Fine-mapping of a major QTL controlling angular leaf spot resistance in common bean (Phaseolus vulgaris L.)

Abstract

Key messageA major QTL for angular leaf spot resistance in the common bean accession G5686 was fine-mapped to a region containing 36 candidate genes. Markers have been developed for marker-assisted selection.AbstractCommon bean (Phaseolus vulgaris L.) is an important grain legume and an essential protein source for human nutrition in developing countries. Angular leaf spot (ALS) caused by the pathogen Pseudocercospora griseola (Sacc.) Crous and U. Braun is responsible for severe yield losses of up to 80 %. Breeding for resistant cultivars is the most ecological and economical means to control ALS and is particularly important for yield stability in low-input agriculture. Here, we report on a fine-mapping approach of a major quantitative trait locus (QTL) ALS4.1GS, UC for ALS resistance in a mapping population derived from the resistant genotype G5686 and the susceptible cultivar Sprite. 180 F3 individuals of the mapping population were evaluated for ALS resistance and genotyped with 22 markers distributed over 11 genome regions colocating with previously reported QTL for ALS resistance. Multiple QTL analysis identified three QTL regions, including one major QTL on chromosome Pv04 at 43.7 Mbp explaining over 75 % of the observed variation for ALS resistance. Additional evaluation of 153 F4, 89 BC1F2 and 139 F4/F5/BC1F3 descendants with markers in the region of the major QTL delimited the region to 418 kbp harboring 36 candidate genes. Among these, 11 serine/threonine protein kinases arranged in a repetitive array constitute promising candidate genes for controlling ALS resistance. Single nucleotide polymorphism markers cosegregating with the major QTL for ALS resistance have been developed and constitute the basis for marker-assisted introgression of ALS resistance into advanced breeding germplasm of common bean.Electronic supplementary materialThe online version of this article (doi:10.1007/s00122-015-2472-6) contains supplementary material, which is available to authorized users.

Prevalence of angular leaf spot disease and sources of resistance in common bean in eastern Democratic Republic of Congo

“…Variety G5686, also a documented source of resistance (Mahuku et al, 2009) on Pv10, identified in both G5686 (Keller et al, 2015) and CAL143 (Oblessuc et al (2012(Oblessuc et al ( , 2013 were officially named as Phg-4 and Phg-5 (Souza et al, 2015;).…”

Validation of QTL for resistance to Aphanomyces euteiches in different pea genetic backgrounds using near-isogenic lines

“…However, in some cases, after MAS the effect of a QTL was reduced or nullified. Subsequently, an increasing number of fine mapping studies of major-effect resistance QTL have been recently described (Keller et al 2015). For example, Ahmadi et al (2001) reported that MAS was particularly useful for validating epistatic effects between two QTL for resistance to rice yellow mottle virus, in introgression lines carrying both QTL compared to lines hosting only one of the two QTL which displayed no effects.…”

Alternative markers linked to the Phg-2 angular leaf spot resistance locus in common bean using the Phaseolus genes marker database

“…The PhaseolusGenes marker database has become an essential tool for cataloging bean marker diversity so that the breeding community can utilize marker information from multiple sources to facilitate MAS (Gonçalves-Vidigal et al, 2011Reinprecht et al, 2013;Oblessuc et al, 2013Oblessuc et al, , 2015Aranda et al, 2014;Keller et al, 2015;Sousa et al, 2015;Coimbra-Gonçalves et al, 2016;Perseguini et al, 2016). Because genomic resequencing of breeding parents is today a more routine practice with the lowered cost of sequencing, the PhaseolusGenes database should evolve from a marker database into a sequence database, which includes not only the current markers but also the increasingly large number (> 2,000) of genotypes that have been sequenced, including the 16 parental genotypes of the ABC projects (T. Miller and P. Gepts, unpubl.…”

“…Seven QTLs on five chromosomes were identified in a IAC-UNA × CAL 143 recombinant inbred population and named ALS2.1, ALS3.1, ALS4.1, ALS4.2, ALS5.1, ALS5.2 and ALS10.1 (Oblessuc et al, 2012(Oblessuc et al, , 2013(Oblessuc et al, , 2015. Additionally, three major R genes identified in Andean G5686 (Phg G5686A , Phg G5686B and Phg G5686C ) (Mahuku et al, 2009) were later treated as quantitative loci by Keller et al (2015) and mapped to the same loci as ALS4.1, ALS4.2 and ALS9.1 (Oblessuc et al, 2012;Keller et al, 2015).…”