ASSESSMENT OF ECOLOGICAL PLASTICITY AND STABILITY OF SPRING BARLEY

Spring barley breeding in the Rostov region is aimed at developing early maturing, drought-resistant, high-yielding varieties with good technological qualities of grain. Productivity is mainly affected by the economic and biological parameters of the variety and the environmental conditions in the growing area. The purpose of the research is to conduct a comparative assessment of spring barley varieties by indicative parameters of ecological plasticity and yield stability to changes in environmental conditions. In 2018-2020, for a targeted study of this impact, trials with 18 spring barley varieties of Russian and foreign breeding to estimate their ecological adaptability and stability were carried out. Square of the plot – 10 m2; experiment was replicated thrice. Soil – chernozem ordinary with humus content in the arable layer at the level of 3.0–3.5%, pH = 7.0–7.1. Phosphorus content – 15–20 mg/kg of soil, exchangeable potassium – 300–500 mg/kg. The estimation of the effect on the ecological plasticity and stability of varieties was carried out according to the method of S.A. Eberhart, W.A. Rassel edited by V.A. Zykin (2005). Indicators of homeostaticity and breeding value were calculated according to the V.V. Khangildin and N.A. Litvinenko method (1981). Over the years of research, the productivity formation was mainly influenced by the factors ‘variety’ (66.1%) and ‘year’ (31.7%). The environmental conditions index showed that more favorable growing conditions were in 2020 (Ij = +0.23); in 2018, on the contrary, they were relatively unfavorable (Ij = –0.19). As a result of the three-year analysis, the highest productivity was identified in the varieties ‘Format’ (4,9 t/ha), ‘Fedos’ (4,8 t/ha) and ‘Gris’ (4,8 t/ha). In general, according to the complex of adaptivity parameters, ‘Format’ variety was distinguished. It has high indicators of breeding value (Sc = 4.6), stress resistance (Ymin-Ymax = –0.3), high stable productivity, as well as a high homeostatic index (Hom = 531) and a low coefficient of variation (V = 3.1%).