Ecological plasticity of winter rapes as the basis of its cultivation efficiency in the zone of unstable moistening

As a result of ecological variety testing of promising winter rape varieties of All-Russian Research Institute of Oil Crops selection in the fields of the Armavir experimental station in 2016-2019, it was found that all the studied varieties had a sufficiently high plasticity and adaptation to difficult local climatic conditions. Wintering of winter rapeseed plants averaged 90-96%. The adaptability of varieties was particularly pronounced during the growing season of 2017-2018. Under the influence of adverse weather factors, including the spring-summer drought, the duration of almost all phases of vegetation of winter rapeseed was reduced by several days. And the height of the crop plants decreased on average by 9-44 cm compared with more moistened years of research. But, despite this, most of the studied varieties have lost no more than 35% of the yield, obtained in 2017 and 2019, the years favorable for vegetation. It was also found, that in all the years of observation, the Sarmat variety was the most stable and productive (2.92-4.23 t/ha) among the studied samples of winter rape. The Elvis variety had the highest oil content - 46.5-48.4%. But due to the high yield, the Sarmat consistently provided the highest oil harvest per hectare, that is 1.19-1.81 t/ha. Thus, as a result of the environmental assessment, it was revealed that Sarmat is one of the most promising varieties of winter rape selected by All-Russian Research Institute of Oil Crops for cultivation in the zone of unstable moistening. The relatively high level of profitability of its production (up to 75%) in the dry year of 2018, is a significant justification for the possibility of growing this variety in the zone of insufficient moistening.