Changes in yield and its structure elements of winter bread wheat depending on the conditions of a moisture supply and a genotype

Abstract

Relevance. In this regard, it is of great relevance to study influence of individual arid situations on the yield and its structure elements for winter bread wheat varieties; to identify more reliable selection criteria in breeding for drought resistance; to determine differences in the drought conditions’ response among genotypes with contrasting length of a vegetation period.Methods. The study was carried out in 2017–2021 on the fields of the research crop rotation of the FSBSI «ARC “Donskoy”», according to a green manure fallow due to the methods of SVT and a field trial. The objects of the research were 25 modern varieties and promising breeding lines of our own breeding.Results. There have been considered the types of droughts and their influence on the yield and its structural elements through the years of research in comparison with the control year 2017, which was favorable in precipitation and temperature conditions in all vegetation and development periods of winter wheat with HThC = 0.92–1.46. The yield decrease amounted to 39.4% in 2019 vs. 2017 and was due to a decrease in the number of sprouted plants and productive heads on 50.5% and 37.2%. In 2020, the productivity reduced on 10.7% due to head and plant productivity decrease on 31.8% and 12.1% and a grain size on 21.0%. In 2021, the yield decreased on 18.6% due to a decrease in plant density and productive head stand on 41.7% and 18.6%, and 1000-grain weight on 15.0%. Based on the correlation analysis, there have been identified the structural elements which could make the main contribution to productivity formation depending on the type of drought, namely plant density (r = 0.78), productive head (r = 0.70), grain size of a head and a plant (r = 0.60 and r = 0.79), plant height (r = 0.70).