The trends to improve representativeness of the assessments in the State Variety testing, productivity, ecological plasticity and homeostatic character of pea varieties

The trends to improve representativeness of the assessments in the State Variety testing, productivity, ecological plasticity and homeostatic character of pea varieties The purpose of the study is a comprehensive assessment of pea varieties on yield and adaptability parameters in the conditions of the forest-steppe zone of the Northern Trans-Urals. The object of the study is eight pea varieties of a leafless non-shattering morphotype (af, def), including seven morphotypes approved for use, which were tested in 2014-2016 at three different plots in the Tyumen region, located in the northern forest-steppe region. The variability of productivity and realization of its potential were determined by the technologies of B.A. Dospekhov and E.D. Nettevich, and the indexes of environment and ecological plasticity of the varieties by the methodologies of S.A. Eberhart and W.A. Russell. Stress resistance of the varieties was assessed by the quotations of A.A. Rossielle, J.Hemblin with A.A. Goncharenko comments, and their homeostatic character by the methodology of V.V. Khangildin. Genotypic effect of the varieties was evaluated by the recommendations on ecological variety testing of grain crops. The variety ‘Yamal’ (2.43 t/ha) showed the largest average productivity in nine different weather conditions (3 yearsX3GSU), the variety ‘Batrak’ (2.15 t/ha) showed the smallest results. The varieties ‘Omsky 9’ (53.9%) and ‘Salamanka’ (51.6%) produced its largest value on average in 2014-2016. The studied varieties were characterized with a significant changeability of productivity and low stress resistance. The varieties ‘Omsky 9’ and ‘Salamanka’ were characterized with the smallest changeability of productivity and the largest stress resistance. The varieties ‘Omsky 9’ (bi = 1,86), ‘Kumir’ (bi = 1,60) and ‘Agrointel’ (bi = 1,14) belong to the intensive varieties with the largest response to weather change. The rest of the varieties are characterized as plastic: their productivity variability correspond to variability of growing conditions. The varieties possess a low homeostatic character. The varieties ‘Omsky 9’ (Hom=2.39) and ‘Salamanka’ (Hom=1.49) possess the best homeostatic character. The varieties ‘Yamal’ ((Ei..=0.09) and ‘Salamanka’ (Ei..=0.08) showed the largest value of genotypic effect. The variety ‘Salamanka’ is considered the best variety for the north forest-steppe part of the Tyumen region due to the complex assessment of productivity and parameters of adaptability.