Influence of sowing time on the yield of spring wheat in Northern Kazakhstan

The research was carried out in order to determine the most optimal terms of sowing spring wheat when cultivating on a stubble precursor conditions southern chernozems Kostanay region. «Omskaya 18» variety were studied: May 15 (control), 18, 22, 25, 27, 30 and June 05 fields 4-field grain-steam (steam – wheat) crop rotation.Soil cultivation technology- No-till.Records observations according standard generally accepted methodology. An agrochemical survey at experimental site showed that before sowing, soil supply with nitrate nitrogen characterized as low, mobile phosphorus average, exchange potassium very high. On for 2018-2020 years research, reserves productive moisture during good. It found low average 1.47t/ha, yield early date 15, 2020, primarily due lack precipitation high temperatures, which fell critical phase development crop, affecting grain filling. For period apparently increased. As matter fact results get up +0,43 t/ha per hectare from 25th may 1,90-1,99 tons average. revealed dates are reflected quality. So, an decreases full-scale weight, meanwhile 22th till 5th formed grains second class.