Abstract
The research was carried out in order to increase the productivity of oilseed flax and spring rape in Northern Kazakhstan. Experimental studies were conducted from 2012 to 2014 in Kostanay research Institute of agriculture (Republic of Kazakhstan). The experiment studied the sowing of flax and spring rape – 2nd decade of May; 3rd decade of May; 1st decade of June and the seeding rate for flax is 6.5; 7.0 and 7.5 million viable seeds/ha for spring rape – 2, 0; 2.5 and 3.0 million viable seeds/ha. During the years of research, the best coefficient of water consumption of the studied crops showed the second sowing period the third decade of May. According to the seeding standards, the formation of an optimal stem density increased the efficiency of moisture use. It was noted that moisture was most rationally consumed when sowing oilseed flax with a norm of 7.0 million sunflower seeds/ha (16.5-17.7 mm/c), spring rapeseed with a seeding rate of 2.5 million sunflower seeds/ha (9.9-11.2 mm/c). Oilseed flax sowing in the 3rd decade of May with a seeding rate of 7.0 million seeds/ha allowed to obtain the highest indicators of plant productivity in the experiments: yield is 13.1 c/ha, oil yield is 5.4 c/ha. In spring rape, the optimal sowing period was also the third decade of May; according to the seeding rate, the variant of 2.5 million suns excelled. seeds/ha sown in a given period: yield is 22.9 c/ha, oil collection is from 1 ha 9.4 c.