Influence of the predecessor and the seeding rates on the rape productivity

The aim of the research is to identify the optimal seeding rate of varieties and hybrids of spring rape for seeds in the conditions of Northern Kazakhstan. The subject of the research is varieties and hybrids of spring rape. On the experimental fields of the Esil state grain-feed variety seed-trial ground, located in the Republic of Kazakhstan, North Kazakhstan region, the Esil district, the village of Yavlenka, in 2019-2020, a competitive test of spring rape was carried out, represented by 5 varieties: Geros, Maikudyk, Hunter, Makhaon and 3 hybrids: Caliber, Builder, GEN0009. The study of varieties and hybrids was carried out against the background of the predecessor - pure fallow, according to several seeding rates, namely 2.0, 2.5 and 3 million viable seeds. The main counts and observations were carried out according to the approved methodology of state variety testing. The studies carried out made it possible to establish that the seed productivity of rape plants is closely related to the meteorological conditions of the growing season and the studied variants of the experiment. Having studied the seeding rates, we came to the conclusion that the highest productivity is provided by rapeseed with a seeding rate of 2.0 million and 2.5 million viable seeds, and with an increase in the seeding rate, the yield decreases. Of the samples presented, over the years of testing, the variety Maikudyk and the hybrid Bilder distinguished themselves by a constant and full-fledged harvest for a number of selected characteristics.