Mapping maize chlorotic mottle virus tolerance loci in the Maize 282 Association Panel

Abstract

AbstractMaize lethal necrosis (MLN) is a devastating synergistic viral disease of maize caused by maize chlorotic mottle virus (MCMV) plus a virus in the Potyviridae family. The disease has severely impacted maize production in East Africa, Asia, and South America over the past decade, and the presence of MCMV and maize infecting potyviruses in the United States is an ongoing concern. In this study, we performed a genome‐wide association study (GWAS) using the Maize 282 Association Mapping Panel (AMP) to characterize the genetic architecture of host response to MCMV and to identify disease‐tolerant lines. The GWAS analysis detected genomic variants on chromosomes 3, 4, 5, and 8 that were significantly associated with response to MCMV. Several lines in the 282 AMP were highly tolerant to infection, including CML333, one of the parental lines used in the maize nested association mapping population. Quantitative trait locus analysis of the B73 × CML333 recombinant inbred line population revealed an MCMV tolerance locus on chromosome 10. These findings further our understanding of the genetic architecture of MCMV tolerance and will facilitate the development of maize lines, hybrids, and cultivars with improved resistance to MLN and MCMV.