Common Bean Landrace Jalo Listras Pretas Is the Source of a New Andean Anthracnose Resistance Gene

摘要

Novel sources of resistance are continuously needed to combat anthracnose disease in common bean (Phaseolus vulgaris L.) caused by the hypervariable pathogen Colletotrichum lindemuthianum (Sacc. and Magnus) Briosi and Cavara. We sought to characterize the novel anthracnose resistance in Andean common bean landrace 'Jalo Listras Pretas' (JLP). Jalo Listras Pretas is resistant to races 9, 64, 65, and 73 of the anthracnose pathogen used in this study. To examine inheritance of anthracnose resistance in JLP, F2 populations JLP/Mexico 222 and JLP/Cornell 49242 were inoculated with discriminating races of the pathogen. Segregation for resistance in both F2 populations fit a 3:1 resistant/susceptible ratio suggesting that the anthracnose resistance in JLP is controlled by a single dominant gene. To establish independence of the resistance gene in JLP from other published resistance genes, allelism tests were conducted with 14 F2 populations derived from crossing JLP with Andean cultivars carrying anthracnose resistance genes Co-1, Co-12, Co-13, Co-15, and Co-12, and with Middle American cultivars with Co-2, Co-3, Co-43, Co-5, Co-6, Co-7, Co-9, Co-10, and Co-11. Results revealed the resistance gene in JLP was independent of the Andean loci Co-1 and Co-12, and the nine Middle American anthracnose resistance genes. The symbol Co-13 was assigned to this newly discovered anthracnose resistance gene in Brazilian Andean common bean landrace JLP.