ECOLOGICAL PLASTICITY PARAMETERS OF THE COMMON BEAN GRAIN TYPE IN THE CONDITIONS OF THE OREL REGION

The parameters of ecological plasticity and stability in terms of seed yield were studied in 12 varieties of common beans (Phaseolus vulgaris (L.) Savi.) of grain type of different breeding periods under the conditions of the Orel region. The seed yield of bean varieties depended on the conditions of the growing season. From the analysis of the environment index for each year of research, it follows that the growing conditions of 2012, 2013 and 2019 were not favorable for the crop, the environment index (Ii) took a negative value. Favorable weather and climate conditions have developed in 2020, Ii= 0,30. The maximum increase in seed yield in the studied varieties was observed in 2020. The largest seed yield in 2020 was obtained from varieties: Strela - 3.70 t/ha, 1.15 t/ha more than the minimum seed yield obtained in 2019; and Marquise in 2020, the yield was 3.25 t/ha, 0.85 t/ha more than the minimum value for the years of research obtained in 2019 (varieties of the breeding 2016-2020). Also in 2020, a high yield was noted in the Kustovaya variety without fiber 85 - 3.00 t/ha, more by 1 t/ha than in 2013 (breeding 1940-1950), and for the Gornal variety - maximum yield over the years of the study - 3.05 t/ha (breeding 1980-2000). According to the results of the analysis of the regression coefficients of varieties (bi), it was found that the varieties Strela and Markiza (bi = 1.76 and bi = 1.53, respectively) belong to varieties of intensive type; varieties: Saksa without fiber 615 variety - bi=0,24, Rubin bi= 0,25, Shokoladnitsa bi=0,05, Nerussa, bi=0.15 had a reaction close to neutral to changing growing conditions (extensive varieties). The values of the coefficient of ecological stability σ2 d were established. Among the studied varieties of common bean, the maximum values of the coefficient σ2 d were observed in varieties Strela and Marquise: σ2 d = 0,068, σ2 d = 0,052, which indicates a lower, in comparison with others, environmental stability; the variety Shokoladnitsa has a high degree of ecological stability (σ2 d = 0,0001). As a result of the analysis of variance, it was revealed that the seed yield in the years of the study depended on the prevailing weather conditions by 29.8%; the influence of the genotype on the degree of manifestation of the trait was 23.8%. The interaction of factors genotype × environment influenced the yield by 4.8%. Thus, the analysis showed that the varieties Marquise and Strela, which have a high coefficient of ecological plasticity, characteristic of varieties of the intensive type, can be recommended as a source material for creating varieties with a high genotype responsiveness to favorable changes in growing conditions. Varieties Saksa without fiber 615, Rubin and Shokoladnitsa were characterized by low values of the coefficient of ecological plasticity bi < 0.30, varieties with a weak or neutral response to changes in growing conditions (extensive varieties), which allows us to recommend them as sources for creating varieties intended for cultivation in an environment less favorable for common beans.