No abstract

Durum wheat is second in importance after soft wheat for many countries of the world, its area is about 10% of common wheat sowing, and world grain production reaches 15-20 million tons. Identification of the role of climatic predictors in the formation of spring durum wheat on Based on the construction of computer models using the methods of mathematical modeling, it is of particular importance for agriculture.Earlier studies to identify the relationship between indicators of grain quality of durum wheat and weather predictors allowed us to establish that the formation of indicators of grain quality occurs under different weather conditions.In the work on the basis of a large experimental material on the quality of grain of two varieties of spring durum wheat, agrometeorological data of the Orenburg Regional Center on Hydrometeorology and environmental monitoring for May-August 1967-2017. Multiple regression models of the influence of weather predictors on the main indicators of the quality of hard wheat grain were built. Based on the solution of the system of regression equations, an integral indicator of the quality of spring hard wheat grain was developed for conditions of a sharply continental climate.

The paper presents the study of daily course transpiration of the three upper leaves of cultivars of spring hard wheat of different origin, grown against the background of two methods of primary tillage in different conditions of the vegetation period according to weather factors. The studies were carried out according to the method of rapid weighing using the torsion scales VT-500 three times during the day (9:00, 12:00 and 15:00 hours) in the phases of stem elongation and wheat earing. The paper identifies cultivar specificity of the course of daytime transpiration, the influence of soil tillage methods on the amount of transpiration, as well as a significant dependence on weather factors over the years of study. The results can be used in practical breeding with the perspective assessment of varieties according to the transpiration activity of the leaves in the most important phases of the spring wheat growing season. In connection with changes in the climatic factor in the direction of increasing aridity, it is important to know the patterns of the response of the plant organism to the extreme conditions and the possibility of its use in breeding practice. The results obtained can substantiate the needs to use various methods of basic processing to reduce negative weather factors.