Impact of Alien Genes on Disease Resistance, Drought Tolerance, and Agronomic Traits in Winter Wheat Commercial Varieties

Abstract

Background: Global climate change facilitates the spread of diseases of the winter bread wheat (Triticum aestivum L.) and increases the yield losses caused by a combination of these diseases and drought. Prevention of the yield losses depends on the identification of the resistance genes and the introduction of these genes into commercial cultivars. Objective: The objective of the study was to evaluate resistance to widespread diseases, drought and other agricultural traits amongst the members of diversity panel consisting of introgression wheat lines derived from complex interspecies crosses. Materials and Methods: The field trials were conducted during 2018-2019 and 2019-2020 seasons. The winter wheat diversity panel consists of seventy-eight introgression lines and two check cultivars developed for the arid climate zone of southern Ukraine. The data on nine agronomic (quantitative scores) and five-pathogen response (point scores) traits were collected and subjected to both variance and correlation analysis to determine the contribution of the individual genetic backgrounds towards plant resiliency. Results: Most lines were found resistant to rust species. The distribution of responses in the analyzed lines was bimodal in response to rusts and unimodal in response to powdery mildew or septoria. The resistance traits showed no correlation with heading date, plant height, and protein content. The yield traits did not correlate with the resistance to diseases except for stem rust (Rsp = 0.34**) and Septoria blight (Rsp = −0.23*). A negative correlation was observed between quality traits and grain yield, but quality traits correlated positively with each other. Conclusion: High diseases resistance trait correlates with low yield, reduced protein content or small grain. The frequency of lines combining pathogen resistance as measured by total yield with grain quality is low. The introgression lines provide a source of genes for improving disease and drought resistance of winter wheat.