Influence of the North Kazakhstan Plains Weather on the Productivity of the Spring Soft Wheat

Spring soft wheat is a primary agricultural crop of North Kazakhstan, the growing process of which is done in harsh weather conditions due to the fact, that early spring drought and the biggest rainfalls at the end of June and beginning of July, are normal in the region. Due to this fact, scientists and producers have mistakenly believed that in the Northern region, spring wheat should be sown later, adjusting the main phase of plant development “tillering – stem elongation” under the maximum summer rainfalls. The research aims to establish the dependence of spring wheat yield on the amount of spring-summer rainfall at different sowing periods. The following methods were used in the research: field method, methods of clustering, variation, correlation and dispersion analysis. Analysis of observations from 2012-2021 showed that years with an early-spring drought and mid-summer maximum rainfalls were less than one-third of ten and about 60% were years with no spring drought, although the maximum rainfall period was shifted to the June month. However, only one year (10%) was characterized by a severe spring drought and a shift of summer rainfalls to August. The highest yield (26.9 c/ha) of the studied wheat species was observed in years with an atmospheric precipitation shift at the beginning of the summer period and early sowing date. During years of early spring drought with the biggest rainfall in mid-summer, relatively high yields (20.5 cwt/ha) are observed in the later sowing dates. The practical value of the research is determined by the fact, that in Northern Kazakhstan the sowing dates of spring wheat are not closely tied to the calendar dates and depend significantly on the climatic conditions of the region and the weather conditions that prevailed in the spring and summer period of a specific year