HE PECULIARITY OF TRAIT FORMATION "THICKNESS OF THE SECOND INTERNODE STRAW" AND ITS SIGNIFICANCE IN THE SELECTION PROCESS TECHNOLOGY OF WINTER WHEAT
The purpose of the research. The article contains data on the peculiarities of the formation of a number of traits: 1) «thickness of the straw of the second internode» (TS-2M), mm; 2) «number of grains in the head» (KZ), pcs; 3) «weight of the grain of the head» (M<sub>1</sub>), g; 4) «weight of the grain head» (M<sub>3</sub>) g; in winter soft wheat (Triticum aestivum L.). The analysis of the experimental data shows the importance of using the trait «thickness of the straw of the second internode» (TS-2M) in the varieties and breeding lines of winter wheat on the productivity tests, especially in the early stages of breeding. The methodology. The research, including field, laboratory observations and experiments, were carried out at the experimental breeding site of the Poltava State Agrarian Academy, according to the methodological guidelines “Methods of field research”: Dospekhov B. A., 1985; and Eshchenko V. O. “Fundamentals of scientific research in agronomy”, 2005. The object of the research was investigation of varieties and breeding lines of soft winter wheat of various genetic and geographical origin using different sowing dates. Results. As a result of the conducted studies, it was found that with an increase of the thickness of the straw of the second internode in varieties and breeding lines of winter wheat, such traits like the weight of grains per head, the number of grains per head and the weight of the head with grain increases, which, in turn, it makes possible to conduct effective selections, which are an integral and main part of selection to increase the yield of winter wheat. Scientific novelty. Targeted breeding of winter wheat using the thickness of the straw of the second internode will increase the productivity of not only the wheat plant, but also the output of products per unit area.