Reaction of sunflower varieties and hybrids to weather conditions and their adaptability parameters

Abstract

In regions with contrasting weather conditions, which include the Saratov region, it is necessary to conduct selection and evaluate breeding material not only in terms of productivity, but also in terms of adaptability to abiotic environmental factors. The experimental part was carried out on the experimental field of the Federal Agricultural Research Center for South-East Region in 2015–2021. There were 10 genotypes in the study, which were evaluated by the ability to form the highest productivity in different years in terms of moisture and heat supply. The HTC in the years of research was as follows: 2015 - 0.61, 2016 - 0.47, 2017 - 0.95, 2018 - 0.52, 2019 - 0.6, 2020 - 0.83, 2021 - 0.58. The coefficient of variation, stress resistance and genetic flexibility, the drought resistance index, and the coefficient of responsiveness to favorable growing conditions were indicators of adaptability. According to long-term data, the average yield of oilseeds of the studied varieties and hybrids varied from 1.98 to 2.54 t/ha. In some years, the yield of varieties Saratovskiy 20, Stepnoy 81, Stepnoy 82, Lyubimchik and hybrid YuVS 7 exceeded 3.0 t/ha. In 9 out of 10 varieties and hybrids, a high variability of the trait is noted (V = 21.7-33.1%). The average yield variability was found in the UVS 3 hybrid (V = 19.1%). Varieties Stepnoy 81, Lyubimchik are characterized by high genetic flexibility ((Ymin + Ymax)/2 = 2.50 and 2.75, respectively) and responsiveness to favorable environmental conditions (Kp = 2.52 and 2.23, respectively). The hybrid YuVS 3 is characterized by high stress resistance (Ymin + Ymax = -1.15) and drought resistance (DSI = 0.92). High genetic flexibility ((Ymin + Ymax)/2 = 2.45) and drought resistance (DSI = 0.98) had  SVS 7. It is advisable to include varieties and hybrids with high adaptive properties in the further breeding process as initial material.