Open AccessMapping of partial resistance to Phytophthora sojae in soybean PIs using whole‐genome sequencing reveals a major QTL
Author(s) -
de Ronne Maxime,
Santhanam Parthasarathy,
Cinget Benjamin,
Labbé Caroline,
Lebreton Amandine,
Ye Heng,
Vuong Tri D.,
Hu Haifei,
Valliyodan Babu,
Edwards David,
Nguyen Henry T.,
Belzile François,
Bélanger Richard
Publication year - 2022
Publication title -
the plant genome
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 41
ISSN - 1940-3372
DOI - 10.1002/tpg2.20184
Subject(s) - quantitative trait locus , biology , phytophthora sojae , genetics , single nucleotide polymorphism , genotyping , allele , candidate gene , gene , genome wide association study , genotype
In the last decade, more than 70 quantitative trait loci (QTL) related to soybean [ Glycine max (L.) Merr.] partial resistance (PR) against Phytophthora sojae have been identified by genome‐wide association studies (GWAS). However, most of them have either a minor effect on the resistance level or are specific to a single phenotypic variable or one isolate, thereby limiting their use in breeding programs. In this study, we have used an analytical approach combining (a) the phenotypic characterization of a diverse panel of 357 soybean accessions for resistance to P. sojae captured through a single variable, corrected dry weight; (b) a new hydroponic assay allowing the inoculation of a combination of P. sojae isolates covering the spectrum of commercially relevant Rps genes; and (c) exhaustive genotyping through whole‐genome resequencing (WGS). This led to the identification of a novel P. sojae resistance QTL with a relatively major effect compared with the previously reported QTL. The QTL interval, spanning ∼500 kb on chromosome (Chr) 15, does not colocalize with previously reported QTL for P. sojae resistance. Plants carrying the favorable allele at this QTL were 60% more resistant. Eight genes were found to reside in the linkage disequilibrium (LD) block containing the peak single‐nucleotide polymorphism (SNP) including Glyma.15G217100 , which encodes a major latex protein (MLP)‐like protein, with a functional annotation related to pathogen resistance. Expression analysis of Glyma.15G217100 indicated that it was nearly eight times more highly expressed in a group of plant introductions (PIs) carrying the resistant ( R ) allele compared with those carrying the susceptible ( S ) allele within a short period after inoculation. These results offer new and valuable options to develop improved soybean cultivars with broad resistance to P. sojae through marker‐assisted selection.