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• 1. [Article] Transfer, characterization and mapping of white mold resistance in an advanced backcross interspecific population between Phaseolus vulgaris and Phaseolus coccineus

  The advanced backcross-quatitative trait loci (AB-QTL) breeding method was employed on snap bean (OR 91G x PI433251B) and dry bean (M0162 x PI433251B) interspecific populations to transfer resistance QTL ...

  Citation × Citation Citation Abstract Copy Title: Transfer, characterization and mapping of white mold resistance in an advanced backcross interspecific population between Phaseolus vulgaris and Phaseolus coccineus Author: Zimmerman, Shawna Jean The advanced backcross-quatitative trait loci (AB-QTL) breeding method was employed on snap bean (OR 91G x PI433251B) and dry bean (M0162 x PI433251B) interspecific populations to transfer resistance QTL from resistant donor parent Phaseolus coccineus into P. vulgaris. For OR 91G x PI433251B, analyses produced nine linkage groups corresponding to eight core linkage groups for P. vulgaris consisting of 40 markers covering 336.7 cM (approximately 28.1% of the estimated bean genome). MQM mapping revealed one QTL that was located on linkage group Pv05 (LOD of 3.2) associated with 2009 percent field severity and accounted for 6.4% of the phenotypic variation. For M0162 x PI433251B, three linkage groups were observed, corresponding to three core linkage groups for P. vulgaris and consisted of 11 markers covering 42.44 cM (approximately 3.5% of the estimated bean genome). One QTL was identified with MQM mapping on linkage group Pv02 with a LOD of 1.8 and associated with the 2009 percent field severity, and accounted for 9.8% of the phenotypic variation. Because many SSR markers with known locations on previously published common bean linkage maps were unlinked, we constructed virtual maps to order polymorphic SSRs. In conjunction with single factor analysis and the Kruskall-Wallis analysis, probable locations of QTL were identified in the absence of the traditional QTL mapping. In addition to QTL mapping, trends for interspecific populations were investigated by comparing three different populations: the two populations being reported in this document for the first time (OR 91G x PI433251B and M0162 x PI433251B) and the previously analyzed OR 91G x PI255956. The general trends for interspecific populations were severe segregation distortion attributed to overrepresentation of heterozygotes, low marker polymorphism and regions of the genome that appear to recombine infrequently. Title: Transfer, characterization and mapping of white mold resistance in an advanced backcross interspecific population between Phaseolus vulgaris and Phaseolus coccineus Author: Zimmerman, Shawna Jean The advanced backcross-quatitative trait loci (AB-QTL) breeding method was employed on snap bean (OR 91G x PI433251B) and dry bean (M0162 x PI433251B) interspecific populations to transfer resistance QTL from resistant donor parent Phaseolus coccineus into P. vulgaris. For OR 91G x PI433251B, analyses produced nine linkage groups corresponding to eight core linkage groups for P. vulgaris consisting of 40 markers covering 336.7 cM (approximately 28.1% of the estimated bean genome). MQM mapping revealed one QTL that was located on linkage group Pv05 (LOD of 3.2) associated with 2009 percent field severity and accounted for 6.4% of the phenotypic variation. For M0162 x PI433251B, three linkage groups were observed, corresponding to three core linkage groups for P. vulgaris and consisted of 11 markers covering 42.44 cM (approximately 3.5% of the estimated bean genome). One QTL was identified with MQM mapping on linkage group Pv02 with a LOD of 1.8 and associated with the 2009 percent field severity, and accounted for 9.8% of the phenotypic variation. Because many SSR markers with known locations on previously published common bean linkage maps were unlinked, we constructed virtual maps to order polymorphic SSRs. In conjunction with single factor analysis and the Kruskall-Wallis analysis, probable locations of QTL were identified in the absence of the traditional QTL mapping. In addition to QTL mapping, trends for interspecific populations were investigated by comparing three different populations: the two populations being reported in this document for the first time (OR 91G x PI433251B and M0162 x PI433251B) and the previously analyzed OR 91G x PI255956. The general trends for interspecific populations were severe segregation distortion attributed to overrepresentation of heterozygotes, low marker polymorphism and regions of the genome that appear to recombine infrequently. Close

• 2. [Article] Characterization of physiological resistance to white mold and search for molecular markers linked to resistance via advanced backcross QTL analysis in an interspecific cross between Phaseolus coccineus and P. vulgaris

  White mold, caused by Sclerotinia sclerotiorum (Lib.) de Bary, results in severe losses in the production of common bean, Phaseolus vulgaris, especially snap bean varieties. Advanced backcross QTL analysis ...

  Citation × Citation Citation Abstract Copy Title: Characterization of physiological resistance to white mold and search for molecular markers linked to resistance via advanced backcross QTL analysis in an interspecific cross between Phaseolus coccineus and P. vulgaris Author: Haggard, Jack Erron White mold, caused by Sclerotinia sclerotiorum (Lib.) de Bary, results in severe losses in the production of common bean, Phaseolus vulgaris, especially snap bean varieties. Advanced backcross QTL analysis was used to identify quantitative trait loci for resistance to white mold in an interspecific cross of P. vulgaris and P. coccineus and to select resistant, well-adapted germplasm for development of superior common bean cultivars. A population of 115 BC2F4 lines from a cross of snap bean cultivar OR 91G x runner bean accession PI 255956 was genotyped using amplified fragment length polymorphism (AFLP®) and simple sequence repeat (SSR) markers. Corresponding BC2F5 progeny were evaluated for resistance to white mold in a greenhouse straw test and for tolerance to oxalate in a laboratory test. BC2F6 lines were then tested for resistance under field conditions. Single factor analysis of variance identified 29 marker loci contributing to response in at least one phenotypic test. One QTL conditioning 6% of the variance for field resistance was identified by composite interval mapping on linkage group 09, anchored to the consensus linkage group b09 by SSR loci. Significant deviation from expected segregation ratios was observed at all but 3 SSR loci and at all but 7 AFLP® loci (p < 0.05). Codominant SSR markers revealed excessive heterozygosity, and an underrepresented donor homozygous marker class. Several SSR markers polymorphic between parents failed to segregate in the progeny, particularly those corresponding to bean core map linkage groups b01, b04, and b05. Several lines were identified as possessing resistance superior to the recurrent parent. These will be incorporated into our efforts to produce highly resistant snap bean varieties. Title: Characterization of physiological resistance to white mold and search for molecular markers linked to resistance via advanced backcross QTL analysis in an interspecific cross between Phaseolus coccineus and P. vulgaris Author: Haggard, Jack Erron White mold, caused by Sclerotinia sclerotiorum (Lib.) de Bary, results in severe losses in the production of common bean, Phaseolus vulgaris, especially snap bean varieties. Advanced backcross QTL analysis was used to identify quantitative trait loci for resistance to white mold in an interspecific cross of P. vulgaris and P. coccineus and to select resistant, well-adapted germplasm for development of superior common bean cultivars. A population of 115 BC2F4 lines from a cross of snap bean cultivar OR 91G x runner bean accession PI 255956 was genotyped using amplified fragment length polymorphism (AFLP®) and simple sequence repeat (SSR) markers. Corresponding BC2F5 progeny were evaluated for resistance to white mold in a greenhouse straw test and for tolerance to oxalate in a laboratory test. BC2F6 lines were then tested for resistance under field conditions. Single factor analysis of variance identified 29 marker loci contributing to response in at least one phenotypic test. One QTL conditioning 6% of the variance for field resistance was identified by composite interval mapping on linkage group 09, anchored to the consensus linkage group b09 by SSR loci. Significant deviation from expected segregation ratios was observed at all but 3 SSR loci and at all but 7 AFLP® loci (p < 0.05). Codominant SSR markers revealed excessive heterozygosity, and an underrepresented donor homozygous marker class. Several SSR markers polymorphic between parents failed to segregate in the progeny, particularly those corresponding to bean core map linkage groups b01, b04, and b05. Several lines were identified as possessing resistance superior to the recurrent parent. These will be incorporated into our efforts to produce highly resistant snap bean varieties. Close