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Letteratura scientifica selezionata sul tema "Wheat Yield"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 31 gennaio 2023

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Articoli di riviste sul tema "Wheat Yield"

1

Asthir, Bavita, Shashi Bala e Navtej Singh Bains. "Effect of Terminal Heat Stress on Yield and Yield Attributes of Wheat". Indian Journal of Applied Research 4, n. 6 (1 ottobre 2011): 1–2. http://dx.doi.org/10.15373/2249555x/june2014/1.

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2

Altay, F., e N. Bolat. "Effect of soilborne wheat mosaic virus on winter wheat yield and yield components". Acta Agronomica Hungarica 52, n. 3 (1 novembre 2004): 309–17. http://dx.doi.org/10.1556/aagr.52.2004.3.12.

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Soil-borne wheat mosaic virus (SBWMV) is an important disease of wheat production areas throughout the world, causing a great reduction in wheat and barley yields. The most effective way of controlling the disease is the use of resistant varieties in infested areas. In this study, the effects of SBWMV on yields and some yield components of eight susceptible, one moderately susceptible/resistant and nine resistant varieties were evaluated using data from 9 virus-infested and 6 non-infested sites in Eskisehir, Turkey over 6 years. The susceptible varieties yielded 5.35% more than resistant varieties in non-infested sites, while they gave 28.98% lower yield in infested sites. Significant yield loss differences were observed between the varieties in infested sites. Decreases were also observed in yield components at various levels. This study showed that SBWMV is an important disease, which survives in soil for long periods and causes significant yield decreases in wheat. Recently developed varieties have good resistance to the disease and are recommended to farmers in infested areas. Abbreviations: SBWMV, soil-borne wheat mosaic virus

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3

Jan, Křen, Houšť Martin, Tvarůžek Ludvík e Jergl Zdeněk. "Are intensification and winter wheat yield increase efficient?" Plant, Soil and Environment 63, No. 9 (26 settembre 2017): 428–34. http://dx.doi.org/10.17221/482/2017-pse.

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The results of small-plot field trials of international comparisons of a series of crop management practices for winter wheat grown during 2014–2016 on fertile soils of Central Moravia were assessed. The objective of the experiments was to obtain the highest gross margin (GM), which is the difference between revenues and direct costs. The analyses showed that an optimal level of inputs and costs for obtaining the highest GM could exist. In the assessed series of crop management practices, the optimum input costs corresponded to 11 000–12 000 CZK/ha and 6–9 input measures. At high levels of grains (above 10 t/ha), higher values of GM were obtained by increased efficiency of inputs, but not by increasing their amount to maximize the yields. This indicates the multifunctional and synergic effects of production factors, which can be used at the so-called ecological intensification. Optimizations of inputs can be obtained rather by crop protection than by crop nutrition, which means rather in protection of high yields than in their maximization. Under field conditions, soil and plant processes affected by weather cannot be controlled. Therefore, optimisation of production factors is based both on scientific findings and practical agronomic experience. That is why a universal crop management practice with increased economic and ecological effects cannot be practically proposed.

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4

Lin, M., e P. Huybers. "Reckoning wheat yield trends". Environmental Research Letters 7, n. 2 (16 maggio 2012): 024016. http://dx.doi.org/10.1088/1748-9326/7/2/024016.

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5

Bahrani, M. J., M. Kheradnam, Y. Emam, H. Ghadiri e M. T. Assad. "EFFECTS OF TILLAGE METHODS ON WHEAT YIELD AND YIELD COMPONENTS IN CONTINUOUS WHEAT CROPPING". Experimental Agriculture 38, n. 4 (20 agosto 2002): 389–95. http://dx.doi.org/10.1017/s001447970200042x.

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A three-year field experiment was undertaken to evaluate the effects of tillage methods on grain yield and yield components of wheat (Triticum aestivum) in continuous cropping. The experiment was conducted on a Ramjerd, fine, mixed, mesic, typic Calcixerepts soil. Wheat was sown: (1) after burning residues followed by conventional tillage, (2) after complete residue removal followed by conventional tillage, (3) after soil incorporation of residues followed by conventional tillage, (4) into untilled residues, (5) using chisel seeder after field irrigation, (6) using chisel seeder plus herbicide application, and (7) after disking. Residue burning and removal increased spikes per square metre, grain per spike, 1000-grain weight, grain yield and harvest index compared with other treatments. This was due primarily to weed interference and lack of uniform crop establishment in the presence of residues. Reduced tillage methods retained more residues on the soil surface, which provided unsuitable conditions for crop emergence and growth. The incorporation of residues led to a build up of carbon in the soil, with lower grain yields compared with residue burning and removal, but these yields were higher than those of chisel-seeded plots.

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6

Sweeney, G., RS Jessop e H. Harris. "Yield and yield structure of triticales compared with wheat in northern New South Wales". Australian Journal of Experimental Agriculture 32, n. 4 (1992): 447. http://dx.doi.org/10.1071/ea9920447.

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The yields and yield structure of cultivars of triticales and bread wheats (with a range of phasic development patterns in both species) were compared in 2 field experiments at Narrabri in northern New South Wales. The experiments were performed on a grey cracking clay soil with irrigation to prevent severe moisture stress. Triticales, both early and midseason types, appeared to have reached yield parity with well-adapted wheat varieties. Meaned over the 2 experiments and all sowings, the triticales yields were 19% greater than the bread wheats. Triticales were generally superior to wheat in all components of yield of the spike (1000-grain weight, grain number/spikelet and spikelet number/spike), whilst the wheats produced more spikes per unit area. The triticales also had higher harvest indices than the wheats. The results are discussed in relation to the overall adaptability of triticale for Australian conditions.

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7

Budzyński, W. S., K. Bepirszcz, K. J. Jankowski, B. Dubis, A. Hłasko-Nasalska, M. M. Sokólski, J. Olszewski e D. Załuski. "The responses of winter cultivars of common wheat, durum wheat and spelt to agronomic factors". Journal of Agricultural Science 156, n. 10 (dicembre 2018): 1163–74. http://dx.doi.org/10.1017/s0021859619000054.

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AbstractA field experiment with the 35–1 fractional factorial design and five factors (k = 5) at three levels (s = 3) was performed in 2007–2010 at the Agricultural Experiment Station in Bałcyny, north-eastern (NE) Poland. The results of the experiment carried out under the agro-ecological conditions of NE Poland confirmed the high yield potential of common wheat and satisfactory yield potential of spelt and durum wheat. On average, durum wheat and spelt yields were 2.14 and 2.55 t/ha lower, respectively, than common wheat yields. Sowing date was not correlated with the yields of analysed Triticum species. Seed rate (350, 450 and 550 seeds/m2) had no significant influence on the grain yield of winter cultivars of common wheat, durum wheat and spelt. Common wheat cv. Oliwin and durum wheat cv. Komnata were characterized by the highest yields in response to nitrogen (N) fertilizer rates calculated based on the Nmin content of soil. An increase in the spring fertilizer rate by 40 kg N/ha in excess of the balanced N rate was not justified because it did not induce a further increase in the grain yield of common wheat and durum wheat. The grain yield of spelt cv. Schwabenkorn continued to increase in response to the highest rate of N fertilizer in spring (40 kg N/ha higher than the optimal rate). Intensified fungicide treatments improved grain yield in all Triticum species.

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8

Hnilička, F., J. Petr, H. Hniličková e J. Martinková. "The yield formation in the alternative varieties of wheat". Czech Journal of Genetics and Plant Breeding 41, Special Issue (31 luglio 2012): 295–301. http://dx.doi.org/10.17221/6197-cjgpb.

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9

Waines, J. G., e B. Ehdaie. "Breeding for root characters and grain yield in wheat". Czech Journal of Genetics and Plant Breeding 41, Special Issue (31 luglio 2012): 326–30. http://dx.doi.org/10.17221/6212-cjgpb.

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10

Akcura, M., Y. Kaya, S. Taner e R. Ayranci. "Parametric stability analyses for grain yield of durum wheat". Plant, Soil and Environment 52, No. 6 (17 novembre 2011): 254–61. http://dx.doi.org/10.17221/3438-pse.

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Grain yield of 15 durum wheat (Triticum durum Desf.) genotypes consisting of 13 cultivars and 2 advanced lines, tested in a randomized complete block design with four replications across 8 environments of Central Anatolian Region of Turkey was analyzed using nine parametric stability measures. The objectives were to assess genotype-environment interactions (GEI), determine stable genotypes, and compare mean grain yield with the parametric stability parameters. To quantify yield stability, nine stability statistics were calculated (b<sub>i</sub>, S<sup>2</sup><sub>di</sub>, R<sub>i</sub><sup>2</sup>, W <sub>i</sub><sup>2</sup>, σ<sub>i</sub><sup>2</sup>, S<sup>2</sup><sub>i</sub>, α<sub>i</sub> and λ<sub>i</sub>). Yilmaz-98, Cakmak-79, Kiziltan-91, Selcuklu-97 and C-1252 were more stable cultivars, which had 9, 8, 6, 6, 6 out of all 9 stability statistics used, respectively. Especially, among these cultivars, Yilmaz-98 and Cakmak-79 were the most stable cultivars. Furthermore, three-dimensional plots of mean response versus each stability statistic were shown to visually evaluate the yield potential and stability estimates of the genotypes. Genotype mean yield (–x) was significantly positively correlated to the regression coefficient (b<sub>i</sub>), environmental variance and genotype to the environmental effects (α<sub>i</sub>), indicating that high grain yielding genotypes had larger values b<sub>i</sub>, S<sup>2</sup><sub>i</sub>, and α<sub>i</sub>, S<sup>2</sup><sub>i</sub>, W <sub>i</sub><sup>2</sup>, CV<sub>i</sub>, α<sub>i</sub> and b<sub>i</sub>, were significantly correlated, indicating that they measured similar aspects of stability

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Tesi sul tema "Wheat Yield"

1

Dick, G., J. Harper, L. Moore e M. Ottman. "Effect of Russian Wheat Aphid on Durum Wheat Yield". College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/200817.

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2

Zubaidi, Akhmad. "Growth and yield of durum and bread wheat". Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09A/09az93.pdf.

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Bibliography: leaves 148-160. A series of experiments was conducted to examine the growth and nutrient uptake of durum and bread wheat at a number of sites in South Australia. The experiments examined response to water stress, the pattern of root and shoot growth, soil water extraction and nutrient uptake among a range of adapted bread wheat and durum wheat cultivars.

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3

Husaker, Douglas, e Dale Bucks. "Crop Yield Variability in Irrigated Wheat". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/200484.

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Optimum design and management of irrigated wheat production is limited by the scarcity of information available on yield variability. The purpose of this study was to evaluate the spatial variability in soil-water parameters and the effects compared to grain yield response under level-basin irrigation. Three levels of seasonal irrigation water and two border lengths were used. Grain yields were found to increase significantly with the amount of water applied and soil water depletion (estimate of crop evapotranspiration), although yield variability was greater with reduced or deficit irrigations. Variations in soil water content were responsible for about 22% of the variability in grain yield, indicating that other soil and crop- related factors had a significant influence on production. Spatial dependence was exhibited over a greater distance at the wetter compared with the drier irrigation regimes.

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4

Torofder, Golam. "Manipulating wheat yield in semi-arid environments". Thesis, University of Aberdeen, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394451.

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Findings from a number of recent glasshouse studies are reported and their relevance to wheat production practices in Bangladesh is discussed. It was found that application of large amounts of urea gave highest grain yield when the total amount of urea was added immediately after irrigation following germination. The same amount of urea applied before irrigation or in smaller doses throughout the growing season gave lower yield and resulted in higher post-harvest concentrations of soil nitrate. Reducing the total urea application to one quarter of the typical maximum reported value, did not cause a reduction in yield and this could be achieved with only one occasion of irrigation (as opposed to two) following germination. The findings confirm the recommended dosage of urea (typically 250 kg urea ha^-1) and indicate the importance of applying urea after irrigation to maximise yield and minimise post-harvest soil nitrate concentrations. Adding a nitrate fertiliser as opposed to the same amount of urea-N did not result in a significant yield increase. The results indicate that application of urea-N following irrigation results in a rapid availability of soil N for plant uptake. Where severe soil drying occurs in the upper rooting zone, grain field was drastically reduced. This occurred even where longer roots had access to non-limiting amounts of water and nutrients. It was found that roots in the drying soil produced the plant hormone abscisic acid (ABA) and that this had a likely causal significance in decreasing yield. ABA was also produced in plants with ammonium- as opposed to nitrate nutrition and this was also associated with reduced yield. It was concluded that breeding for deep rooting alone would be insufficient to attain high yield if the upper part of root system was exposed to severe soil water deficit. Breeding of deep rooting in combination with a decreased sensitivity of stomatal closure to ABA, is an attractive possibility for plant and yield improvement for semi-arid zones. In the interim, current measures of tillage and mulching that enhance the water content of the upper rooting zone should be encouraged. Such measures are likely to counter the potential ABA-induced inhibition of yield associated with partial root dehydration and incomplete nitrification of soil ammonium.

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Misailidis, Nikiforos. "Understanding and predicting alcohol yield from wheat". Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/understanding-and-predicting-alcohol-yield-from-wheat(845cbadd-5825-488e-94e7-160c60b2ef0d).html.

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Bioethanol is a promising renewable biofuel and wheat is currently the main candidate asthe feedstock for its production in the UK context. The quality of the numerous varieties ofwheat developed in the past by plant breeders has been well examined in terms of bread, biscuitand pasta producing industries. In general, the end-use quality determination of wheat in termsof alcohol yield is less investigated. This work focused on understanding and predicting thealcohol yield from wheat according to its physical, physicochemical and chemicalcharacteristics. The research ran alongside the GREEN Grain project and utilised its wheatsamples, which consist of a range of wheat varieties, agronomic regimes and growing sitesfrom four harvests years 2005-2008. The combined dataset consists of a diverse range ofchemical, physicochemical and physical characteristics of the GREEN Grain wheats. An initial multivariate analysis (PCA) indicated that the first principal component, whichexplains most of the variability of the wheat characteristics, is related with the classification ofwheat as hard or soft. High alcohol yielding wheats typically have high starch, mealiness andalbumin+globulin fraction, and also low protein, gliadin fraction and hardness. They also havelarger and more spherical kernels. Analysis of Variance (ANOVA) was applied in order to identify differences between thevarieties, the sites and the application or not of N fertiliser. The ANOVA showed that theapplication of N fertiliser increases all the protein components, although it increases the Gliadinand the LMW glutenins more. N fertiliser also yields smaller (TGW, width, depth) and moreelongated kernels. High alcohol yielding varieties tend to be softer with lower protein andlarger and more spherical kernels. This consistent variability allowed prediction of the alcoholyield based on easily measured parameters. The following model, based on the SKCS reportedvalues plus protein, could predict the alcohol yield with an R2 of about 78%:Alcohol yield = 466.62 - 5.07 × Protein - 0.21 × hardness + 11.6 × diameter ±6.94 l/dry tonIt is frequently hypothesised that larger and more rounded kernels produce more alcoholbecause they have a smaller relative amount of the unfermentable outer layers. In an effort totest this hypothesis, the pericarp thicknesses and the crease characteristics of the wheat sampleswere measured. It was found that pericarp thickness and crease dimensions vary with kernelsize, with significant differences between varieties. A physical model was developed thatconsiders these differences and calculates the endosperm to non-endosperm ratio. None of thevariables obtained by the physical model could be related to alcohol yield. The SKCS fundamental data were further analysed in an effort to improve the alcoholyield predictability. It was found that the averaged Crush Response Profiles are morereproducible than the hardness index itself. It was shown that the initial peak does not occurbecause of the "shell" (i.e. the bran layers) as suggested in the literature, but because of thecrease. Examination of the effects of moisture content on the aCRPs showed that their 1stquarter is equivalent to the stress-strain plots of dedicated rheological tests. The remaining partsof the curve relate to the post-failure behaviour of the kernels and with hardness as used incereal science. The aCRP parameters could improve the alcohol yield predictability of theGREEN Grain wheats to an R2 of about 82.3% and a standard error of the regression of6.3 l/dry ton. Further standardisation and calibration with respect to the moisture content and tothe size of the kernels could improve the predictions even further. Textural testing of cereals is constrained by the complexity of the wheat kernel structureand exacerbated by the between-kernel variation. The current work has demonstrated howSKCS data can be interpreted more insightfully in order to improve end-use quality predictions. The aCRP parameters clearly contain rheological information about wheats. Further research toestablish their examination by more standardised methodologies will allow effectiveinvestigation of connections between the rheological properties, chemical characteristics,processing behaviour and end-use quality prediction of wheat.

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Farr, Chuck. "Yield Requirements of Non-Premium Durum Wheat". College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/200542.

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7

Grotenhuis, Timothy P. "Superoptimal CO2 Reduces Seed Yield in Wheat". DigitalCommons@USU, 1996. https://digitalcommons.usu.edu/etd/6747.

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Although projected terrestrial CO2 levels will not reach 1000 μmol moI-1 (0.1%) for many decades, CO2 levels in growth chambers and greenhouses routinely exceed that concentration. CO2 levels in life support systems in space can exceed 10,000 μmol moI-1 (1%) CO2. Numerous studies have examined CO2 effects up to 1000 μmol mol-1, but theoretical and some experimental evidence indicates that the beneficial effects of CO2 continue past 1000 μmol mol-1 and are near-optimal for wheat at about 1200 μmol mol-1. We studied the effects of near-optimal and superoptimal CO2 levels (>1200 μmol mol-1) on yield of two cultivars of hydroponically grown wheat in 12 trials. Increasing CO2 from suboptimal to near-optimal (350 to 1200 μmol mol-1) increased vegetative growth by 25% and seed yield by 15% in both cultivars. Yield increases were primarily the result of an increased number of heads m-2. Further elevation of CO2 to 2500 μmol mol-1reduced seed yield by 22% in cv. 'Veery-10' and by 15% in cv. 'USU-Apogee'. Superoptimal CO2 did not decrease the number of heads m-2, but reduced seeds per head by 10% and mass per seed by 11%. CO2 toxicity occurred over a wide range of light levels. Subsequent trials revealed that superoptimal CO2 in the 2 weeks before and after anthesis mimicked the effect of constant superoptimal CO2. Furthermore, near-optimal CO2 in the 2 weeks before and after anthesis mimicked the effect of constant near-optimal CO2. Nutrient concentration of leaves and heads was not affected by CO2. The yield decreases may be a response mediated by ethylene.

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8

Ottman, Michael J. "Wheat and barley varieties for Arizona, 2017". College of Agriculture, University of Arizona (Tucson, AZ), 2017. http://hdl.handle.net/10150/625860.

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Ottman, Michael J. "Wheat and barley varieties for Arizona, 2016". College of Agriculture, University of Arizona (Tucson, AZ), 2016. http://hdl.handle.net/10150/625421.

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Sloane, David. "Early vigour : its role in enhancing the productivity of wheat grown in South Australia /". Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09AFP/09afps634.pdf.

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Libri sul tema "Wheat Yield"

1

AGRICULTURE, US DEPARTMENT OF. 2004 wheat objective yield survey interviewer's manual. Washington, D.C: U.S. Dept. of Agriculture, National Agricultural Statistics Service, Agricultural Statistics Board, 2004.

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AGRICULTURE, US DEPARTMENT OF. 2001 wheat objective yield survey interviewer's manual. [Washington, D.C.?: U.S. Dept. of Agriculture, 2001.

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3

Davies, Samuel. Soybean and wheat crops: Growth, fertilization, and yield. Hauppauge, NY: Nova Science Publishers, 2009.

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H, Satorre Emilio, e Slafer Gustavo A. 1960-, a cura di. Wheat: Ecology and physiology of yield determination. New York: Food Products Press, 1999.

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Smith, Edward L., a cura di. Genetic Improvement in Yield of Wheat. Madison, WI, USA: Crop Science Society of America and American Society of Agronomy, 1986. http://dx.doi.org/10.2135/cssaspecpub13.

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Braun, H. J., M. P. Reynolds e J. Pietragalla. International symposium on wheat yield potential: Challenges to international wheat breeding. A cura di International Maize and Wheat Improvement Center. Mexico: CIMMYT, 2008.

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Smiley, Richard W. Plant-parasitic nematodes affecting wheat yield in the Pacific Northwest. [Corvallis, Or.]: Oregon State University Extension Service, 2005.

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Smiley, Richard W. Plant-parasitic nematodes affecting wheat yield in the Pacific Northwest. [Corvallis, Or.]: Oregon State University Extension Service, 2005.

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Dumanski, J. Identification of crop production risk areas in Manitoba based on agroecological resources. [Ottawa]: Research Branch, Agriculture Canada, 1992.

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Teigen, Lloyd D. Weather and yield, 1950-94: Relationships, distributions, and data. [Washington, DC]: Economic Research Service, Commercial Agriculture Division, 1995.

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Capitoli di libri sul tema "Wheat Yield"

1

Westcott, B. "Yield assessment". In Wheat Breeding, 339–68. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3131-2_12.

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Foulkes, M. John, Gemma Molero, Simon Griffiths, Gustavo A. Slafer e Matthew P. Reynolds. "Yield Potential". In Wheat Improvement, 379–96. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_21.

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AbstractThis chapter provides an analysis of the processes determining the yield potential of wheat crops. The structure and function of the wheat crop will be presented and the influence of the environment and genetics on crop growth and development will be examined. Plant breeding strategies for raising yield potential will be described, with particular emphasis on factors controlling photosynthetic capacity and grain sink strength.

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Richards, Richard A. "Drought". In Wheat Improvement, 417–32. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_23.

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AbstractEstablished breeding methods for wheat in dry environments continue to make gains. It will remain the cornerstone for wheat improvement. This Chapter discusses proven methods to make additional gains. It discusses a way to benchmark yield potential in dry environments and how this can be used to determine whether unexpected agronomic or genetic factors are limiting yields. It examines opportunities, advantages and disadvantages of trait-based selection methods for dry environments, and it presents a framework by which important traits can be selected. Both high throughput and marker-based methods of selection are examined for their success and feasibility of use in breeding. It also highlights the importance of agronomic approaches in combination with breeding to continue to improve yield potential in water limited environments. Finally, the elements of success of translation from research to the delivery of new varieties is examined.

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4

Graybosch, Robert, Harold E. Bockelman, Kimberly A. Garland-Campbell, David F. Garvin e Teshome Regassa. "Wheat". In Yield Gains in Major U.S. Field Crops, 459–87. Madison, WI, USA: American Society of Agronomy and Soil Science Society of America, 2015. http://dx.doi.org/10.2135/cssaspecpub33.c16.

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5

Pfeiffer, W. H., K. D. Sayre, M. P. Reynolds e T. S. Payne. "Increasing Yield Potential and Yield Stability in Durum Wheat". In Wheat in a Global Environment, 569–77. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-017-3674-9_76.

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Johnson, V. A. "World Wheat Production". In Genetic Improvement in Yield of Wheat, 1–5. Madison, WI, USA: Crop Science Society of America and American Society of Agronomy, 2015. http://dx.doi.org/10.2135/cssaspecpub13.c1.

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7

Hay, R. K. M. "Physiological Control of Growth and Yield in Wheat: Analysis and Synthesis". In Crop Yield, 1–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-642-58554-8_1.

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Bharadiya, Nitin, e Vivek Manekar. "Agrometeorological Wheat Yield Prediction Models". In Water Science and Technology Library, 285–92. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-55125-8_24.

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9

Singh, Ravi P., Philomin Juliana, Julio Huerta-Espino, Velu Govindan, Leonardo A. Crespo-Herrera, Suchismita Mondal, Sridhar Bhavani et al. "Achieving Genetic Gains in Practice". In Wheat Improvement, 97–123. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_7.

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AbstractAccelerating the rate of genetic gain for grain yield together with key traits is pivotal for delivering improved wheat varieties. The key strategies of CIMMYT’s spring bread wheat improvement program to continuously increase genetic gains and deliver elite wheat lines to national partners in the target countries include: breeding for product profiles that prioritize selection traits; robust choice of diverse parents by leveraging all phenotypic and genotypic data; effective crossing schemes with an optimal proportion of different types of crosses; early-generation advancement using the selected-bulk breeding scheme that reduces operational costs; the two generations/year field based “shuttle-breeding” that reduces the breeding cycle time while selecting breeding populations in contrasting environments with diverse biotic and abiotic stresses; making advancement decisions for elite lines using data from intensive multi-trait, multi-year and multi-environment phenotyping; integrating new methods like genomic selection; utilizing yield and phenotypic data from international yield trials and screening nurseries generated by worldwide partners for identifying and utilizing superior lines; and maintaining effective partnerships with the National Agricultural Research Systems who serve as key leaders in developing, releasing, and disseminating varieties to farmers. In addition to these strategies, new breeding schemes to reduce the cycle time and recycle parents in 2–3 years are being piloted and optimized to further accelerate genetic gain.

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Tony Fischer, R. A. "History of Wheat Breeding: A Personal View". In Wheat Improvement, 17–30. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_2.

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AbstractFor more than a century, breeding has delivered huge benefits as a major driver of increased wheat productivity and of stability in the face of inevitable disease threats. Thus, the real cost of this staple grain has been reduced for billions of consumers. Steady breeding progress has been seen across many important traits of wheat, currently for potential yield averaging about 0.6% p.a. This yield progress continues to rely of extensive multilocational yield testing but has, however, become more difficult, even as new breeding techniques have improved efficiency. Breeding will continue to evolve as new approaches, being proposed with increasing frequency, are tested and found useful or not. High throughput phenotyping (HTPP), applying modern crop physiology, and molecular markers and genomic selection (GS) are in this phase right now. Such new techniques, along with pre-breeding for new traits, will likely play a larger role in this future improvement of wheat. New tools will also include genetic engineering (GE), as society’s need for its benefits become more urgent. The steady privatization of breeding seems unlikely to cease in the developed world but will continue to struggle elsewhere. It would seem wise, however, that a significant portion of the world’s pre-breeding research remains in the public sector, while maintaining close and equitable contact with those delivering new varieties.

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Atti di convegni sul tema "Wheat Yield"

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Fajardo, M., B. Whelan, P. Filippi e T. Bishop. "Wheat yield forecast using contextual spatial information". In 12th European Conference on Precision Agriculture. The Netherlands: Wageningen Academic Publishers, 2019. http://dx.doi.org/10.3920/978-90-8686-888-9_88.

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Lamba, Vikas, Susheela Hooda, Rakesh Ahuja e Amandeep Kaur. "Wheat Yield Prediction Using Feedforward Neural Networks". In 2021 9th International Conference on Reliability, Infocom Technologies and Optimization (Trends and Future Directions) (ICRITO). IEEE, 2021. http://dx.doi.org/10.1109/icrito51393.2021.9596464.

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Skakun, S., B. Franch, J. C. Roger, E. Vermote, I. Becker-Reshef, C. Justice e A. Santamaria-Artigas. "Incorporating yearly derived winter wheat maps into winter wheat yield forecasting model". In IGARSS 2016 - 2016 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2016. http://dx.doi.org/10.1109/igarss.2016.7730869.

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Kadir, Muhd Khairulzaman Abdul, Mohd Zaki Ayob e Nadaraj Miniappan. "Wheat yield prediction: Artificial neural network based approach". In 2014 4th International Conference on Engineering Technology and Technopreneuship (ICE2T). IEEE, 2014. http://dx.doi.org/10.1109/ice2t.2014.7006239.

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Moiseeva, Ksenia, Alexander Karmatskiy e Anastasia Moiseeva. "Influence of Mineral Fertilizers on Winter Wheat Yield". In International scientific and practical conference "AgroSMART - Smart solutions for agriculture" (AgroSMART 2018). Paris, France: Atlantis Press, 2018. http://dx.doi.org/10.2991/agrosmart-18.2018.94.

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"Wheat Yield Response to Limited Irrigation and Fungicides". In 2015 ASABE International Meeting. American Society of Agricultural and Biological Engineers, 2015. http://dx.doi.org/10.13031/aim.20152190459.

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Mikos-Szymańska, Marzena, Mieczysław Borowik, Marta Wyzińska e Piotr Rusek. "Effects of different fertilizer treatments on grain yield and yield components of spring wheat". In Research for Rural Development, 2018. Latvia University of Life Sciences and Technologies, 2018. http://dx.doi.org/10.22616/rrd.24.2018.058.

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Dai, Cheng, Yinqin Huang, Minghao Ni e Xingang Liu. "Wheat Yield Forecasting using Regression Algorithms and Neural Network". In 2020 International Conferences on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData) and IEEE Congress on Cybermatics (Cybermatics). IEEE, 2020. http://dx.doi.org/10.1109/ithings-greencom-cpscom-smartdata-cybermatics50389.2020.00038.

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Yanwei Yuan e (or initial) (or initial). "Collect and Analyze the Distributing Information of Wheat Yield". In 2007 Minneapolis, Minnesota, June 17-20, 2007. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2007. http://dx.doi.org/10.13031/2013.23363.

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Zhang, Yao, e Qiming Qin. "Winter Wheat Yield Estimation with Ground Based Spectral Information". In IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2018. http://dx.doi.org/10.1109/igarss.2018.8519582.

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Rapporti di organizzazioni sul tema "Wheat Yield"

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Petzold, Christopher, Ai Oikawa e Yang Tian. Fast growing high-yield wheat and canola for efficient nutrient recycling systems. Office of Scientific and Technical Information (OSTI), gennaio 2020. http://dx.doi.org/10.2172/1593301.

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Blum, Abraham, e Henry T. Nguyen. Molecular Tagging of Drought Resistance in Wheat: Osmotic Adjustment and Plant Productivity. United States Department of Agriculture, novembre 2002. http://dx.doi.org/10.32747/2002.7580672.bard.

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Drought stress is a major limitation to bread wheat (Triticumaestivum L.) productivity and its yield stability in arid and semi-arid regions of world including parts of Israel and the U.S. Currently, breeding for sustained yields under drought stress is totally dependent on the use of yield and several key physiological attributes as selection indices. The attempt to identify the optimal genotype by evaluating the phenotype is undermining progress in such breeding programs. Osmotic adjustment (OA) is an effective drought resistance mechanism in many crop plants. Evidence exists that there is a genetic variation for OA in wheat and that high OA capacity supports wheat yields under drought stress. The major objective of this research was to identify molecular markers (RFLPs, restriction fragment length polymorphisms; and AFLPs, amplified fragment length polymorph isms) linked to OA as a major attribute of drought resistance in wheat and thus to facilitate marker-assisted selection for drought resistance. We identified high and low OA lines of wheat and from their cross developed recombinant inbred lines (RILs) used in the molecular tagging of OA in relation to drought resistance in terms of plant production under stress. The significant positive co-segregation of OA, plant water status and yield under stress in this RIL population provided strong support for the important role of OA as a drought resistance mechanism sustaining wheat production under drought stress. This evidence was obtained in addition to the initial study of parental materials for constructing this RIL population, which also gave evidence for a strong correlation between OA and grain yield under stress. This research therefore provides conclusive evidence on the important role of OA in sustaining wheat yield under drought stress. The measurement of OA is difficult and the selection for drought resistance by the phenotypic expression of OA is practically impossible. This research provided information on the genetic basis of OA in wheat in relations to yield under stress. It provided the basic information to indicate that molecular marker assisted selection for OA in wheat is possible. The RIL population has been created by a cross between two agronomic spring wheat lines and the high OA recombinants in this population presented very high OA values, not commonly observed in wheat. These recombinants are therefore an immediate valuable genetic recourse for breeding well-adapted drought resistant wheat in Texas and Israel. We feel that this work taken as a whole eliminate the few previous speculated . doubts about the practical role of OA as an important mechanism of drought resistance in economic crop plants. As such it should open the way, in terms of both concept and the use of marker assisted selection, for improving drought resistance in wheat by deploying high osmotic adjustment.

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Blum, Abraham, Henry T. Nguyen e N. Y. Klueva. The Genetics of Heat Shock Proteins in Wheat in Relation to Heat Tolerance and Yield. United States Department of Agriculture, agosto 1993. http://dx.doi.org/10.32747/1993.7568105.bard.

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Fifty six diverse spring wheat cultivars were evaluated for genetic variation and heritability for thermotolerance in terms of cell-membrane stability (CMS) and triphenyl tetrazolium chloride (TTC) reduction. The most divergent cultivars for thermotolerance (Danbata-tolerant and Nacozari-susceptible) were crossed to develop an F8 random onbred line (RIL) population. This population was evaluated for co-segragation in CMS, yield under heat stress and HSP accumulation. Further studies of thermotolerance in relations to HSP and the expression of heterosis for growth under heat stress were performed with F1 hybrids of wheat and their parental cultivars. CMS in 95 RILs ranged from 76.5% to 22.4% with 71.5% and 31.3% in Danbata and Nacozari, respectively. The population segregated with a normal distribution across the full range of the parental values. Yield and biomass under non-stress conditions during the normal winter season at Bet Dagan dit not differ between the two parental cultivar, but the range of segregation for these traits in 138 RILs was very high and distinctly transgressive with a CV of 35.3% and 42.4% among lines for biomass and yield, respectively. Mean biomass and yield of the population was reduced about twofold when grown under the hot summer conditions (irrigated) at Bet Dagan. Segregation for biomass and yield was decreased relative to the normal winter conditions with CV of 20.2% and 23.3% among lines for biomass and yield, respectively. However, contrary to non-stress conditions, the parental cultivars differed about twofold in biomass and yield under heat stress and the population segregated with normal distribution across the full range of this difference. CMS was highly and positively correlated across 79 RILs with biomass (r=0.62**) and yield (r=0.58**) under heat stress. No such correlation was obtained under the normal winter conditions. All RILs expressed a set of HSPs under heat shock (37oC for 2 h). No variation was detected among RILs in high molecular weight HSP isoforms and they were similar to the patterns of the parental cultivars. There was a surprisingly low variability in low molecular weight HSP isoforms. Only one low molecular weight and Nacozari-specific HSP isoform (belonging to HSP 16.9 family) appeared to segregate among all RILs, but it was not quantitatively correlated with any parameter of plant production under heat stress or with CMS in this population. It is concluded that this Danbata/Nacozari F8 RIL population co-segregated well for thermotolerance and yield under heat stress and that CMS could predict the relative productivity of lines under chronic heat stress. Regretfully this population did not express meaningful variability for HSP accumulation under heat shock and therefore no role could be seen for HSP in the heat tolerance of this population. In the study of seven F1 hybrids and their parent cultivars it was found that heterosis (superiority of the F1 over the best parent) for CMs was generally lower than that for growth under heat stress. Hybrids varied in the rate of heterosis for growth at normal (15o/25o) and at high (25o/35o) temperatures. In certain hybrids heterosis for growth significantly increased at high temperature as compared with normal temperature, suggesting temperature-dependent heterosis. Generally, under normal temperature, only limited qualitative variation was detected in the patterns of protein synthesis in four wheat hybrids and their parents. However, a singular protein (C47/5.88) was specifically expressed only in the most heterotic hybrid at normal temperature but not in its parent cultivars. Parental cultivars were significantly different in the sets of synthesized HSP at 37o. No qualitative changes in the patterns of protein expression under heat stress were correlated with heterosis. However, a quantitative increase in certain low molecular weight HSP (mainly H14/5.5 and H14.5.6, belonging to the HSP16.9 family) was positively associated with greater heterosis for growth at high temperature. None of these proteins were correlated with CMS across hybrids. These results support the concept of temperature-dependent heterosis for growth and a possible role for HSP 16.9 family in this respect. Finally, when all experiments are viewed together, it is encouraging to find that genetic variation in wheat yield under chronic heat stress is associated with and well predicted by CMS as an assay of thermotolerance. On the other hand the results for HSP are elusive. While very low genetic variation was expressed for HSP in the RIL population, a unique low molecular weight HSP (of the HSP 16.9 family) could be associated with temperature dependant heterosis for growth.

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Feldman, Moshe, Eitan Millet, Calvin O. Qualset e Patrick E. McGuire. Mapping and Tagging by DNA Markers of Wild Emmer Alleles that Improve Quantitative Traits in Common Wheat. United States Department of Agriculture, febbraio 2001. http://dx.doi.org/10.32747/2001.7573081.bard.

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The general goal was to identify, map, and tag, with DNA markers, segments of chromosomes of a wild species (wild emmer wheat, the progenitor of cultivated wheat) determining the number, chromosomal locations, interactions, and effects of genes that control quantitative traits when transferred to a cultivated plant (bread wheat). Slight modifications were introduced and not all objectives could be completed within the human and financial resources available, as noted with the specific objectives listed below: 1. To identify the genetic contribution of each of the available wild emmer chromosome-arm substitution lines (CASLs) in the bread wheat cultivar Bethlehem for quantitative traits, including grain yield and its components and grain protein concentration and yield, and the effect of major loci affecting the quality of end-use products. [The quality of end-use products was not analyzed.] 2. To determine the extent and nature of genetic interactions (epistatic effects) between and within homoeologous groups 1 and 7 for the chromosome arms carrying "wild" and "cultivated" alleles as expressed in grain and protein yields and other quantitative traits. [Two experiments were successful, grain protein concentration could not be measured; data are partially analyzed.] 3. To derive recombinant substitution lines (RSLs) for the chromosome arms of homoeologous groups 1 and 7 that were found previously to promote grain and protein yields of cultivated wheat. [The selection of groups 1 and 7 tons based on grain yield in pot experiments. After project began, it was decided also to derive RSLs for the available arms of homoeologous group 4 (4AS and 4BL), based on the apparent importance of chromosome group 4, based on early field trials of the CASLs.] 4. To characterize the RSLs for quantitative traits as in objective 1 and map and tag chromosome segments producing significant effects (quantitative trait loci, QTLs by RFLP markers. [Producing a large population of RSLs for each chromosome arm and mapping them proved more difficult than anticipated, low numbers of RSLs were obtained for two of the chromosome arms.] 5. To construct recombination genetic maps of chromosomes of homoeologous groups 1 and 7 and to compare them to existing maps of wheat and other cereals [Genetic maps are not complete for homoeologous groups 4 and 7.] The rationale for this project is that wild species have characteristics that would be valuable if transferred to a crop plant. We demonstrated the sequence of chromosome manipulations and genetic tests needed to confirm this potential value and enhance transfer. This research has shown that a wild tetraploid species harbors genetic variability for quantitative traits that is interactive and not simply additive when introduced into a common genetic background. Chromosomal segments from several chromosome arms improve yield and protein in wheat but their effect is presumably enhanced when combination of genes from several segments are integrated into a single genotype in order to achieve the benefits of genes from the wild species. The interaction between these genes and those in the recipient species must be accounted for. The results of this study provide a scientific basis for some of the disappointing results that have historically obtained when using wild species as donors for crop improvement and provide a strategy for further successes.

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Bonfil, David J., Daniel S. Long e Yafit Cohen. Remote Sensing of Crop Physiological Parameters for Improved Nitrogen Management in Semi-Arid Wheat Production Systems. United States Department of Agriculture, gennaio 2008. http://dx.doi.org/10.32747/2008.7696531.bard.

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To reduce financial risk and N losses to the environment, fertilization methods are needed that improve NUE and increase the quality of wheat. In the literature, ample attention is given to grid-based and zone-based soil testing to determine the soil N available early in the growing season. Plus, information is available on in-season N topdressing applications as a means of improving GPC. However, the vast majority of research has focused on wheat that is grown under N limiting conditions in sub-humid regions and irrigated fields. Less attention has been given to wheat in dryland that is water limited. The objectives of this study were to: (1) determine accuracy in determining GPC of HRSW in Israel and SWWW in Oregon using on-combine optical sensors under field conditions; (2) develop a quantitative relationship between image spectral reflectance and effective crop physiological parameters; (3) develop an operational precision N management procedure that combines variable-rate N recommendations at planting as derived from maps of grain yield, GPC, and test weight; and at mid-season as derived from quantitative relationships, remote sensing, and the DSS; and (4) address the economic and technology-transfer aspects of producers’ needs. Results from the research suggest that optical sensing and the DSS can be used for estimating the N status of dryland wheat and deciding whether additional N is needed to improve GPC. Significant findings include: 1. In-line NIR reflectance spectroscopy can be used to rapidly and accurately (SEP <5.0 mg g⁻¹) measure GPC of a grain stream conveyed by an auger. 2. On-combine NIR spectroscopy can be used to accurately estimate (R² < 0.88) grain test weight across fields. 3. Precision N management based on N removal increases GPC, grain yield, and profitability in rainfed wheat. 4. Hyperspectral SI and partial least squares (PLS) models have excellent potential for estimation of biomass, and water and N contents of wheat. 5. A novel heading index can be used to monitor spike emergence of wheat with classification accuracy between 53 and 83%. 6. Index MCARI/MTVI2 promises to improve remote sensing of wheat N status where water- not soil N fertility, is the main driver of plant growth. Important features include: (a) computable from commercial aerospace imagery that include the red edge waveband, (b) sensitive to Chl and resistant to variation in crop biomass, and (c) accommodates variation in soil reflectance. Findings #1 and #2 above enable growers to further implement an efficient, low cost PNM approach using commercially available on-combine optical sensors. Finding #3 suggests that profit opportunities may exist from PNM based on information from on-combine sensing and aerospace remote sensing. Finding #4, with its emphasis on data retrieval and accuracy, enhances the potential usefulness of a DSS as a tool for field crop management. Finding #5 enables land managers to use a DSS to ascertain at mid-season whether a wheat crop should be harvested for grain or forage. Finding #6a expands potential commercial opportunities of MS imagery and thus has special importance to a majority of aerospace imaging firms specializing in the acquisition and utilization of these data. Finding #6b on index MCARI/MVTI2 has great potential to expand use of ground-based sensing and in-season N management to millions of hectares of land in semiarid environments where water- not N, is the main determinant of grain yield. Finding #6c demonstrates that MCARI/MTVI2 may alleviate the requirement of multiple N-rich reference strips to account for soil differences within farm fields. This simplicity will be less demanding of grower resources, promising substantially greater acceptance of sensing technologies for in-season N management.

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Pullammanappallil, Pratap, Haim Kalman e Jennifer Curtis. Investigation of particulate flow behavior in a continuous, high solids, leach-bed biogasification system. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600038.bard.

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Recent concerns regarding global warming and energy security have accelerated research and developmental efforts to produce biofuels from agricultural and forestry residues, and energy crops. Anaerobic digestion is a promising process for producing biogas-biofuel from biomass feedstocks. However, there is a need for new reactor designs and operating considerations to process fibrous biomass feedstocks. In this research project, the multiphase flow behavior of biomass particles was investigated. The objective was accomplished through both simulation and experimentation. The simulations included both particle-level and bulk flow simulations. Successful computational fluid dynamics (CFD) simulation of multiphase flow in the digester is dependent on the accuracy of constitutive models which describe (1) the particle phase stress due to particle interactions, (2) the particle phase dissipation due to inelastic interactions between particles and (3) the drag force between the fibres and the digester fluid. Discrete Element Method (DEM) simulations of Homogeneous Cooling Systems (HCS) were used to develop a particle phase dissipation rate model for non-spherical particle systems that was incorporated in a two-fluid CFDmultiphase flow model framework. Two types of frictionless, elongated particle models were compared in the HCS simulations: glued-sphere and true cylinder. A new model for drag for elongated fibres was developed which depends on Reynolds number, solids fraction, and fibre aspect ratio. Schulze shear test results could be used to calibrate particle-particle friction for DEM simulations. Several experimental measurements were taken for biomass particles like olive pulp, orange peels, wheat straw, semolina, and wheat grains. Using a compression tester, the breakage force, breakage energy, yield force, elastic stiffness and Young’s modulus were measured. Measurements were made in a shear tester to determine unconfined yield stress, major principal stress, effective angle of internal friction and internal friction angle. A liquid fludized bed system was used to determine critical velocity of fluidization for these materials. Transport measurements for pneumatic conveying were also assessed. Anaerobic digestion experiments were conducted using orange peel waste, olive pulp and wheat straw. Orange peel waste and olive pulp could be anaerobically digested to produce high methane yields. Wheat straw was not digestible. In a packed bed reactor, anaerobic digestion was not initiated above bulk densities of 100 kg/m³ for peel waste and 75 kg/m³ for olive pulp. Interestingly, after the digestion has been initiated and balanced methanogenesis established, the decomposing biomass could be packed to higher densities and successfully digested. These observations provided useful insights for high throughput reactor designs. Another outcome from this project was the development of low cost devices to measure methane content of biogas for off-line (US$37), field (US$50), and online (US$107) applications.

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Ang, Andrew, Monika Piazzesi e Min Wei. What Does the Yield Curve Tell us about GDP Growth? Cambridge, MA: National Bureau of Economic Research, agosto 2004. http://dx.doi.org/10.3386/w10672.

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Litaor, Iggy, James Ippolito, Iris Zohar e Michael Massey. Phosphorus capture recycling and utilization for sustainable agriculture using Al/organic composite water treatment residuals. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600037.bard.

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Objectives: 1) develop a thorough understanding of the sorption mechanisms of Pi and Po onto the Al/O- WTR; 2) determine the breakthrough range of the composite Al/O-WTR during P capturing from agro- wastewaters; and 3) critically evaluate the performance of the composite Al/O-WTR as a fertilizer using selected plants grown in lysimeters and test-field studies. Instead of lysimeters we used pots (Israel) and one- liter cone-tainers (USA). We conducted one field study but in spite of major pretreatments the soils still exhibited high enough P from previous experiments so no differences between control and P additions were noticeable. Due to time constrains the field study was discontinued. Background: Phosphorous, a non-renewable resource, has been applied extensively in fields to increase crop yield, yet consequently has increased the potential of waterway eutrophication. Our proposal impetus is the need to develop an innovative method of P capturing, recycling and reuse that will sustain agricultural productivity while concurrently reducing the level of P discharge from and to agricultural settings. Major Conclusions & Achievements: An innovative approach was developed for P removal from soil leachate, dairy wastewater (Israel), and swine effluents (USA) using Al-based water treatment residuals (Al- WTR) to create an organic-Al-WTR composite (Al/O-WTR), potentially capable of serving as a P fertilizer source. The Al-WTR removed 95% inorganic-P, 80% to 99.9% organic P, and over 60% dissolved organic carbon from the agro-industrial waste streams. Organic C accumulation on particles surfaces possibly enhanced weak P bonding and facilitated P desorption. Analysis by scanning electron microscope (SEM- EDS), indicated that P was sparsely sorbed on both calcic and Al (hydr)oxide surfaces. Sorption of P onto WW-Al/O-WTR was reversible due to weak Ca-P and Al-P bonds induced by the slight alkaline nature and in the presence of organic moieties. Synchrotron-based microfocused X-ray fluorescence (micro-XRF) spectrometry, bulk P K-edge X-ray absorption near edge structure spectroscopy (XANES), and P K-edge micro-XANES spectroscopy indicated that adsorption was the primary P retention mechanism in the Al- WTR materials. However, distinct apatite- or octocalciumphosphatelike P grains were also observed. Synchrotron micro-XRF mapping further suggested that exposure of the aggregate exteriors to wastewater caused P to diffuse into the porous Al-WTR aggregates. Organic P species were not explicitly identified via P K-edge XANES despite high organic matter content, suggesting that organic P may have been predominantly associated with mineral surfaces. In screen houses experiments (Israel) we showed that the highest additions of Al/O-WTR (5 and 7 g kg⁻¹) produced the highest lettuce (Lactuca sativa L. var. longifolial) yield. Lettuce yield and P concentration were similar across treatments, indicating that Al/O- WTR can provide sufficient P to perform similarly to common fertilizers. A greenhouse study (USA) was utilized to compare increasing rates of swine wastewater derived Al/O-WTR and inorganic P fertilizer (both applied at 33.6, 67.3, and 134.5 kg P₂O₅ ha⁻¹) to supply plant-available P to spring wheat (TriticumaestivumL.) in either sandy loam or sandy clay loam soil. Spring wheat straw and grain P uptake were comparable across all treatments in the sandy loam, while Al/O-WTR application to the sandy clay loam reduced straw and grain P uptake. The Al/O-WTR did not affect soil organic P concentrations, but did increase phosphatase activity in both soils; this suggests that Al/O-WTR application stimulated microorganisms and enhance the extent to which microbial communities can mineralize Al/O-WTR-bound organic P. Implications: Overall, results suggest that creating a new P fertilizer from Al-WTR and agro-industrial waste sources may be a feasible alternative to mining inorganic P fertilizer sources, while protecting the environment from unnecessary waste disposal.

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Jander, Georg, e Daniel Chamovitz. Investigation of growth regulation by maize benzoxazinoid breakdown products. United States Department of Agriculture, gennaio 2015. http://dx.doi.org/10.32747/2015.7600031.bard.

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Introduction Previous research had suggested that benzoxazinoids, a class of defensive metabolites found in maize, wheat, rye, and wild barley, are not only direct insect deterrents, but also influence other areas of plant metabolism. In particular, the benzoxazinoid 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxa- zin-3(4H)- one (DIMBOA) was implicated in: (i) altering plant growth by interfering with auxin signaling, and (ii) leading to the induction of gene expression changes and secondary plant defense responses. The overall goal of this proposal was to identify mechanisms by which benzoxazinoids influence other aspects of plant growth and defense. Specifically, the following hypotheses were proposed to be tested as part of an approved BARD proposal: Benzoxazinoid breakdown products directly interfere with auxin perception Global changes in maize and barley gene expression are induced by benzoxazinoid activation. There is natural variation in the maize photomorphogenic response to benzoxazinoids. Although the initial proposal included experiments with both maize and barley, there were some technical difficulties with the proposed transgenic barley experiments and most of the experimental results were generated with maize. Summary of major findings Previous research by other labs, involving both maize and other plant species, had suggested that DIMBOA alters plant growth by interfering with auxin signaling. However, experiments conducted in both the Chamovitz and the Jander labs using Arabidopsis and maize, respectively, were unable to confirm previously published reports of exogenously added DIMBOA effects on auxin signaling. Nevertheless, analysis of bx1 and bx2 maize mutant lines, which have almost no detectable benzoxazinoids, showed altered responses to blue light signaling. Transcriptomic analysis of maize mutant lines, variation in inbred lines, and responses to exogenously added DIMBOA showed alteration in the transcription of a blue light receptor, which is required for plant growth responses. This finding provides a novel mechanistic explanation of the trade-off between growth and defense that is often observed in plants. Experiments by the Jander lab and others had demonstrated that DIMBOA not only has direct toxicity against insect pests and microbial pathogens, but also induces the formation of callose in both maize and wheat. In the current project, non-targeted metabolomic assays of wildtype maize and mutants with defects in benzoxazinoid biosynthesis were used to identify unrelated metabolites that are regulated in a benzoxazinoid-dependent manner. Further investigation identified a subset of these DIMBOA-responsive compounds as catechol, as well as its glycosylated and acetylated derivatives. Analysis of co-expression data identified indole-3-glycerol phosphate synthase (IGPS) as a possible regulator of benzoxazinoid biosynthesis in maize. In the current project, enzymatic activity of three predicted maize IGPS genes was confirmed by heterologous expression. Transposon knockout mutations confirmed the function of the maize genes in benzoxazinoid biosynthesis. Sub-cellular localization studies showed that the three maize IGPS proteins are co-localized in the plastids, together with BX1 and BX2, two previously known enzymes of the benzoxazinoid biosynthesis pathway. Implications Benzoxazinoids are among the most abundant and effective defensive metabolites in maize, wheat, and rye. Although there is considerable with-in species variation in benzoxazinoid content, very little is known about the regulation of this variation and the specific effects on plant growth and defense. The results of this research provide further insight into the complex functions of maize benzoxazinoids, which are not only toxic to pests and pathogens, but also regulate plant growth and other defense responses. Knowledge gained through the current project will make it possible to engineer benzoxazinoid biosynthesis in a more targeted manner to produce pest-tolerant crops without negative effects on growth and yield.

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Zhang, Chunxi, Fangfang Xie, Runchang Li, Ningxin Cui e Jiayuan Sun. Robotic-assisted bronchoscopy for the diagnosis of peripheral pulmonary lesions: A systematic review and meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, settembre 2022. http://dx.doi.org/10.37766/inplasy2022.9.0115.

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Abstract (sommario):

Review question / Objective: What is the overall diagnostic yield and complication rate of robotic-assisted bronchoscopy for peripheral pulmonary lesions? Condition being studied: Many of peripheral pulmonary lesions (PPLs) may represent early-stage lung cancer. Lung cancer is the leading cause of cancer mortality globally. Early diagnosis and treatment of lung cancer are crucial for a better prognosis. With the widespread use of low-dose computed tomography (LDCT), the detection rate of PPLs is increasing. As a result, the number of PPLs requiring biopsy is progressively increasing. Transbronchial lung biopsy (TBLB) and transthoracic needle aspiration (TTNA) are the main modalities of non-surgical biopsy for PPLs. TTNA has a diagnostic yield of 90%, however, it also has a pneumothorax rate of 25%. Since TBLB avoids destroying the structure of normal pleura and lung tissue, the incidence of complications is lower. Unfortunately, traditional flexible bronchoscopy has a modest sensitivity of 34% and 63% for lesions 2 cm, respectively. The advent of guided bronchoscopy has increased the diagnostic yield to 70%. However, there is still a gap in diagnostic yield compared with TTNA. The advent of robotic-assisted bronchoscopy (RAB) is expected to further improve the diagnostic yield of TBLB for PPLs. However, the diagnostic performance of RAB for PPLs has not reached a consensus.

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