing vetch gave N fertilizer replacement values of up to 120 kg N ha-1 as well as the highest marginal rates of return to increasing N fertilizer rate. The cover crops were more effective than the weedy fallow in reducing seedbank density of Digitaria sanguinalis, Eleusine indica, Amaranthus retroflexus and Datura stramonium at 0 – 5 cm soil depth, causing weed seed reductions of 30 - 70%. The winter cover crops however, selectively allowed emergence of the narrow leafed weeds; Cyperus esculentus and Digitaria sanguinalis in the maize crop. The findings of this study suggested that grazing vetch is suited for SOM improvement in low fertilizer input systems and that fertilizer is better invested on winter cover crops as opposed to maize crops. Oat, on the other hand, when fertilized, would be ideal for C sequestration in water stable aggregates of the surface soil. Grazing vetch is ideal for resource poor farmers who cannot afford mineral fertilizers as it gives grain yield improvement and high fertilizer replacement value. Grazing vetch can produce enough maize yield response to pay its way in the maize-based systems and oat may not require additional N than that applied to the weedy fallow. Phosphorus and Zn are some of the major limiting essential plant nutrients on South African soils and the winter cover crops could make a contribution. The cover crops also hasten depletion of some problematic weeds from seedbanks, leading to reduced weed pressure during maize growth.

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20

Pavuluri, Kiran. "Winter Barley as a Commodity Cover Crop in the Mid-Atlantic Coastal Plain and Evaluation of Soft Red Winter Wheat Nitrogen Use Efficiency by Genotype, and its Prediction of Nitrogen Use Efficiency through Canopy Spectral Reflectance in the Eastern US." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/47103.

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To understand the impact of N management on harvestable cover crop systems, seven research trials compared: 1) standard intensive management (SIM) (both fall and spring N application), 2) No fall N, a single spring N application, and 3) Cover N (no N application) effects on winter barley (Hordeum vulgare L.) plant biomass (PB), plant N uptake (PNU), grain yield, residual soil nitrate (RSN), and ammonium (RSA). In general, at winter dormancy, SIM resulted in increased PB and PNU but not RSN or RSA. At cover crop termination; SIM and the No fall N practices increased PNU, and at harvesting stage; they produced higher grain yields than the Cover N practice with little significant effect on RSN or RSA values, under normal climatic conditions. While overall yields for the No fall N treatment were lower (8%) than SIM yields, partial net return was similar due to decreased fertilizer input. Nitrogen use efficiency (NUE) of soft red winter wheat (SRWW) can be improved by characterizing genotypes for NUE using canopy spectral reflectance [(CSR), a cheap, rapid and non-destructive remote sensing tool]. The other objectives of this study were to evaluate the predictive potential of vegetative reflection indices for wheat nitrogen use efficiency (NUE) by genotype and the appropriate stages of CSR sensing. An elite panel of 281 regionally developed SRWW genotypes was screened under low and normal N regimes in two crop seasons for grain yield, N uptake, nitrogen use efficiency for yield (NUEY) and nitrogen use efficiency for protein (NUEP). The best models incorporating CSR data at wheat heading explained a significant proportion of total variation in grain yield, N uptake, NUEY and NUEP. Based on the best linear unbiased predictor values, genotypes were ranked and grouped into quartiles and the most efficient and responsive genotypes were identified. A significant proportion of the genotypes with high NUEY under high N conditions also had high NUEY under N stress; however, this was not the case for NUEP. Similarly, a significant proportion of genotypes with high NUEY also had high NUEP under both normal and low N conditions. Ph. D.

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21

Smith, Luke B. "Overseeding annual ryegrass and cereal rye into soybean for winter forage and as a cover crop for weed control and soil conservation." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4312.

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Thesis (M.S.)--University of Missouri-Columbia, 2005. The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (July 14, 2006) Includes bibliographical references.

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22

Stefani, Faé Giovani. "Integrating Livestock And Winter Annual Forages Into A No-Till Corn Silage System." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1228162408.

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23

Minnaar, Martha Maria. "Constraints on photosynthesis and antioxidant metabolism in winter and summer crops induced by sulphur dioxide fumigation / Martha Maria Minnaar." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9522.

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Recently, major advances have been made in developed countries elucidating the effects of air pollutants on crop plants. In contrast, similar studies on the effects of elevated SO2 concentrations on crops in developing countries such as South Africa are far less advanced. In South Africa, fossil fuel combustion is the main source of energy for most of the country. The tremendous increase in population size and consequental increase in energy demand has lead to considerable increases in fossil fuel burning. This phenomenon has lead to increases in tropospheric air pollutants such as SO2, NO2 and the secondary pollutant, O3. These increases, combined with climatic variations are subject of much concern in agricultural sectors. Fortunately, through many research studies done in European and other developed countries, threshold values have been established for selected crops in an attempt to mitigate the damage done by SO2 and other air pollutants. However, it is with due care that we apply these legislatory thresholds since the environmental conditions in the Southern hemisphere differs greatly from that of the Northern hemisphere. The main aims of this study was firstly to determine the physiological and biochemical basis of SO2 induced inhibition in the C3 and C4 crops, Brassica napus and Zea mays, respectively, and secondly, to study their response with special reference to photosynthesis. The combination of different SO2 levels and induced drought was also investigated. It was hypothesised that SO2 will impair the photosynthetic capacity of both Brassica napus and Zea mays test plants, but that with the addition of drought as co-stress, partial stomatal closure would lead to a mitigation of the SO2-effect on the photosynthetitc apparatus of the mentioned crops. Most of the research that has been done on air pollutants was short term studies, focused on generating dose-response data only over a few weeks of growth. Short term exposures do not answer questions on how initial constraints on photosynthesis could affect crops at a later stage, i.e. how and if these inhibitions affect the yield. In the present study, crops were grown for an entire growth season, from germination until harvest in open-top chambers (OTCs) in an attempt to link early photochemical inhibition to the reduction in yield. OTCs are internationally accepted as the best method to assess the effect of pollutant dosage on crops. Two crops, Brassica napus (C3) and Zea mays (C4) were cultivated and subjected to SO2 enriched air (50,100 and 200 ppb) for eight hours/day, seven days a week. Control plants only received carbon filtered (CF) air. An additional drought treatment was induced in half of the plants of each SO2 treatment. Experiments specifically focussed on the detrimental effect of SO2 on the photosynthetic capacity of the test plants. The photosynthetic capacity was evaluated using chlorophyll a fluorescence induction and photosynthetic gas exchange measurements in parallel, on a weekly basis. Analysis of the OJIP transients provided a number of parameters estimating the energy fluxes and ratios through photosystem II and the intersystem electron transport chain. Gas exchange parameters were deduced from CO2 response curves (A:Ci curves). The ability of the antioxidant metabolism to detoxify reactive oxygen species (ROS) was determined by measuring the POD activity and comparing it to the H2O2 content for Zea mays leaves over a period of nine weeks. Ultimately the cumulative effect of SO2 on the yield was evaluated by determining the shoot mass of Brassica napus and the cob mass of Zea mays. Elevated SO2 concentrations resulted in the partial destruction of chlorophyll pigments, leading to the formation of yellow chlorotic regions in both Brassica napus and Zea mays leaves. These visual effects appeared long after first changes occurred in photosystem II function or photosynthetic gas exchange. In addition to the visual damage, results revealed that elevated SO2 concentrations lead to an impaired photosynthetic capacity in both Brassica napus and Zea mays plants, especially concerning PSII function. The decline in photosynthetic capacity was mainly due to a loss in stomatal functionality, indicated as a reduction in the stomatal conductance for both Brassica napus and Zea mays plants. This was true for well watered and drought stressed treatments in both C3 and C4 crops. The reduced photosynthetic capacity was due to stomatal limitation and to a greater extent, biochemical (mesophyll) limitation. Mespohyll limitation was evident by the decrease in Rubisco activity (Brassica napus: C3) and PEPc activity (Zea mays: C4), in well watered and drought stress treatments. The inability to effectively regenerate ribulosebisphosphate (Brassica napus: C3) and phosphoenolpyruvate (Zea mays: C4) in well watered and drought stressed plants was another mesophyll limitation that contributed to the decline in photosynthesis. By in depth analysis of the chlorophyll a fluorescence transients according to the JIP test, the sites of inhibition in the photosynthetic electron transport chain were elucidated. The changes in the fluorescence transients revealed that the inhibition of the primary processes of photochemistry was mainly due to uncoupling of the oxygen evolving complex in well watered Zea mays and drought stressed Brassica napus plants and to the inhibition of the reduction of end electron acceptors beyond PSI in well watered and drought stressed Brassica napus plants and drought stressed Zea mays test plants. In Zea mays the source of the inhibition of the primary photochemistry through the decline in the reduction of end electron acceptors, was further investigated by in depth analysis of the I-P phase of the OJIP fluorescent transients, i.e. a segment only through photosystem I (PC→RE). The inhibition in well watered and drought stressed treatments were found, not only to be a result of the reduced pool size of electron acceptors, but was also due to a decline in the rate at which end electron acceptors were being reduced. These constraints on the functioning of the photosynthetic electron transport chain were reflected by the inhibition of CO2 assimilation rate, the decline in Rubisco activity (C3 plants) and PEPc anctivity (C4 plants), and decline in the regeneration rate of ribulosebisphosphate (C3 plants) and phosphoenolpyruvate (C4 plants) both due to the decreasing production of reduction equivalents in the light phase. This means that although the fluorescence transients are measured within one second in the dark adapted state, they provide a reliable measure of the whole photosynthetic electron transport chain. SO2 affected both the stomatal function and photosynthetic capacities of Zea mays and Brassica napus. The SO2-related stomatal closure resulted in a decrease in CO2 influx into the leaf and thus a decline in CO2 assimilation. This phenomenon was corroborated by the large decrease in water use efficience in Zea mays and Brassica napus. A marked SO2-concentration dependent decline in the shoot biomass in well watered and drought stressed Brassica napus was evident. Similarly, a reduction in yield occurred in Zea mays test plants, namely reductions in cob mass, in both well watered and drought stressed treatments. The data of the current investigation presented clearly indicate that marked impairment of photosynthesis and yield reduction in the crops, Zea mays and Brassica napus, occured at SO2 concentrations of 50 ppb.These findings proved the first hypothesis of this study to by true in that SO2 adversely affects the photosythetic capacity of crop plants. In Zea mays, more energy was expended towards growth than detoxification of sulphur metabolites. Due to this fact, Zea mays plants still grew to a considerable length with less energy available for cob formation. An increase in H2O2 content due to elevated SO2 concentrations, lead to the degradation of chlorophyll molecules and inhibition of the photosystems which consequentially inhibited the photosynthetic capacity of well watered and drought stressed Zea mays plants. The effectiveness of the antioxidant metabolism to remove H2O2 from mesophyll cells was displayed by the overall decrease in H2O2 content for WW and DS treatments after 9 weeks fumigation. This was achieved by the increased scavenging enzyme activity (increased POD activity) that effectively removed the ROS from the mesophyll cells. Ultimately the data showed that the C3 plant, Brassica napus, was more adversely affected by elevated SO2 concentrations, reducing the photosynthetic assimilation rate greatly. Drought stress however, ameliorated the damaging effect of SO2 on the photosystems to some extent, proving the second hypothesis true for Brassica napus plants. Zea mays plants however showed greater sensitivity towards elevated SO2 concentrations with the addition of drought as a costressor, while amelioration of the inhibitory effect through stomatal closure, proved not to be effective. These findings proved that the second hypothesis was thus only partially proven to be true, and only at low SO2 concentrations for Zea mays crop plants. Within natural environments there may be a magnitude of biotic and abiotic stresses being inposed on crops. The work done in this study is thus of great value to the agricultural sector in early determination of how multiple stressors (SO2 and drought in this case) might affect yield. Management plans can be implemented accordingly. This fact emphasises the magnitude of the relevance and the importance of multiple stress-response studies done on crops, such as the present. Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013

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24

Norris, Robert Brooke. "Winter Annual Cover Crops Interseeded into Soybean in Eastern Virginia: Influence on Soil Nitrogen, Corn Yield, and In-Season Soil Nitrogen Tests." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/51173.

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The diverse cropping system of eastern Virginia's coastal plain offers limited opportunity to establish winter annual cover crops (WCC) for nitrogen (N) scavenging. The winter fallow niche after double-crop or full-season soybean (Glycine max L. Merr.) encompasses the majority of acres left fallow. Our objective was to evaluate interseeded WCC N scavenging performance following soybean and N supplying capacity to subsequent corn (Zea mays L.). Field studies were conducted at four different locations in each of the two study years. The experimental design was split plot with cereal rye, hairy vetch, and RV mix WCC as main plots and ten fertilizer nitrogen (FN) rates in a factorial arrangement (0 and 45 kg FN ha-1 as starter; and 0, 45, 90, 135, and 180 kg FN ha-1 at sidedress) to corn as subplots. The highest N uptake for cereal rye at winter dormancy was 18 kg N ha-1, but the average was 6-7 kg N ha-1. At WCC termination average N uptake for cereal rye was 35 and 40 kg N ha-1 in 2013 and 2014, respectively. Average biomass dry matter (DM) at WCC termination for cereal rye, cereal rye + hairy vetch mix (RV mix), and hairy vetch was 2356, 2000, and 1864 kg ha-1 in 2013; and 2055, 2701, and 692 kg ha-1 in 2014, respectively. Average cereal rye N uptake was 35 kg N ha-1 in 2013 and 40 kg N ha-1 in 2014. Significant differences for residual soil nitrogen were most apparent for soil nitrate (NO3-N) at lower depths (15-30 and 30-60 cm) during WCC termination and in the upper 0-15 cm during corn growth stage (GS) V4 of both years. Corn grain yield plateau following hairy vetch WCC was 0.7 and 0.6 Mg ha-1 higher than when following cereal rye WCC at zero and 45 kg ha-1 starter FN, respectively. Average agronomic optimum FN rates (AONR) were 26 and 9 kg ha-1 lower following hairy vetch than cereal rye WCC at zero and 45 kg ha-1 starter FN, respectively. Estimated hairy vetch FN reductions by FN replacement and AONR difference methods were 48 and 18 kg FN ha-1 in plots receiving zero starter FN; and 58 and -43 kg FN ha-1 in plots receiving 45 kg ha-1 starter FN. In-season soil N tests did not offer adequate information in order to predict sidedress FN reductions. These findings suggest that cereal rye and RV mix have the potential to scavenge and conserve residual soil N and hairy vetch is more than capable to supply PAN to subsequent corn when interseeded into soybean. Master of Science

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25

Holland, Jonathan Eddison. "Changes in soil physical properties under raised bed cropping /." Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00002537.

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Ramsell, Jon. "Genetic variability of Wheat dwarf virus /." Uppsala : Dept. of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200797.pdf.

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Börjesdotter, Desirée. "Potential oil crops : cultivation of Barbarea verna, Barbarea vulgaris and Lepidium campestre /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5746-7.pdf.

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28

Madafiglio, Gregory Peter, University of Western Sydney, of Science Technology and Environment College, and School of Environment and Agriculture. "Population management of Raphanus raphanistrum L. (wild radish) by regulating seed production." THESIS_CSTE_CIT_Madafiglio_G.xml, 2002. http://handle.uws.edu.au:8081/1959.7/339.

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Raphanus raphanistrum L. (wild radish) is a widespread and economically problematic weed of winter crops including wheat (Triticum aestivum L.) in southern Australia. Management of the weed is achieved by a range of non-chemical and chemical techniques. Current management is failing to contain the weed, which is increasing in abundance and distribution. The characteristics of staggered recruitment, dormancy, rapid growth, competitive ability and high levels of seed production contribute to its persistence. The literature review concludes that weeds formed the basis for perpetuation of R. raphanistrum, a claim further investigated by simulation modeling. The effective management of R. raphanistrum should aim to achieve declining populations and this requires the integration of all factors that regulate seed production. Reducing seed production of R. raphanistrum in wheat can be achieved by applying herbicides at reproductive stages of development. This technique has been demonstrated to be an effective, safe and practical method of reducing seed production of R. raphanistrum in wheat. Reducing seed production of R. raphanistrum by herbicides applied at reproductive stages of development is a technique that can be incorporated into an integrated weed management program to improve control Doctor of Philosophy (PhD)

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29

Schappert, Alexandra [Verfasser], and Roland [Akademischer Betreuer] Gerhards. "Evaluating different management strategies to increase the effectiveness of winter cover crops as an integrated weed management measure / Alexandra Schappert ; Betreuer: Roland Gerhards." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2020. http://d-nb.info/1212509390/34.

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30

Gazola, Eduardo [UNESP]. "Desempenho de cultivares transgênicas de soja em sucessão a culturas de inverno em semeadura direta." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/86368.

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Made available in DSpace on 2014-06-11T19:22:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-28Bitstream added on 2014-06-13T19:07:33Z : No. of bitstreams: 1 gazola_e_me_botfca.pdf: 515907 bytes, checksum: 147c1f8c1d57f0773041fffb27a91fd1 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) O objetivo do trabalho foi avaliar o desempenho de cultivares transgênicas de soja (Glycine max (L.) Merrill) em sucessão a culturas de inverno na implantação do sistema de semeadura direta. O experimento foi conduzido na área experimental do Departamento de Produção Vegetal, na Faculdade de Ciências Agronômicas/UNESP, Campus de Botucatu-SP, durante o ano agrícola 2006/07. O delineamento experimental utilizado foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram representadas por cinco espécies cultivadas no inverno, aveia branca (Avena sativa L.), nabo forrageiro (Raphanus sativus L.), cevada (Hordeum vulgare L.), trigo (Triticum aestivum L.) e ervilha forrageira (Pisum sativum L.) e área de pousio (vegetação espontânea). As subparcelas foram constituídas por seis cultivares de soja (BRS 243 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR, BRS 256 RR e BRS 244 RR), cedidas pela Embrapa SNT-EN.LDB, totalizando 36 tratamentos. Foram avaliadas, nas espécies de inverno, a massa da matéria seca da parte aérea e a produtividade de grãos, enquanto na soja as características agronômicas como florescimento, ciclo, alturas de plantas e de inserção da primeira vagem, população final de plantas, grau de acamamento, número de vagens chochas, número de nódulos por planta, massa da matéria seca dos nódulos por planta, além dos componentes da produção número de vagens por planta, número de grãos por vagem, massa de 100 grãos e a produtividade. Foi avaliado, também, o teor foliar dos macronutrientes N, P, K, Ca, Mg e S das plantas de soja por meio da diagnose foliar.A cevada, entre as culturas de inverno, foi a que apresentou os maiores valores de produtividade de grãos e de massa de matéria seca, não diferindo, na ultima avaliação da aveia, da ervilha forrageira e do nabo forrageiro. As características... The objective of this research was to evaluate crop yield and some characteristics and yield components of transgenic soybean cultivars sown after different winter cover crops in the first year under no tillage system. The present work was carried out on the experimental area of the “Departamento de Ciências Agronômicas”, “Faculdade de Ciências Agronômicas/UNESP”, Botucatu-SP, in 2006/2007, as a partnership with Embrapa SNT – EN.LDB (Embrapa serviços de negócios para transferência de tecnologia – Escritório de negócios de Londrina). The experimental design was the completely randomized block with split plots and four replications. The main plots consisted of five winter cover crops, white oat (Avena sativa L.), forage turnip (Raphanus sativus L.), barley (Hordeum vulgare L.), wheat (Triticum aestivum L.) and ground pea (Pisum sativum L.) and an area under fallow (spontaneous vegetation). The subplots consisted of six soybean cultivars (BRS 243 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR, BRS 256 RR and BRS 244 RR) which were granted by Embrapa SNT-EN.LDB, totaling 36 treatments. Shoot dry matter and grain yield were evaluated for each winter crop. While the experiment had been carried out, some soybean agronomic characteristics were evaluated like flowering, cycle, first pod insertion and plant height, final population, bending, number of nodes per plant, nodes dry matter per plant and grain yield. Yield components, weight of 100 grains, number of pods and aborted grains per plant and grains per pod were evaluated. N, P, K, Ca, Mg and S levels in soybean tissue werealso evaluated through foliar diagnosis. Among all winter crops evaluated, barley was the one that showed higher values for grain yield and dry matter, however, it did not differ from oat, ground pea and forage turnip in the last evaluation. Variance analysis for agronomic characteristics... (Complete abstract click electronic access below)

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Yano, Élcio Hiroyoshi [UNESP]. "Sucessão de culturas em sistemas integrados de produção." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/101939.

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Made available in DSpace on 2014-06-11T19:31:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-19Bitstream added on 2014-06-13T20:42:18Z : No. of bitstreams: 1 yano_eh_dr_botfca.pdf: 978840 bytes, checksum: 128042dc305593b9ba3a3b56612214a0 (MD5) O uso do sistema plantio direto tem proporcionado uma série de transformações nas cadeias produtivas devido ao planejamento e à diversificação das atividades agrícolas com as ráticas racionais, o que vem aumentando a produção de grãos e carne no país. Devido à sua grande extensão territorial, as condições climáticas são irregulares, algumas regiões caracterizam-se por elevadas temperaturas, com chuvas de grande intensidade no verão e inverno frio e seco, ocasionando dificuldades na formação de cobertura morta com baixo custo. Uma das espécies utilizadas para esta finalidade são as gramíneas, que, integradas no sistema de rotação e sucessão de culturas, garantem a cobertura do solo por períodos mais prolongados. Este trabalho objetivou analisar o desempenho energético dos sistemas de manejo do solo e da cobertura com a otimização do número de culturas em sucessão para a produção de grãos e feno, e obtenção de cobertura de solo para região de inverno seco. O experimento foi instalado e conduzido em condições de campo, nos anos agrícolas de 2002/2003 e 2003/2004, na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - Campus de Botucatu/ UNESP, num Nitossolo Vermelho Distrófico, cultivado há 7 anos com os mesmos tratamentos de preparo do solo: arado de disco + 2 gradagens leves; escarificador com disco de corte e rolo destorroador; sistema plantio direto no verão; semeadura direta das culturas de inverno com aveia preta e sorgo e tratamento testemunha composto por pousio. O delineamento experimental utilizado foi de blocos casualizados em esquema fatorial (3x3), com quatro repetições. Os resultados obtidos permitiram verificar que, independente das espécies utilizadas, a porcentagem de cobertura do solo mostrou-se superior no sistema plantio direto quando comparado aos demais... The use of the no-tillage system has been providing a series of transformations in the productive chains because of the planning and diversification of the agricultural activities with rational practices, comes increasing the production of grains and meat in the country. Due to your large territorial extension, the climatic conditions are irregular, some areas are characterized by high temperatures, with rains of intensity in the summer and cold and dry winter, causing difficulties in the formation of dead covering with low cost. One the species used for this purpose they are grasses that, integrated in the rotation and succession crops systems, give security to soil coverage for more lingering periods. The objective of this research was to analyze the energy acting of planting systems and soil coverage with the optimize of the number of cultures in succession for the production of grains and hay, and obtaining soil covering for area of dry winter. The experiment was installed and led in field conditions, in the agricultural years 2002/2003 and 2003/2004, in The Lageado Experimental Farm, Unesp, Campus of Botucatu, on an Alfisol , cultivated 7 years ago with the same treatments planting: disk plow + 2 leveling disk harrowing; chisel plow with cut disk and roll; system no-tillage in the summer; no-tillage in the winter with dark oat and sorghum and testifies treatment composed by winter fallow. The experimental design was the split plot in factorial outline (3x3), with four replications. Results showed that, independent of the used species, the percentage of soil coverage was superior in the system no-tillage when compared to the others. The soybean planting prepared with minimum tillage it provided larger integrated force of traction, potency demand, fuel consumption, slip of traction wheel and smaller displacement speed...(Complete abstract click electronic access below)

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Vaitelytė, Birutė. "Patterns of distribution of insect pests (Ceutorhynchus spp., dasineura brassicae) on stems and pods of winter and spring oil seed rape crops and damage done by these pests." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20141124_140853-79060.

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Research objective. The study was aimed to establish development and distribution patterns of cabbage stem weevil (Ceutorhynchus pallidactylus), cabbage seed weevil (C. obstrictus) and Brassica pod midge (Dasineura brassicae) in winter and spring oilseed rape crops, to estimate insect damage, to compare the efficacy of insecticides of different mode of action and to determine the optimal timing of insecticide application. Research tasks. 1. To determine species abundance and diversity of Ceutorhynchus spp. infesting oilseed rape crops. 2. To study cabbage stem weevil’s (C. pallidactylus) biology (migration activity of adult insects, embryonic and post-embryonic development) in winter and spring oilseed rape crops and to estimate insect injury. 3. To establish the patterns of distribution of adults of cabbage seed weevil (C. obstrictus) as well as those of embryonic and post-embryonic development in winter and spring oilseed rape crops and to estimate insect injury. 4. To explore the biology of Brassica pod midge (Dasineura brassicae), to identify distribution and development peculiarities and damage done to winter and spring oilseed rape. 5. To determine biological and economic efficacy and optimal application timing of insecticides of different mode of action against stem (C. pallidactylus) and pod (C. obstrictus and D. brassicae) insect pests in winter and spring oilseed rape. Tyrimų tikslas. Nustatyti kopūstinių stiebinių paslėptastraublių (Ceutorhynchus pallidactylus), ankštarinių paslėptastraublių (C. obstrictus) ir ankštarinių gumbauodžių (Dasineura brassicae) plitimo ir vystymosi ypatumus žieminiuose ir vasariniuose rapsuose bei žalingumą, palyginti skirtingo poveikio insekticidų efektyvumą ir nustatyti optimalų insekticidų naudojimo laiką nuo šių kenkėjų. Tyrimų uždaviniai. 1. Nustatyti žieminių ir vasarinių rapsų pasėliuose plintančių paslėptastraublių (Ceutorhynchus spp.) rūšių gausumą ir įvairovę. 2. Ištirti kopūstinių stiebinių paslėptastraublių (C. pallidactylus) biologiją (suaugėlių migracijos aktyvumą, embrioninį ir poembrioninį vystymąsi) žieminiuose ir vasariniuose rapsuose, įvertinti šių kenkėjų žalingumą. 3. Nustatyti ankštarinių paslėptastraublių (C. obstrictus) suaugėlių paplitimo, embrioninio ir poembrioninio vystymosi ypatumus žieminiuose ir vasariniuose rapsuose bei jų žalingumą. 4. Ištirti ankštarinių gumbauodžių (Dasineura brassicae) biologiją, nustatyti jų žalingumą bei vystymosi ypatumus žieminiuose ir vasariniuose rapsuose. 5. Nustatyti skirtingo poveikio insekticidų biologinį ir ūkinį efektyvumą ir optimalų jų naudojimo laiką nuo stiebų (C. pallidactylus) ir ankštarų kenkėjų (C. obstrictus ir D. brassicae) žieminiuose ir vasariniuose rapsuose.

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Gazola, Eduardo 1982. "Desempenho de cultivares transgênicas de soja em sucessão a culturas de inverno em semeadura direta /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/86368.

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Orientador: Cláudio Cavariani Banca: Leandro Borges Lemos Banca: Luz Carlos Miranda Resumo: O objetivo do trabalho foi avaliar o desempenho de cultivares transgênicas de soja (Glycine max (L.) Merrill) em sucessão a culturas de inverno na implantação do sistema de semeadura direta. O experimento foi conduzido na área experimental do Departamento de Produção Vegetal, na Faculdade de Ciências Agronômicas/UNESP, Campus de Botucatu-SP, durante o ano agrícola 2006/07. O delineamento experimental utilizado foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram representadas por cinco espécies cultivadas no inverno, aveia branca (Avena sativa L.), nabo forrageiro (Raphanus sativus L.), cevada (Hordeum vulgare L.), trigo (Triticum aestivum L.) e ervilha forrageira (Pisum sativum L.) e área de pousio (vegetação espontânea). As subparcelas foram constituídas por seis cultivares de soja (BRS 243 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR, BRS 256 RR e BRS 244 RR), cedidas pela Embrapa SNT-EN.LDB, totalizando 36 tratamentos. Foram avaliadas, nas espécies de inverno, a massa da matéria seca da parte aérea e a produtividade de grãos, enquanto na soja as características agronômicas como florescimento, ciclo, alturas de plantas e de inserção da primeira vagem, população final de plantas, grau de acamamento, número de vagens chochas, número de nódulos por planta, massa da matéria seca dos nódulos por planta, além dos componentes da produção número de vagens por planta, número de grãos por vagem, massa de 100 grãos e a produtividade. Foi avaliado, também, o teor foliar dos macronutrientes N, P, K, Ca, Mg e S das plantas de soja por meio da diagnose foliar.A cevada, entre as culturas de inverno, foi a que apresentou os maiores valores de produtividade de grãos e de massa de matéria seca, não diferindo, na ultima avaliação da aveia, da ervilha forrageira e do nabo forrageiro. As características... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: The objective of this research was to evaluate crop yield and some characteristics and yield components of transgenic soybean cultivars sown after different winter cover crops in the first year under no tillage system. The present work was carried out on the experimental area of the "Departamento de Ciências Agronômicas", "Faculdade de Ciências Agronômicas/UNESP", Botucatu-SP, in 2006/2007, as a partnership with Embrapa SNT - EN.LDB (Embrapa serviços de negócios para transferência de tecnologia - Escritório de negócios de Londrina). The experimental design was the completely randomized block with split plots and four replications. The main plots consisted of five winter cover crops, white oat (Avena sativa L.), forage turnip (Raphanus sativus L.), barley (Hordeum vulgare L.), wheat (Triticum aestivum L.) and ground pea (Pisum sativum L.) and an area under fallow (spontaneous vegetation). The subplots consisted of six soybean cultivars (BRS 243 RR, BRS 245 RR, BRS 247 RR, BRS 255 RR, BRS 256 RR and BRS 244 RR) which were granted by Embrapa SNT-EN.LDB, totaling 36 treatments. Shoot dry matter and grain yield were evaluated for each winter crop. While the experiment had been carried out, some soybean agronomic characteristics were evaluated like flowering, cycle, first pod insertion and plant height, final population, bending, number of nodes per plant, nodes dry matter per plant and grain yield. Yield components, weight of 100 grains, number of pods and aborted grains per plant and grains per pod were evaluated. N, P, K, Ca, Mg and S levels in soybean tissue werealso evaluated through foliar diagnosis. Among all winter crops evaluated, barley was the one that showed higher values for grain yield and dry matter, however, it did not differ from oat, ground pea and forage turnip in the last evaluation. Variance analysis for agronomic characteristics... (Complete abstract click electronic access below) Mestre

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Piano, Jeferson Tiago. "Manejos de cereais de inverno em sistema de integração lavoura pecuária e sua influencia sobre as propriedades físicas do solo, resíduos culturais e plantas daninhas." Universidade Estadual do Oeste do Paraná, 2014. http://tede.unioeste.br:8080/tede/handle/tede/1252.

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Made available in DSpace on 2017-07-10T17:36:57Z (GMT). No. of bitstreams: 1 2014_Diss_Jeferson_Tiago_Piano.pdf: 1013753 bytes, checksum: d7a290e824e835fc82cc2e6dc888c48f (MD5) Previous issue date: 2014-02-27 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The study aimed and was conducted to evaluate the effects of different managements of cereals grown and subjected to grazing on soil physical properties, quantity and nutrient content of winter crop residues, besides the incidence of weeds. The study was conducted in the experimental area of the State University of West Paraná - Campus Marechal Cândido Rondon in Dystrophic Oxisol. The experimental design was randomized blocks in split-plot, with four replications. The treatments consisted of three different winter cereals (oats IPR 126, wheat and triticale BRS Tarumã IPR 111) in bands A and managements in B bands: ungrazed , one grazing and two grazing. With respect to soil physical properties (macroporosity, microporosity, total porosity and density), determined by collecting soil core, it was found that they suffered minor influences, with the exception of soil density due to treatments, evaluations after harvest of winter cereals and soybeans. The resistance to penetration, determined with an impact penetrometer, was influenced by the crop after harvest of winter cereals and by management after the soybean harvest in 20-25 cm layer and 25-30 cm depth. The different winter cereals used influenced the amount of remaining organic waste, the levels of C and P in the C:N. The largest amount of crop residues was found that the management was not performed grazing. Through the inventory square method, were identified 11 families and 16 species of weeds in the area, highlighting the Poaceae and Asteraceae families O estudo foi conduzido com o objetivo de avaliar os efeitos de diferentes manejos de cereais de inverno cultivados e submetidos ao pastejo, sobre as propriedades físicas do solo, a quantidade e os teores de nutrientes dos resíduos culturais, além da incidência de plantas daninhas. O trabalho foi desenvolvido em área experimental da Universidade Estadual do Oeste Paraná - Campus Marechal Cândido Rondon, em LATOSSOLO VERMELHO Distroférrico (LVdf). O delineamento experimental utilizado foi o de blocos casualizados em esquema de faixas, com quatro repetições. Os tratamentos foram constituídos de três diferentes cereais de inverno (aveia IPR 126, trigo BRS Tarumã e triticale IPR 111) nas faixas A e os manejos nas faixas B: sem pastejo, um pastejo e dois pastejos. Com relação às propriedades físicas do solo (macroporosidade, microporosidade, porosidade total e densidade), determinadas com anéis volumétricos, constatou-se que estas sofreram pequenas influencias, com exceção da densidade do solo, devido aos tratamentos empregados, nas avaliações após a colheita dos cereais de inverno e da cultura da soja. A resistência do solo à penetração, determinada com penetrometro de impacto, foi influenciada pela cultura, após a colheita dos cereais de inverno e, pelo manejo após a colheita da soja, na camada de 20 a 25 cm e de 25 a 30 cm de profundidade. Os diferentes cereais de inverno utilizados influenciaram na quantidade de resíduos orgânicos remanescente, nos teores de C, P e na relação C:N. A maior quantidade de resíduos culturais foi encontrada no manejo em que não foi realizado pastejo. Através do método do quadrado inventário, foram identificadas 11 famílias e 16 espécies, de plantas daninhas na área, destacando-se as famílias Poaceae e Asteraceae

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Yano, Élcio Hiroyoshi 1974. "Sucessão de culturas em sistemas integrados de produção /." Botucatu : [s.n.], 2005. http://hdl.handle.net/11449/101939.

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Orientador: Sérgio Hugo Benez Banca: Maria Helena Moraes Banca: Luiz Malcoln Mano de Mello Banca: Edgard Jardim Rosa Junior Banca: Rubens Siqueira Resumo: O uso do sistema plantio direto tem proporcionado uma série de transformações nas cadeias produtivas devido ao planejamento e à diversificação das atividades agrícolas com as ráticas racionais, o que vem aumentando a produção de grãos e carne no país. Devido à sua grande extensão territorial, as condições climáticas são irregulares, algumas regiões caracterizam-se por elevadas temperaturas, com chuvas de grande intensidade no verão e inverno frio e seco, ocasionando dificuldades na formação de cobertura morta com baixo custo. Uma das espécies utilizadas para esta finalidade são as gramíneas, que, integradas no sistema de rotação e sucessão de culturas, garantem a cobertura do solo por períodos mais prolongados. Este trabalho objetivou analisar o desempenho energético dos sistemas de manejo do solo e da cobertura com a otimização do número de culturas em sucessão para a produção de grãos e feno, e obtenção de cobertura de solo para região de inverno seco. O experimento foi instalado e conduzido em condições de campo, nos anos agrícolas de 2002/2003 e 2003/2004, na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - Campus de Botucatu/ UNESP, num Nitossolo Vermelho Distrófico, cultivado há 7 anos com os mesmos tratamentos de preparo do solo: arado de disco + 2 gradagens leves; escarificador com disco de corte e rolo destorroador; sistema plantio direto no verão; semeadura direta das culturas de inverno com aveia preta e sorgo e tratamento testemunha composto por pousio. O delineamento experimental utilizado foi de blocos casualizados em esquema fatorial (3x3), com quatro repetições. Os resultados obtidos permitiram verificar que, independente das espécies utilizadas, a porcentagem de cobertura do solo mostrou-se superior no sistema plantio direto quando comparado aos demais...(Resumo completo, clicar acesso eletrônico abaixo) Abstract: The use of the no-tillage system has been providing a series of transformations in the productive chains because of the planning and diversification of the agricultural activities with rational practices, comes increasing the production of grains and meat in the country. Due to your large territorial extension, the climatic conditions are irregular, some areas are characterized by high temperatures, with rains of intensity in the summer and cold and dry winter, causing difficulties in the formation of dead covering with low cost. One the species used for this purpose they are grasses that, integrated in the rotation and succession crops systems, give security to soil coverage for more lingering periods. The objective of this research was to analyze the energy acting of planting systems and soil coverage with the optimize of the number of cultures in succession for the production of grains and hay, and obtaining soil covering for area of dry winter. The experiment was installed and led in field conditions, in the agricultural years 2002/2003 and 2003/2004, in The Lageado Experimental Farm, Unesp, Campus of Botucatu, on an Alfisol , cultivated 7 years ago with the same treatments planting: disk plow + 2 leveling disk harrowing; chisel plow with cut disk and roll; system no-tillage in the summer; no-tillage in the winter with dark oat and sorghum and testifies treatment composed by winter fallow. The experimental design was the split plot in factorial outline (3x3), with four replications. Results showed that, independent of the used species, the percentage of soil coverage was superior in the system no-tillage when compared to the others. The soybean planting prepared with minimum tillage it provided larger integrated force of traction, potency demand, fuel consumption, slip of traction wheel and smaller displacement speed...(Complete abstract click electronic access below) Doutor

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Seben, Junior Getulio de Freitas. "Resistência tênsil relacionada com atributos de um Latossolo sob sistema de semeadura direta /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/88305.

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Resumo: A avaliação da estrutura do solo pode ser realizada por um conjunto de atributos específicos e suas inter-relações. Assim, os objetivos foram: i) quantificar a resistência tênsil de agregados (RT), friabilidade do solo (FR), e teor de carbono (C), diâmetro médio ponderado (DMP), índice de estabilidade de agregados (IEA) e a densidade do solo (DS) e verificar a influência dos demais atributos na RT e FR; ii) avaliar a influência do formato dos agregados na RT e FR. O delineamento foi em blocos casualizados, em faixas, com três repetições. Os tratamentos foram constituídos de três seqüências de culturas de verão (milho, soja e rotação soja/milho) e sete culturas de inverno (milho, girassol, nabo forrageiro, milheto, guandu, sorgo e crotalária). Em cada parcela foram coletados quatro blocos de solo com dimensões de 10x20x15 cm de altura, comprimento e largura, respectivamente; destes blocos selecionaram-se agregados com diâmetro entre 19,0 e 12,5 mm. Foram avaliados a influência do formato dos agregados na determinação da RT e FR e a influência das seqüências de culturas na RT, FR, teor de água e de C, IEA, DMP e DS. Os dados foram submetidos à análise de variância e as médias dos tratamentos comparadas pelo teste de Tukey. Realizou-se correlação de Pearson entre a RT e FR com os demais atributos. Foi constatado que os agregados com base plana proporcionaram uma menor variabilidade em comparação aos esféricos, conferindo maior acurácia a medida da RT e que as seqüências de culturas não influenciaram o teor de C e a FR, mas afetaram a RT, o IEA, o DMP e a DS. Também foi constatado que a RT correlacionou-se positivamente com o IEA, DMP e C Abstract: Soil structure can be evaluated by a set of specific attributes and their correlations. The objectives of this study were to: i) quantify aggregate tensile strength (TS), soil friability (SF), carbon content (C), mean pondered diameter (MPD), aggregate stability index (ASI) and bulk density (BD) as well as evaluate the effects of the other attributes on TS and SF; ii) determine the influence of aggregate shape on TS and SF. The experimental design was the completely randomized block arranged in strip plots with three replications. Treatments consisted of three sequences of summer crops (corn, soybean and the rotation soybean/corn) combined with seven winter crops (corn, sunflower, forage turnip, millet, pigeon pea, sorghum and sunnhemp). Four blocks of soil measuring 10x20x15 cm of height, length and width, respectively, were taken from each plot. Then, aggregates with diameters of 19.0 and 12.5 mm were taken from them. The effects of aggregate shape on TS and SF were evaluated. Also, the influence of the crop rotations on TS, SF, C content, ASI, MPD and BD was determined. The results were submitted to variance analysis (F test) and means were compared by the Tukey test (p < 0.10). Pearson linear test was applied to evaluate the correlation between TS/SF and the other soil attributes. Filed aggregates provide lower variability compared to the spherical ones, resulting in higher accuracy to measure TS. The crop rotations did not affect C content and SF, but positively influenced TS, ASI, MPD and BD. Also, TS showed positive correlation with ASI, MPD and C content Orientador: José Eduardo Corá Coorientador: Carolina Fernandes Banca: Marcílio Vieira Martins Filho Banca: Zigomar Menezes de Souza Mestre

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Bertoncelli, Patricia. "Inoculação, manejo do nitrogênio e decomposição dos resíduos vegetais de cereais de inverno na produção de grãos e silagem de milho." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/5113.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico The quest for greater productivity and concern for sustainability, it makes the constant search for alternatives that obtain high productivity sustainably and nutrient cycling, biological nitrogen fixation and proper N fertilization some of these alternatives. In order to validate these alternatives aim with this work was to verify the influence of inoculation and nitrogen management in winter cereals, rates of decomposition of plant residues and its influence on the yield of grain and corn silage. The work consists of three chapters with the first entitled "effect of inoculation with Azospirillum brasilense and seed treatment in the initial development of four cultivars of wheat" which aims to assess the development and initial establishment of wheat cultivars subjected to treatment and inoculating seeds with Azospirillum brasilense bacteria. The second titled "inoculation, waste straw and nitrogen on grain yield and quality of corn silage " aims to evaluate the influence of applying Azospirillum brasilense associated with different levels of nitrogen on yield components and quality of silage corn in no-till crop residues on different system. The third "different decomposition of crop residues on different nitrogen rates and application Azospirillum brasilense" aims to obtain a characterization of the decomposition of the macronutrients of different crops / cultivars, under the influence of different nitrogen and inoculant application based Azospirillum. The different crop residues have different productivities as well as provide change in silage quality. The application of Azospirillum brasilense causes increase in corn yield, change in the initial development of wheat seedlings, as well as providing variation in the decomposition of plant residues. The use of seed treatment affects initial growth of wheat seedlings, however, they have a compensatory gain minimizing this effect. A busca pela maior produtividade e a preocupação com a sustentabilidade, faz com que as seja constante a busca por alternativas que obtenham alta produtividade de forma sustentável sendo a ciclagem de nutrientes, a fixação biológica de nitrogênio e o uso adequado da adubação nitrogenada algumas dessas alternativas. A fim de validar essas alternativas objetivou-se com esse trabalho verificar a influência da inoculação e manejo do nitrogênio em cereais de inverno, taxas de decomposição dos resíduos vegetais e sua influência sobre as produtividades de grãos e silagem de milho. O trabalho consiste em três capítulos sendo o primeiro intitulado efeito da inoculação com Azospirillum brasilense e tratamento de sementes sob o desenvolvimento inicial de quatro cultivares de trigo o qual tem por objetivo avaliar o desenvolvimento e estabelecimento inicial de cultivares de trigo submetido ao tratamento de sementes e inoculação com bactérias de Azospirillum brasilense. O segundo intitulado inoculação, resíduos de palhada e doses de nitrogênio sob a produtividade de grãos e qualidade de silagem de milho tem por objetivo avaliar a influência da aplicação de Azospirillum brasilense associada a diferentes doses de nitrogênio nos componentes de rendimento e na qualidade de silagem de milho em sistema de plantio direto sobre diferentes resíduos culturais. O terceiro decomposição de diferentes resíduos culturais sobre diferentes doses de nitrogênio e aplicação de Azospirillum brasilense tem por objetivo obter uma caracterização da decomposição dos macronutrientes de diferentes culturas/cultivares, sob a influência de diferentes doses de nitrogênio e aplicação de inoculante a base de Azospirillum. Os diferentes resíduos culturais apresentam proporcionam diferentes produtividades assim como alteração na qualidade da silagem. A aplicação de Azospirillum brasilense proporciona aumento na produtividade de milho, alteração no desenvolvimento inicial de plântulas de trigo, assim como proporciona variação na decomposição de resíduos vegetais. O uso do tratamento de semente afeta o desenvolvimento inicial de plântulas de trigo, no entanto, as mesmas possuem ganho compensatório minimizando esse efeito.

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Zhang, Shulan. "Soil hydraulic properties and water balance under various soil management regimes on the Loess Plateau, China /." Umeå : Dept. of Forest Ecology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005126.pdf.

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Kühlsen, Nils. "Empfehlungen von Winterweizensorten im Organischen Landbau über die Kleberproteinfraktionen und deren Einfluß auf die Backqualität." Bonn : Institut für Lebensmittelwissenschaft und Lebensmittelchemie, der Rheinischen Friedrich-Wilhelms-Universität, 2001. http://hss.ulb.uni-bonn.de:90/ulb_bonn/diss_online/landw_fak/2001/kuehlsen_nils/0198.pdf.

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Silva, Denis Augusto da. "EFEITO DE SUCESSÕES DE CULTURAS NA QUALIDADE DO SOLO EM UM SISTEMA PLANTIO DIRETO." UNIVERSIDADE FEDERAL DA GRANDE DOURADOS, 2007. http://tede.ufgd.edu.br:8080/tede/handle/tede/132.

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Made available in DSpace on 2016-02-26T12:59:45Z (GMT). No. of bitstreams: 1 DenisAugustoSilva.pdf: 537885 bytes, checksum: 3ebbc55aaae7de28c15067a8aac8d9e7 (MD5) Previous issue date: 2007-11-29 Soil physical degradation, like compaction, reduces water movement and root development. Soil structure is considered one of most importance to agriculture, because other fundamental properties are closed related to it in soil-plant relationship. The objective of this study was to evaluate the effect of crop sequences on physical attributes of soil. The research was realized in 2004/05 and 2005/06 growing seasons, in a Typic Clayey Rhodic Hopludox, under 8 years of no-tillage system, at Universidade Federal da Grande Dourados Campus. The experiment was a randomized complete block design, with three replications. Treatments were constituted by cover crops: sunflower (Helianthus annuus L.), sunnhemp (Crotalaria juncea L.), hairy vetch (Vicia villosa Roth), mixture of sunnhemp + black oat (Avena strigosa Schreb), and mixture of black oat + hairy vetch + oilseed radish (Raphanus sativus L. Var. oliferus Metzg). Differences were not observed in soil density, in porosity and in aggregation rate when soil cultivated with sunflower, hairy vetch, sunnhemp, or the mixtures. Differences were observed in soil physical properties between 0-5 cm layer and 5-10cm 10-20cm layers, but no differences between 5-10 cm and 10-20cm layers. Soil carbon trend to higher contents in crops with high production of surface residues, although carbon contents differences were insufficient to modify aggregation. Corn yield was unattached from previous crops, but in the year, where rain was better distributed, it was higher A degradação física dos solos, como a compactação, reduz a movimentação de água e o crescimento de raízes. A estrutura do solo é considerada como uma de suas mais importantes propriedades do ponto de vista agrícola, pois a ela estão relacionadas outras propriedades fundamentais nas relações solo-planta. Com o objetivo de se avaliar o efeito de culturas antecessoras nos atributos físicos do solo realizou-se este trabalho em um Latossolo Vermelho Distroférrico, textura muito argilosa, nas safras 2004/05 e 2005/06, na Universidade Federal da Grande Dourados em uma área há 8 anos sob plantio direto. O delineamento experimental foi em blocos completos casualizados com três repetições. Foram avaliados sistemas de culturas com as espécies girassol (Helianthus annuus L.), crotalária (Crotalaria juncea L.), ervilhaca peluda (Vicia villosa Roth), consórcio de crotalária e aveia preta (Avena strigosa Schreb) e consórcio de aveia preta, ervilhaca peluda e nabo forrageiro (Raphanus sativus L. var. oleiferus Metzg). Não foi observada diferenças significativas na densidade do solo, na porosidade e nos índices de agregação quando o solo foi cultivado com girassol, ervilhaca peluda, crotalaria juncea, ou os consórcios. Houve diferenças nos atributos físicos do solo entre a camada de 0-5 cm e as camadas 5-10 e 10-20 cm, porém, sem diferenças entre as camadas 5-10 e 10-20 cm. Houve uma tendência a maiores teores de carbono do solo em cultivos com alta produção de resíduos, mas as diferenças nos teores de carbono não foram suficientes para modificar a agregação do solo.

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Fornari, Mayara Regina. "Solos com diferentes sistemas de manejo e rotação de culturas em longo prazo: flutuações nas frações de fósforo." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/11557.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES An exploration for economical and sustainable alternatives, to maximize the use of phosphorus present in soil has emphasized against the decline in phosphate fertilizer production reserves. Different physical and chemical characteristics of the soil can be affected by soil preparation and planting of different crops in crop rotation system. However, their effects on soil phosphorus dynamics are not fully clarified, especially in highly weathered regions such as southern Brazil.The objective of this work was to evaluate the influence of the No Tillage System (NTS) and Conventional Tillage System (CTS), associated with different winter cover crops on phosphorus fractions in very clayey oxisol. The experimental area is located at the Experimental Station of the Agronomic Institute of Paraná, in Pato Branco−Paraná.The main plots were treated with different cover crops: ryegrass (Lolium multiflorum L.), rye (Secale cereale L.), common vetch (Vica sativa L.), hairy vetch (Vicia villosa Roth) + black oat (Avena strigosa Schreb), forage turnip (Raphanus sativus L.), wheat and fallow, while (Triticum aestivum L.), in subplots two soil preparation systems (NTS and CTS) were used.Soil samples were collected from 0 to 0.10m depthwith three distinct periods: corn post−harvest (2014-2015), flowering of cover crops (2015) and soybean flowering (2015-2016).The methodologies used for the analyzes were: potentially available P by Mehlich 1 and anion exchange resins (AER); stored P in soil microbial biomass (SMB) through fumigation with chloroform; NaOH (0.5 mol l−1) extractable P, total organic P (Po) by ignition at 550 ° C in muffle furnace and subsequent extraction with sulfuric acid; Total P (Ptotal) by the block digestion method; Total inorganic P (Pi) by difference between P Total and Po total.The NTS in relation to CTS had the highest averages of P extracted in all fractions analyzed.Wheat had the lowest averages of available P by Mehlich (7.9 mg kg−1) and P stored in the SMB (30.8 mg kg−1). The organic P (Po) in both SCC and SPD corresponded to 30% of total P. It was concluded that the cultivation of the soil no tillage with hibernal plants and with high yields of soil, part of the P inorganic applied can accumulate in the form of moderately labile organic. Os efeitos de diferentes preparos de solo e de plantas cultivadas na dinâmica do fósforo no solo ainda não estão totalmente esclarecidos, especialmente em solos altamente intemperizados sob condições subtropicais, como os da região Sul do Brasil. Somando-se a esse cenário, ocorre o declínio das reservas de matéria-prima para a produção de fertilizante fosfatados. Assim, tem se acentuado a busca por alternativas para aumentar a capacidade de produção e melhorar as condições físicas, biológicas e químicas do solo, de maneira econômica e sustentável. O objetivo desse trabalho foi avaliar a influência do Sistema Plantio Direto (SPD) e do Sistema Cultivo Convencional (SCC), ambos já consolidados, aliados a diferentes plantas de coberturas de inverno, nas frações de P num Latossolo Vermelho muito argiloso. A área experimental está localizada na Estação Experimental do Instituto Agronômico do Paraná – IAPAR, em Pato Branco, Paraná. As parcelas principais tiveram como tratamento as plantas de cobertura: azevém (Lolium multiflorum L.), centeio (Secale cereale L.), ervilhaca comum (Vica sativa L.), ervilhaca peluda (Vicia villosa Roth) + aveia preta (Avena strigosa Schreb), nabo forrageiro (Raphanus sativus L.), pousio e trigo (Triticum aestivum L.), enquanto nas sub-parcelas foram utilizados dois sistemas de preparo do solo: SPD e SCC. As coletas ocorreram em três períodos distintos: pós-colheita do milho (safra 2014-2015), no florescimento das plantas de cobertura (2015) e no florescimento da soja (safra 2015-2016). A profundidade coletada foi de 0 a 0,10 m. A análise química das diferentes frações de P foi realizada com os seguintes métodos: P potencialmente disponível, por Mehlich 1 e resina trocadora de ânions (RTA); P armazenado na Biomassa Microbiana do Solo (BMS), através da fumigação com clorofórmio; P moderadamente lábil, pelo extrator NaOH 0,5 mol l˗1, P orgânico total (Po Total), pela ignição a 550°C em mufla e posterior extração com ácido sulfúrico; P total (P Total), pelo método de digestão em bloco; P inorgânico total (Pi Total), pela diferença entre o P Total e Po Total. Quando comparado ao SCC, o SPD apresentou as maiores médias de P extraído em todas frações analisadas. As parcelas cultivadas com trigo tiveram as menores médias de P disponível por Mehlich (7,9 mg kg˗1) e de P estocado na BMS (30,8 mg kg˗1). O P orgânico (Po), tanto no SCC quanto no SPD, correspondeu a 30% do P total. Concluiu-se que, o cultivo do solo sem revolvimento, com plantas hibernais e com altas produtividades do solo, parte do P inorgânico aplicado se acumula em formas orgânicas moderadamente lábeis.

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Gubiani, Elci. "Estoque de carbono e nitrogênio em solo sob sistemas de manejo e culturas de inverno." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/5616.

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Soil organic matter (SOM) constitutes the largest reservoir of carbon (C) and nitrogen (N) of the earth's surface. In agricultural soils, the organic fraction is of great importance in maintaining soil quality, while contributing a small fraction. Thus, the adoption of soil management practices and cover crops are important to promote th e C and N accumulation in the soil and consequently improve its quality. The no - tillage system (NT ) as conservation practice improves the soil structure, water infiltration and increases the contribution of C and N in the soil by deposition of crop residue on the surface. Thus, the soil is kept constantly covered by organic residuce of plants during their vegetative stage. This study aims to evaluate the stocks of C and N in the profile of a very clayey soil . The winter cover crops were grown under two mana gement systems i. e., NT and conventional - tillage system (CT ) in an long - term 26 years experiment. The experiment was started in the winter of 1986 in an Oxisol rich in aluminium , in southwestern Paraná at the Agronomic Institute of Paraná, with eight winter treatments (oat, rye, vetch , hairy vetch, wild radish, wheat, blue lupine and fallow). The collection of the soil samples was conducted in November 2012 at the following depths: 0 5, 5 10, 10 20, 20 30, 30 40, 40 60, 60 80 and 80 100 cm. A soil samples were collected under native forest from an area adjacent the experimental area serving as control . The soil C and N contents through the elemental analyzer. After 26 years of cultivation, the soil under NT showed the highest levels and stocks of C and N in the surface layers compared to the CT . However, b elow 20 cm and even upto 1 meter de p th , the soil C and N stocks did not differ between the soil management systems. Regarding the use of different plant cover, these treatments did not differ in stocks of C and N in both management systems (NT and CT). A matéria orgânica do solo (MOS) constitui o maior reservatório de carbono (C) e nitrogênio (N) da superfície terrestre. Em solos agrícolas, a fração orgânica tem grande importância na manutenção da qualidade do solo, apesar de contribuir com uma pequena fração. Dessa forma, a adoção de práticas de manejo de solo e plantas de cobertura é importante para promover o acúmulo de C e N no solo e, consequentemente, a melhoria de sua qualidade. O sistema plantio direto (SPD), como prática conservacionista, melhora a estrutura, a infiltração de água no solo e aumenta o aporte de C e N no solo, através da deposição dos resíduos culturais em sua superfície. Assim, o solo é mantido permanentemente coberto por resíduos orgânicos culturais ou pelas plantas em fase vegetativa. O presente trabalho tem como objetivo avaliar os estoques de C e N no perfil de um solo muito argiloso em que foram cultivadas plantas de cobertura de inverno sob dois sistemas de manejo (SPD e sistema cultivo convencional (SCC)), em um experimento de longa duração (26 anos). O experimento foi instalado no inverno de 1986, em um Latossolo Vermelho Aluminoférrico, na região sudoeste do Paraná, no Instituto Agronômico do Paraná, com dois sistemas de manejo, SPD e SCC e com oito tratamentos de inverno (aveia preta, centeio, ervilhaca comum, ervilhaca peluda, nabo forrageiro, trigo, tremoço azul e o pousio). A coleta das amostras de solo foi realizada em novembro de 2012, nas seguintes profundidades: 0 5, 5 10, 10 20, 20 30, 30 40, 40 60, 60 80 e 80 100 cm. Também foram coletadas amostras de solo sob mata nativa, em área contígua à área experimental. Foram determinados os teores de C e N através do analisador elementar. Após 26 anos de cultivo, o solo sob SPD apresentou os maiores teores e estoques de C e N nas camadas superficiais comparativamente com o SCC. Abaixo de 20 cm e até a camada de um metro de profundidade, os estoques de C e N não diferiram entre os sistemas de manejo de solo. Quanto ao uso das diferentes plantas de cobertura, esses tratamentos não apresentaram diferenças nos estoques de C e N em ambos os sistemas de manejo (SPD e SCC).

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Munda, Bruce, Tim C. Knowles, Art Meen, Vic Wakimoto, and Bill Worthy. "Winter Forage Cover Crop Trials." College of Agriculture, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/208283.

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Several crops were evaluated at Worthy farms, near Marana, AZ, Wakimoto farms, Mohave Valley, near Bullhead City, AZ, and the Tucson Plant Materials Center for use as a winter cover crop following cotton with potential to reduce wind erosion and produce one to two hay cuttings. Hairy vetch (Vicia villosa), 'Lana' woolypod vetch (Vicia villosa ssp. varia), 'Papago' pea (Pisum sativum), and 'Biomaster' pea (Pisum sativum) were sown at the Tucson Plant Materials Center. Species sown at Worthy farm were: Papago pea, Lana vetch, and Biomaster pea. Species sown at Wakimoto farm were: Biomaster pea, Lana vetch, 'Seco' barley (Hordeum vulgare), and 'Multi-cut' berseem clover (Trifolium alexandrinum). Forage yield varied between locations due to sowning date, number of irrigations, and soil textures. Biomaster pea, Papago pea, and Lana vetch performed well at all three locations. However, Biomaster yields were more consistent and due to its shorter growing season may be the better choice as a winter cover between cotton crops. Additional trials are scheduled for the fall of 1998.

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Madafiglio, Gregory Peter. "Population management of Raphanus raphanistrum L. (wild radish) by regulating seed production." Thesis, View thesis View thesis, 2002. http://handle.uws.edu.au:8081/1959.7/339.

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Raphanus raphanistrum L. (wild radish) is a widespread and economically problematic weed of winter crops including wheat (Triticum aestivum L.) in southern Australia. Management of the weed is achieved by a range of non-chemical and chemical techniques. Current management is failing to contain the weed, which is increasing in abundance and distribution. The characteristics of staggered recruitment, dormancy, rapid growth, competitive ability and high levels of seed production contribute to its persistence. The literature review concludes that weeds formed the basis for perpetuation of R. raphanistrum, a claim further investigated by simulation modeling. The effective management of R. raphanistrum should aim to achieve declining populations and this requires the integration of all factors that regulate seed production. Reducing seed production of R. raphanistrum in wheat can be achieved by applying herbicides at reproductive stages of development. This technique has been demonstrated to be an effective, safe and practical method of reducing seed production of R. raphanistrum in wheat. Reducing seed production of R. raphanistrum by herbicides applied at reproductive stages of development is a technique that can be incorporated into an integrated weed management program to improve control

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Wang, Guangyao (Sam), William McCloskey, Mike Foster, and David Dierig. "Lesquerella: A Winter Oilseed Crop for the Southwest." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/147025.

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4 pp. Lesquerella (Lesquerella fendleri) is a member of the mustard family and is native to the southwestern United States and northern Mexico. The oil in lesquerella seeds has superior performance compared to castor, soybean, and rapeseed methyl esters in reducing wear and damage in fuel injected diesel engines. Lesquerella can also be used as an ingredient for a number of other bioproducts such as lubricants, motor oils, plastics, inks, and adhesives. The hydroxylated oil in lesquerella is similar to castor oil but does not contain the deadly poison ricin. Therefore, lesquerella is a safer alternative to castor in the United States and can be handled both at the farm level and the oilseed processing level with industry standard equipment and technology. This article provide information to growers in planting, water and nutrient management, pest management, and harvesting of lesquerella as a potential alternative crop.

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Murphy, Donal Patrick Lee. "Crop structure and crop productivity in winter barley, (Hordeum sativum)." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262202.

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Wiesehoff, Marcel. "Teilflächenspezifische Aussaat von Winterweizen /." Hohenheim : Universität Hohenheim, Institut für Agrartechnik, Verfahrenstechnik in der Pflanzenproduktion, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015489100&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Nolte, Kurt, Mike Ottman, Trent Teegerstrom, and Guangyao (Sam) Wang. "Minimum tillage for wheat following winter vegetables." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/146999.

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4 pp. Wheat Production on Lettuce Beds In 2009, over 56,000 acres were planted to wheat in Arizona, all of which following either a lettuce or cotton crop. For wheat grown in the region, the conventional tillage sequence prior to planting can be tied to as many as seven field operations that consume valuable time, labor, and resources. In this study, our aim was to determine the effectiveness of reducing the number tillage (minimum till) operations in fields immediately following lettuce harvest. And demonstrate to Southwest wheat producers a means for conserving time, fuel, and resources. Growing wheat on lettuce beds immediately following lettuce harvest did not significantly reduce grain yield or quality. Although the regrowth of the previous crop can have significant implications for Durum grown with minimum tillage if not managed effectively, lodging was not a significant factor in this study as the degree of lodging was similar in both growing systems. The significant savings in fuel, labor and time, with no apparent reduction in Durum yield or quality, may be a significant benefit to wheat producers who incorporate minimum tillage practices following a lettuce crop.

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Kermode, G. N. "Autumn control of broad-leaved weeds in winter barley." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381921.

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Jenkinson, Peter. "Epidemiology of Fusarium in winter wheat (Triticum aestivum L.)." Thesis, Open University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386201.

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