ECOLOGICAL PLASTICITY AND STABILITY OF WINTER WHEAT VARIETIES IN THE CONDITIONS OF SOUTHERN UKRAINE.

The aim of the research was to study the ecological plasticity and stability of winter wheat varieties under the arid conditions of the southern steppe of Ukraine. The research was conducted during 2015/16‒2019/20 at the Institute of Irrigated Agriculture, NAAS, and the Askanian State Agricultural Research Station, Kherson region, Ukraine. The material for the research was 10 varieties of winter wheat which were sown under conditions of optimal (irrigation) and stress (without irrigation) moistening. The response of winter wheat cultivars to growing conditions was analyzed using regression coefficient, homeostatic parameters, general adaptability, variance of specific adaptability, selection value of genotype and others. The minimum yield of varieties varied from 2.02 t ha^-1 to 3.72 t ha^-1 and the maximum - from 8.10 to 9.81 t ha^-1. The obtained results are a contribution to the study of both theoretical and practical aspects of wheat drought resistance and can be used as elements of selection programs. [ABSTRACT FROM AUTHOR]