XVI International Botanical Congess

Breeding of cultivars with high and stable yields is especially actual for Kazakhstan due to its contrast natural conditions. One of central ways in this direction in the current breeding programs is studying of Genotype - Environment Interactions, which sets the tasks of determination samples reaction rates to the environment changes. In this relation the reaction rates of 66 samples of spring barley collection by 7 quantitative indices have been studied by 2 methods. The use of statistical methods (regression, factorial) allowed to range barley samples in the two coordinates (productivity and adaptivity) and to receive the following scale of varieties ranks: productive and stable (4), middle productive and stable (7), low productive and stable (7), high productive an stable (16), middle productive and plastic (5), low productive and plastic (12). The application of cluster methods made possible to group cultivars with similar rate of reaction by total indices in accordance withy the breeding purpose.