DETERMINATION OF ECOLOGICAL STABILITY AND PLASTICITY OF PARENTAL COMPONENTS OF MAIZE HYBRIDS IN RELATION TO GRAIN YIELD

Abstract

Statement of the problem. Parental components are characterized by significantly lower viability, weakened growth, weaker root system, and as a result are more susceptible to adverse factors and have a lower yield level compared to F1 hybrids. This affects the volume of seeds obtained from parental components and F1 hybrids, the stability of their production and cost. In this regard, the study and evaluation of environmental plasticity and stability of parental components, their adaptation to real natural and climatic situations is an urgent issue of the modern process of corn seed production. The purpose of the study is to determine the ecological stability and plasticity of the parental components of maize hybrids in relation to grain yield under different weather conditions. Materials and methods of the study. The research was conducted at the Institute of Cereals of the National Academy of Agrarian Sciences of Ukraine during 2018‒2021. In the experiment, 15 parental components of corn hybrids were used. For calculations, the methodology developed by Eberhart S.A., Russel W.A., which is based on the calculation of two parameters: the linear regression coefficient bi (environmental plasticity) and the variance σd² (environmental stability). Results. The grain yield of the parental components of maize hybrids for four years was determined, the influence of environmental conditions on the yield was established, and the parental components were divided into groups according to their ecological plasticity and stability in relation to grain yield. Conclusions. The most valuable, high-intensity, parental components DK 315 SVZM, DK 633/325 MV, DK 315 M sterile and TT 005 were identified, which can be grown in different environmental conditions, but will provide maximum yield on a high agro background under favorable weather conditions; and less valuable DK 239 M and DK 2064 M, which are desirable to grow only on a high agro background under favorable climatic conditions, where they will give the maximum return; and semi-intensive DK 777 M, DK 777 ZMSV and DK 680 MVZS, which are better to use on an extensive background, where they will give the maximum return at a minimum cost.