THE STUDY OF PRODUCTIVITY AND YIELD STRUCTURAL ELEMENTS OF WINTER BREAD WHEAT (T. aestivum L.) GENOTYPES UNDER RAINFED CONDITIONS.

The paper is dealing with the effects of the late drought stress on the productivity and yield components of 12 varieties and 7 lines of winter bread wheat, which differ in morphophysiological characteristics. It was found that drought stress created in the late period decreased productivity, number of spikes per sheaf, number of spikelets per spike, number and mass of grains per spike and mass of 1000 grains by 19.9%, 7.7%, 4.9%, 12.8%, 21,6%, and 10.01%, respectively. As can be seen, of the components directly affected by water stress, the productivity and grain mass per spike were the most depressed, while number of spikes per unit area and number of spikelets per spike was relatively stable. Under late drought stress, Gobustan and Gyrmyzy gul 1 varieties, 7thWON-SA No.465 and Ferrigineum 2/19 lines manifested the highest productivity (557, 515, 607, and 549 g/m², respectively). Under drought stress, the most depressed values for 1000-grain mass were found for the genotypes Tale 38, Gyrmyzy gul 1, 12thIWWYT No.8, and Ferrigineum 2/19, while the least depressed values were found for Sonmez 01, Gobustan, 4thFEFWSN No.50 and 7thWON-SA No.477. [ABSTRACT FROM AUTHOR]