A family of LRR sequences in the vicinity of the Co-2 locus for anthracnose resistance in Phaseolus vulgaris and its potential use in marker-assisted selection

Abstract

Molecular markers offer new opportunities for breeding for disease resistance. Resistance gene pyramiding in a single cultivar, as a strategy for durable resistance, can be facilitated by marker-assisted selection (MAS). A RAPD marker, ROH20(450), linked to the Mesoamerican Co-2 anthracnose resistance gene, was previously transformed into a SCAR marker, SCH20. In the present paper we have further characterized the relevance of the SCH20 SCAR marker in different genetic backgrounds. Since this SCAR marker was found to be useful mainly in the Andean gene pool, we identified a new PCR-based marker (SCAreoli) for indirect scoring of the presence of the Co-2 gene. The SCAreoli SCAR marker is polymorphic in the Mesoamerican as well as in the Andean gene pool and should be useful in MAS. We also report that PvH20, the cloned sequence corresponding to the 450-bp RAPD marker ROH20(450), contains six imperfect leucine-rich repeats, and reveals a family of related sequences in the vicinity of the Co-2 locus. These results are discussed in the context of the recent cloning of some plant resistance genes.

Molecular Analysis of a Large Subtelomeric Nucleotide-Binding-Site–Leucine-Rich-Repeat Family in Two Representative Genotypes of the Major Gene Pools of Phaseolus vulgaris

“…The molecular weight standards were l concatemers designed for use as size markers for PFGE (New England Biolabs). DNA transfer, hybridization conditions, and probe preparation were done as described in Geffroy et al (1998). PRLJ1 is a NBS probe encompassing the P-loop-hydrophobic domain (HD) region of the NBS-LRR family specific to the B4 R gene cluster .…”

A reference genome for common bean and genome-wide analysis of dual domestications

“…16). In particular, three large clusters were located at the ends of chromosomes Pv04, Pv10 and Pv11 and contained more than 40 NL genes that were enriched for CNL (Pv04 and Pv11) or TNL (Pv10) genes that colocalized with previously mapped genes related to disease resistance [16][17][18][19][20][21] . Local tandem duplications and ectopic recombination between clusters are involved in the evolution of these NL gene clusters 22 .…”

Breeding of Common Bean for Resistance to the Physiological Races of Anthracnose Identified in Bulgaria

“…PcR analyses for presence of Co-2 and Co-4 genes in selected lines using ScAR markers were performed (7,14,18). two ScAR markers linked to Co-2 gene were used: ScAreoli (5'-GGG AGA cAt ccA tcA GAc AAc tcc-3' and 5'-GtA tcc Att tGA AGG AGc t-3') and Sq4 (5'-cct tAG GtA tGG tGG GAA AcG A-3' and 5'-tGA GGG cGA GGA ttt cAG cAA Gtt-3').…”