Disease resistance and adaptation of winter wheat lines derived from wide hybridisation under arid environments

Abstract

A combination of fungal diseases and drought can cause significant yield losses of winter wheat (Triticum aestivum L.). It is known that alien traits introduced through wide hybridisation contribute to breeding of cultivars with a higher yield potential in arid environments. In this study, the impact of alien genes on the main agronomic traits in the arid environments of the Southern Steppe of Ukraine was analysed. The lines were grown under the arid conditions in 5 and 10 m 2 plots in the 2019-2021 growing seasons. Eight agronomic and six plant pathological traits were assessed and subjected to statistical analysis to comprehend the diversity and connections between the features. Due to the successful introgression of alien genes from all sources involved in hybridisation, most of lines were resistant to one of the rust species. The lines derived from the genotype containing the translocation 1BL.1RS in the karyotype and Triticum timopheevii in the pedigree were resistant to all rust species. There was a negative correlation between the protein content and grain yield in 2020 (r = −0.40***), and a weak positive correlation was found between the grain yield and resistance to yellow rust (R sp = 0.19* in 2019 and R sp = 0.26*** in 2020) or tolerance to Septoria leaf blotch (R sp = 0.27***). Under drought conditions, the grain yield reduced by 32.5% in 2020 and ca. 70% in 2021. The lines containing alien genes Lr42 and Hs showed a higher grain yield than the recurrent and standard ones. For further breeding, eighteen lines with a high TKW, protein content, and grain yield, and resistance to drought or disease were identified, and four promising drought-tolerant lines have been selected.