QTL Mapping for Adult-Plant Resistance to Leaf Rust in Italian Wheat Cultivar Libellula.

Wheat leaf rust (), which is caused by Eriks. (), is one of the most important wheat diseases affecting wheat production globally. Using resistant wheat cultivars is the most economical and environmentally friendly way to control leaf rust. The Italian wheat cultivar Libellula has demonstrated good resistance to in field studies. To identify the genetic basis of resistance in 'Libellula', 248 F recombinant inbred lines from the cross 'Libellula'/'Huixianhong' was phenotyped for severity in seven environments: the 2014/2015, 2016/2017, 2017/2018, and 2018/2019 cropping seasons at Baoding, Hebei Province, and the 2016/2017, 2017/2018, and 2018/2019 crop seasons at Zhoukou, Henan Province. Bulked segregant analysis and simple sequence repeat markers were then used to identify the quantitative trait loci (QTLs) for adult-plant resistance in the population. Six QTLs were consequently detected and designated as and that were presumed to be new and , , , and that were identified at similar physical positions as previously reported QTLs. Based on chromosome positions and molecular marker tests, and share similar flanking markers with and , respectively. and are race nonspecific adult plant resistance (APR) genes for leaf rust and stripe rust and powdery mildew. showed multiple disease resistance to leaf rust, stripe rust, Fusarium head blight, and powdery mildew. The QTL identified in this study, as well as their closely linked markers, may potentially be used in marker-assisted selection in wheat breeding.