qRgls1.06, a major QTL conferring resistance to gray leaf spot disease in maize

Gray leaf spot (GLS) caused by Cercospora zeae-maydis and C. zeina is an extremely devastating leaf disease that limits maize production annually. The use of GLS-resistant maize hybrids is the most cost-effective approach for reducing losses. Resistance to GLS is quantitatively inherited in maize (Zea mays L.) and further sources of resistance remain to be analyzed. Here, we detected gRgls1.06, a major quantitative trait locus for GLS resistance in bin 1.06 that explained approximately 55% of the phenotype variance. Fine mapping over 2 consecutive years localized gRgls1.06 to a 2.38-Mb region. Homozygous gRgls1.06(WGR/WGR) plants in DZO1 background displayed higher GLS resistance and 100-grain weight than DZO1 plants. The GLS responses of several susceptible elite inbred lines were improved by the introduction of gRgls1.06 by marker-assisted backcrossing. Our findings extend the understanding of the genetic basis of resistance to GLS and provide a set of resistant germplasm for genetic improvement of resistance to GLS in maize. (C) 2020 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.

Automated summary

Gray leaf spot (GLS) is a devastating leaf disease in maize caused by Cercospora zeae-maydis and C. zeina, and introducing resistant genes can significantly improve resistance, offering an effective strategy for disease control.