FEATURES OF THE CROP STRUCTURE AND ITS RELATION WITH PRODUCTIVITY IN BREEDING LINES OF SPRING BREAD WHEAT OF DIFFERENT MORPHOTYPES IN EAST KAZAKHSTAN IN 2020

In East Kazakhstan, due to climate change and the progress of agriculture, there is a need to create and introduce varieties of spring bread wheat of intensive type. For the first time in the research area, the authors began the creation, selection and comparative study of breeding culture lines differentiated by morphotypes: semi-dwarfs (plant height 66...80 cm), medium-sized (81...95) and tall (from 96 cm). In 2020, in the SN-2 nursery, these three groups of lines were studied by yield, its components (15 simple and 16 index ones) and by the nature of correlations between the signs of the crop structure and the productivity of the plot. The purpose was to determine the features of the crop structure and the correlations of its elements with the yield in each group, as well as a preliminary assessment of the morphotypes for compliance with the chosen strategy to intensification.
The analysis of the crop structure revealed that the characteristics associated with linear size and biomass increase from semi-dwarf to high lines; the number of sterile spikelets and indices (relative productivity and grain number), on the contrary, decrease; the mass of 1000 grains is approximately the same, and the group of medium-sized lines has an advantage in a number of parameters of individual productivity.
Correlation analysis showed that in semi-dwarfs, the yield was associated with the number of plants and the densification of the ear; weak correlations were noted with the height of the plant and the weight of 1000 grains. The prospects of this group in the research area are recognized as controversial, and the need for further study is suggested. The tall lines showed extensive patterns: the height of the plant was associated with the yield and weakly –biomass, the number of spikelets, overall vitality (a negative relationship with the filling index).