Black dry bean (Phaseolus vulgaris L.) germplasm accessions with resistance to prevalent races of Colletotrichum lindemuthianum in Canada
Sandhu, K., Conner, R.L., Balasubramanian, P., Hou, A. (2017). Black dry bean (Phaseolus vulgaris L.) germplasm accessions with resistance to prevalent races of Colletotrichum lindemuthianum in Canada. Canadian Journal of Plant Science, [online] 98(1), 17-27. http://dx.doi.org/10.1139/cjps-2016-0405
Plain language summary
Dry edible bean is an important cash and rotation crop in western Canada. Anthracnose is one of the major diseases reducing yield and seed quality in dry bean commercial production. In Manitoba, dry bean cultivars, especially in black beans, generally lack the resistance to anthracnose disease, and breeding materials for the creation of crop cultivars resistant to anthracnose are limited in Canada. One hundred and fifty-five black bean germplasm materials originating from twenty countries were evaluated in this study for their resistance to the major pathogen races in western Canada. Artificial inoculation with the pathogens identified 40 lines that were resistant to one or multiple races of the anthracnose pathogen. The selected resistant lines were also screened with molecular markers closely associated with five known anthracnose resistance genes. The majority of resistant lines appeared to carry at least one or two major resistance genes. The black bean lines with anthracnose resistance will provide much-needed breeding materials and expand genetic diversity for Canadian and international dry bean improvement.
Genetic diversity of dry bean (Phaseolus vulgaris L.) in Canadian breeding programs is low. Cultivars, especially black beans, generally lack resistance to anthracnose. One hundred and fifty-five black bean accessions originating from twenty countries were evaluated for their resistance to races 73 and 105 of Colletotrichum lindemuthianum (Sacc. & Magnus) Briosi & Cavara, the predominant races of the bean anthracnose pathogen in Canada. Artificial inoculation in growth chambers identified 39 accessions that were resistant to race 73, of which 33 were also resistant to race 105. Only one accession was susceptible to race 73 and resistant to 105. The resistant lines from the collection were also screened with genetic markers closely associated with known anthracnose resistance genes. At least one of the major resistance loci, Co-1, Co-2, Co-3, Co-4, and Co-5, was indicated to be present in all except four accessions. The majority of resistant accessions appeared to carry at least one or two major resistance loci. The black bean accessions with anthracnose resistance will provide much-needed breedingmaterials and expand genetic diversity for Canadian and international dry bean improvement.