Identification of RppSLN from an Elite Landrace: A Major Locus Conferring Resistance to Southern Corn Rust in Maize (Zea mays L.)

Yufei Wang; Shuai Ma; Dengfeng Zhang; Chunhui Li; Lin Chen; Bin Tang; Yixin An; Xuyang Liu; Guanhua He; Yunsu Shi; Yu Li; Tianyu Wang; Deguang Yang; Yongxiang Li

doi:10.3390/plants13223227

Identification of RppSLN from an Elite Landrace: A Major Locus Conferring Resistance to Southern Corn Rust in Maize (Zea mays L.)

Plants (Basel). 2024 Nov 16;13(22):3227. doi: 10.3390/plants13223227.

Authors

Yufei Wang^{1

2}, Shuai Ma^{2

3}, Dengfeng Zhang², Chunhui Li², Lin Chen², Bin Tang², Yixin An², Xuyang Liu², Guanhua He², Yunsu Shi², Yu Li², Tianyu Wang², Deguang Yang¹, Yongxiang Li²

Affiliations

¹ College of Agriculture, Northeast Agricultural University, Harbin 150006, China.
² State Key Laboratory of Crop Gene Resources and Breeding, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
³ Institute of Grassland, Flowers and Ecology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.

Abstract

Southern corn rust (SCR) is one of the most destructive foliar diseases in maize (Zea mays L.), resulting in significant yield losses. Therefore, the continuous identification of disease-resistant germplasm and the deployment of resistant hybrids is essential for durably controlling SCR. The objective of this research was to identify and characterize resistance loci against SCR in maize to expand disease management strategies. Here, we identified a maize landrace with high resistance to SCR 'Silunuo' (SLN) approaching complete immunity. We backcrossed it with a susceptible inbred line, N531, to generate a stable SCR-resistant introgression line N531_R. By crossing it with F35 (a susceptible inbred line), we created a large F₂ segregating population and mapped a major SCR-resistant locus on chromosome 10, known as RppSLN. Based on the genome assembly and annotation, we found that RppSLN harbors two NBS-LRR (nucleotide binding site-leucine-rich repeat) genes, namely Zmays10G000430 and Zmays10G000440. These NBS-LRR genes were significantly induced during artificial inoculation with Puccinia polysora, suggesting that they might be candidate genes collectively contributing to the resistance level at this locus. In conclusion, this study identified a major SCR resistance locus directly isolated from a landrace, providing valuable support and information for expanding new disease-resistant germplasms and promoting the utilization of landraces.

Keywords: RppSLN; landrace; maize (Zea mays L.); southern corn rust.

Grants and funding

This research was funded by the National Key Research and Development Program of China (2021YFD1200700) and the Agricultural Science and Technology Innovation Program, China (ASTIP).