Change in grain size of promising lines and varieties of spring soft wheat

The purpose of research is to study the varietal variability of the grain size trait of spring soft wheat and to identify new promising lines of wheat with stable 1000 grain weight indicators. The studies were carried out in 2018-2022 on the basis of the Volga NIISS - a branch of the SamSRC RAS. The location of the field research is the forest-steppe conditions of the Samara Region. The object of research is 4 zoned varieties and 13 new promising lines of spring soft wheat of the competitive variety testing (CVT) of the Volga NIISS. The growing seasons of plants for the 2018-2022 studies took place in arid and at times severely arid conditions. The weight of 1000 grains of spring soft wheat varied on average over the years from 31.4 to 38.5 g. In 2019 and 2022 larger grains were formed compared to other years studied. Weather conditions 2019 and 2022 had a positive effect on grain filling and, accordingly, on the weight of 1000 grains. The largest grains were distinguished by: variety Kinelskaya 59 - 38.5 g; line Erythrospermum 4144 - 36.2; Erythrospermum 6517/24-1 - 36.0 g. The highest homeostaticity and the lowest intravarietal variability were observed in the Erythrospermum 6635/3 line (104.1 and 2.89 %, respectively); this line was less sensitive to changes in soil and climatic conditions. Also, high homeostaticity and low intravarietal variability in terms of “weight of 1000 seeds” were observed in the following varieties: Kinelskaya Niva, Kinelskaya 2010, Kinelskaya Yubileinyaya and line Erythrospermum 4144. Selected samples based on the trait “weight of 1000 grains” are recommended for inclusion in breeding crossbreeding programs.