CRUDE PROTEIN CONTENT IN GRAIN OF SPRING BARLEY VARIETIES

The aim of the research is the formation of crude protein in the grain of spring barley varieties cultivated in the conditions of the Predkamsk zone of the republic of Tatarstan in 2016-2023. Correlation analysis revealed a reliable at 1% significance level dependence of crude protein content in grain on hydrothermal indicators of interphase periods "sprouting - sprinkling", "sprinkling - full ripeness" and the growing season: positive average from the average daily air temperature r=0.39/0.67/0.68; negative average and strong from the sum of precipitation r=-0.55/- 0.47/-0.71 and from the hydrothermal coefficient (HTC) index r=-0.55/-0.47/-0.74, respectively. The article presents the varietal mean values of crude protein content of grain as a function of the year of study. Significantly high varietal mean value of this index was observed in 2021 under extreme drought conditions (14.84%,) and significantly low value was observed in 2017 under wet conditions (10.92%). The average varietal difference in the crude protein content of grain in contrasting conditions of the growing period amounted to 3.92%. The share of the influence of year on the crude protein content in the grain of spring barley varieties amounted to 68.4%. In the varietal section, reliably high average values of crude protein content in grain were characterized by varieties Raushan, Nur and Laishevsky (13.73/13.61/13.55%, respectively), reliably low - Endan variety (12.63%). The coefficient of variation of crude protein content in grain of spring barley varieties varied from 5.5% in Endan variety to 17.8% in Nur variety. The trend line of crude protein content in the grain of Endan variety was at the same level, while the line of crude protein content in the grain of Noor variety was in an upward trend depending on the change in HTC indices of vegetation periods. Thus, inter-variety differences in response to changes in HTC indices of the vegetation period were established.