Correlations between the protein content in grain with economic characters in winter bread wheat breeding accessions of hybrid origin on irrigation

Abstract

Purpose and Objectives. To evaluate the expression of the "protein content in grain" trait in winter bread wheat lines derived from late-ripening accessions of the Western European ecotype; to construct correlation-regression models for the relationships of the protein content in grain with the "anthesis - grain ripeness" interphase period length and grain yield in elite accessions grown in breeding nurseries.
 Material and Methods. The field studies were carried out at the Institute of Irrigated Agriculture of NAAS in 2019–2021. Modern winter wheat varieties bred at the Institute, collection specimens of the Western European ecotype, which had been introduced from France (registration numbers Kf1...16), and their hybrids were studied. Individual selections of elite plants from F2 were brought to the control nursery and evaluated for protein content in grain, yield, "anthesis - ripeness" period and other economic characteristics. Biometric measurements, biochemical analyses, and yield records were conducted by traditional methods. The study methods were field, laboratory, biochemical, breeding-genetic, and statistical. The studies were carried out under irrigation conditions at the pre-irrigation field moisture capacity (FMC) in the 0–50 cm soil layer of 75%.
 Results and Discussion. The expression of the "protein content in grain" trait in the breeding accessions selected from hybrid populations, which had been originated from Western European ecotypes of winter bread wheat, was analyzed; the correlation-regression models of the relationships between the protein content in grain, the grain yield and the "anthesis - ripeness" period were constructed. The “anthesis – ripeness” period in the best accessions lasted 45 - 52 days, and each original hybrid combination had its own optimum, which was associated with a high yield and protein content in grain. Extension of the "anthesis - ripeness" period slightly increased the grain yields of the breeding accessions from some hybrid populations; however, analogous effect on the protein content in grain was insignificant.
 Conclusions. A concurrent increase in the grain yield and protein content in grain through traditional selections is possible; however, such parallel enhancement of these traits is more suitable for heterogeneous hybrid populations with low protein contents grain and yields, or with low values of one of these traits (low protein content). For each hybrid population from parents contrasting in vegetation length, it is necessary to develop a specific plan of selections with due account for intra-population correlation-regression models of yield capacity, protein content in grain and “anthesis – ripeness” period length.