This work deal with formation of winter wheat yield. Winter wheat was grown after three different previous crops: trifolium, potatoes, PCC. The experiment was aimed on creating yield components: numer of plants per square meter, numer of grains per spike, the weight of one thousand grains. There were performed measurements dutiny the vegetation and there was calculated theoretic and real yield.

The complex interaction of genetics, environment and management in determination of crop yields can interfere with selection progress in breeding programs. Specifically, the impact on selection for nitrogen use efficiency (NUE) in wheat (Triticum aestivum L.) under changing climatic conditions can be confounded by these interactions. Temperature increases for the southeastern United States are projected to range from 1-3°C by 2050 with nighttime temperatures increasing more rapidly than day temperatures. High temperatures are known to affect crop development and breeding for tolerance to heat stress is difficult to achieve in field environments. We utilized a multi-environment trial to assess variation in traits associated with NUE based on interactions of genotype x environment x management (G×E×M). All genotypes in the study responded favorably to lower than recommended nitrogen rates. Incremental application of N rates increased yield and post-anthesis N uptake significantly. Additionally, two multi-year studies investigating the effects of heat stress on soft red winter wheat varieties were conducted during the 2015-2016 growing seasons at the University of Kentucky Spindletop Research Farm in Lexington, KY. Thirty-six to 40 genotypes were chosen based on the combination of traits for vernalization and photoperiod sensitivity determined using marker analysis. Warmed environments were created through active and passive warming. Heading date, averaged across genotypes, shifted 1-5 days earlier in the actively warmed environment compared to the ambient environment across both years (p ≤0.05). Grain yield, averaged across genotypes, was significantly reduced in the actively warmed environment by 211.41 kg ha-1 (p ≤0.05) or 4.84%; however yield response to environment varied among genotypes with several genotypes displaying an increased yield in the warmed environment. Night temperature increases ranged from 0.27-0.75 °C above ambient temperature in the passively warmed environment. Grain yield, averaged across genotypes, was significantly reduced in the passively warmed environment by 224.29 kg ha-1 (p ≤0.05) or 6.44%; however, yield response to environment varied among genotypes with several genotypes displaying an increased yield in the warmed environment. Yield reductions are attributed to nitrogen utilization being reduced by 9.4% (p ≤0.001) under increased night temperatures.

In this diploma thesis the influence of the nitrogen fertilization and drought on the change in the content of gliadin protein fractions in two genotypes of winter wheat Avenue and Tobac was studied. These two genotypes differ in vegetation time length. Half of the plants were fertilized using nitrogen fertilizer at 200 kg N/ha. One third of the plants were cultured under the conditions of early drought (in bloom season), other one third was grown under the conditions of of late drought (grain filling season), and last third was grown under the conditions of natural irrigation. Individual gliadin fractions were separated by using A-PAGE method and their content quantified by computer densitometry. Our results have shown increase in gliadin fractions content after nitrogen fertilization. Early drought itself caused significant increase in the levels of -gliadin fractions in Tobac genotype. Early and late drought in combination with nitrogen fertilization increased levels of gliadin fractions in Tobac genotype. Early drought in combination with nitrogen fertilization had no effect on Avenue genotype, except of -gliadin fractions which decreased significantly. Late drought in combination with nitrogen fertilization caused significant increase in gliadin content in Avenue genotype. The highest increase in gliadin content was observed in fraction -5 of the Tobac variety during interaction nitrogen fertilization with late drought.

This diploma thesis deals with an influence of elevated concentration of carbon dioxide (700 mol·mol-1) on the protein content of gliadin fraction in winter wheat (Triticum aestivum) early var. Avenue and late var. Tobac. To separate gliadin, the A-PAGE method was used, proteins were quantified by computer densitometry. Signitificant influence of genotype on the gliadin fraction of the gluten proteins was found. Due to the increased concentration of CO2, the content of the gliadin fraction of the Avenue variety was reduced, while the content of the gliadin fraction of the Tobac variety increased. Effect of elevated CO2 concentration was at var. Avenue showed a significant difference in total content of gliadin fraction and fraction 1,2-gliadins. A significant difference was found in the var. Tobac only in the fraction 1,2-gliadin.

Dough strengtheners are the most common and largest group of chemicals used in bread formulations. This study evaluated the capability of hard red spring (HRS) wheat flour to replace commercial dough strengtheners in bread production. Doughs were prepared by blending different percentages (10%, 20%, 30% and 40%) of four different HRS wheat flours with hard red winter (HRW) wheat flour. In addition, doughs were prepared by adding ten commercially available additives with HRW wheat flour to compare the dough strengthening ability of HRS wheat flour. All the HRS wheat flour blends had significantly (p<0.05) strong dough rheological characteristics than most of the additives. The 40% blends of HRS wheat cultivar Glenn and Linkert had better bread making quality than other blends and all the additives. The SE-HPLC unextractable protein fractions of these two cultivars also showed a better correlation with bread making properties than all the additives.

This study compared the effects of nitrogen sources on the available inorganic soil nitrogen, nitrogen movement, nitrogen losses, and wheat yields when nitrogen fertilizers were applied to soil planted to dryland winter wheat at the Blue Creek Experimental Station in northern Utah. In the fall 1973 soil samplings, the fertilizers producing the largest mineral nitrogen contents in the 0-30 cm soil depths were ammonium nitrate >ammonium sulfate > S-coated urea, when they were broadcast at the practical rate of 56 kg N/ha. There was no increase in the mineral nitrogen at the dee per depths in the fall or at any depth in the following spring. Statistically, the three nitrogen sources did not increase grain yield significantly but did increase grain protein content and nitrogen content in grain. Ammonium nitrate and potassium bromide at the rates of 400 kg N and 200 kg Br/ha were broadcast to soil planted to winter wheat in October 1974. Nitrate-nitrogen and bromide distribution patterns in the soil profile looked alike in May 1975. These showed that their movements were similar. Considerable nitrate-nitrogen (35 percent of the added nitrogen) had moved down below the 120 cm depth. The highest nitrate-nitrogen concentrations were found at the 45 to 90 cm depth. There seems to be evidence that nitrate-nitrogen and bromide had moved deeper than the 150 cm depth. Ammonia-nitrogen losses from nitrogen fertilized soils were conducted in the laboratory. Ammonium sulfate, ammonium nitrate, or urea applied to the soil surface lost ammonia-nitrogen differently. From noncolcoreous soil, the ammonia-nitrogen loss was greatest from urea. From calcareous soil or soils receiving carbonates or high soil pH by the addition of sodium hydroxide solution, the greatest losses were from ammonium sulfate. High losses were favored by high temperatures and longer periods of moist soil. The total amounts of water lost from the soil was not closely related to the total ammonia-nitrogen loss during two weeks. No loss of ammonia-nitrogen occurred when nitrogen fertilizers were applied at a 2.5 em depth or deeper. The ammonia-nitrogen losses were also greatly reduced when nitrogen fertilizers applied to the soil surface was followed by irrigation or heavy rainfall. In the field, the higher temperatures increased the ammonia-nitrogen losses from ammonium sulfate, ammonium nitrate, and urea when applied to both a noncalcareous and a calcareous soil. However, the loss from calcareous soil was reduced by irrigation following fertilizer application. No ammonia-nitrogen was observed when ammonium sulfate was applied to o 2.5 cm soil depth, despite of the high soil temperature during the day time in moist soil. Rapid drying of the moist soil surface quickly reduced the losses per day.

Winter wheat, with an annual average acreage of about 300,00o acres, forms an integral part of the farm economy of Utah. For many years intermountain agronomists and farmers alike have known dry-land wheat production to be limited by low summer rainfall. In the past 15 years, however, it has become apparent through intelligent research that in many cases lack of nitrogen has been the limiting factor. When this occurs, winter wheat production can be increased by correcting this nitrogen deficiency. It has also become apparent that a lack of nitrogen is responsible for much of the ppor quality wheat received by wheat processors form certain areas of the United States. To supple the neede nitrogen broth commercial fertilizers and green-manure crops have been used, but of particular importance at this time are commercial fertilizers. Unitl 1949 investigators of this problem used soil applications of either organic or inorganic nitrogen fertilizers in their studies. In that year Finney and Shellengerger (Kansas State College) began the first of their tests using "NuGreen" a synthetic urea fertilizer containing 44% nitrogen, as a foliage spray. Other experiemtns have shown that if large amounts of nitrogen fertilizer are added to dry farm wheat during a dry year, the yield may actually be reduced because the early vegetative growth is stimulated and the limited soil moisture is not able to bring about satisfactory maturity. It would seem that if nearly all of the nitrogen were withheld until the what was nearly mature, and then added as a spray, the danger of excessive early stimulation might be avoided while the protein content of the wheat might be increased. The results obtained by all of these tests were encouraging enough to warrant a study here in Utah of winter wheat fertilization involving the use of "NuGreen". It was proposed that the study be conducted on dry lands representative of intermountain conditions, and that it cover a two-year period. It was inteded that in the first year a preliminary of "feeler" test would be conducted to determine whether or not it was feasible to spray nitrogen on wheat. The intent was, that if favorable resutls were secured, this preliminary test would be followed in the second year by a more extensive study to obtian detailed information as to what effect urea spray might have on winter wheat. Objectives of these studies were: 1. To find the stage of maturity of the wheat plant at which urea spray would give the greatest protein increase. 2. To fidn the stage of matureity of the wheat plant at which urea spray would give the greatest yield increase. 3. To determine what amount of nitrogen, when supplied as urea, would tive the greatest stimulus to yield and protein, or both. 4. To compare the accepted practice of supplying nitrogen by soil application with the new method of adding it as a foliage spray.

No description available.

No description available.

No description available.