Влияние засухи и высоких температур на урожайность и качество зерна фиолетовозерных линий яровой мягкой пшеницы

Abstract

This paper was aimed at the impact of drought and high temperatures on the main stages of plant development, yield, grain protein content (GPC) and its composition as well as content of phenolic compounds (PC) and anthocyanins (AC), and antioxidant activity (AOA) of grain of two purple-grained lines (163 and 193) and drought-resistant white-grained cultivar (cv.) Khazine of soft spring wheat (Triticum aestivum L.) in growing seasons of 2015-2018 years. It has been shown that the impact of drought and high temperatures on the wheat yield is complex and depends on genotype resistance, on the strength/duration of stress factor action, and on the stage of plant reproductive development. The periods of sensitivity were booting, heading, flowering, and milky ripening. In 2018, prolonged exposure to high temperatures and drought, from the stage of booting to the milky ripening stage, led to a decrease in the yield of all genotypes, and also contributed to an increase in the Kjeldahl protein content and the fraction of non-extractable proteins in the grain. In 2016, drought during the reproductive period and high temperatures at the stage of milk ripening turned out to be more favorable for the formation of the yield compared to the weather conditions in 2018, they contributed to an increase in the fraction of non-extractable proteins in Khazine grain, but a decrease in the content of non-extractable proteins in the grain of purple wheat lines. A decrease in the weight of 1000 grains under drought conditions was observed only for line 163. It was shown that purple wheat lines did not differ significantly from the cv. Khazine in the total PC content, but they had a higher AOA, probably due to presence of ACs. Drought caused a decreased PC and AC content in the grain of line 163, but an increased PC and AC content in line 193, which correlated with decreasing or increasing of AOA. It was shown that purple lines have different resistance to drought, which, can be explained by the ability to activate biosynthesis of PC and, particularly, ACs with high AOA in response to impact of stressors.