SEL’SKOKHOZYAISTVENNAYA BIOLOGIYA [AGRICULTURAL BIOLOGY], 2015, V. 50, ¹ 1, pp. 85-91 ISSN 2313-4836 (Online) Plant plasticity in response to environmental factors doi: 10.15389/agrobiology.2015.1.85rus doi: 10.15389/agrobiology.2015.1.85eng PRODUCTIVITY AND ECOLOGICAL PLASTICITY OF PLUM ( ) VARIETIES UNDER ENVIRONMENTAL INSTABILITY R.Sh. <...> Pobedy, Krasnodar, 350901 Russia, e-mail zaremuk_rimma@mail.ru A b s t r a c t In perennial crops, particularly in plum trees, a genotypic (varietal) ecological plasticity as the ability to respond to external changes and anthropogenic factors is little studied. <...> Plum tree is one of the most adaptive and wide spread fruit crop peculiar in its drought resistance, winter hardiness, high and sustainable fruit production. <...> However, plum varieties significantly differ in valuable traits and ecological plasticity. <...> Here we show the data on yield, fruit size and plasticity of differently originated plum varieties under conditions of four soil and climatic zones of Krasnodarskii krai. <...> The data were obtained by statistical processing results of varietal testing. <...> The main regional varieties Kabardinskaya rannyaya, Renklod Altana, Vengerka italianskaya, Anna Shpet, Vengerka azhanskaya and Tuley Gras were assessed. <...> The role of the genotype in adaptation to environment indicated by fruit size and yield as an integrated parameters of the response to adverse condition was studied. <...> In some varieties the yield varied from 18.0 до 50.0 centner per ha but did not exceed an average value for all varieties in each zone. <...> Higher average yield for all zones was observed in Stenley variety at 165-170 centner per ha, in Anna Shpet variety at 115-145 centner per ha, in Kabardinskaya rannyaya variety at 130.4-147.9 centner per ha, and it was a little bit lower in Renklod Altana and Tuley Gras while the lowest in Vengerka azhanskaya and Vengerka italianskaya varieties. <...> The yield was shown to be specific to genotype as a varietal biological peculiarity influencing the yield at 51.6 % rate, and also it depends on weather condition of the year with 28.7 % influence, and on their interaction at 17.2 % influence. <...> Definite effects were shown for additional factors such as scheme of planting, type of crown, mineral nutrition, protection measures against diseases and pests. <...> Fruit size was shown to be a varietal parameter <...>