Control of anthracnose disease (Colletotrichum lindemuthianum) of navy bean (Phaseolus vulgaris)

Se discute la aplicacion de un programa de control integrado de la antracnosis en frijol blanco en el sur de Ontario, Canada. Los procedimientos constaron del tratamiento de la semilla, inspeccion de semilla con pedigree, rotacion de 3 anos y un programa de mejoramiento genetico por retrocruzamiento. Se desarrollo y registro una formulacion para el tratamiento de la semilla: DCT (diazinon 6 por ciento, captan 18 por ciento y tiofanato 14 por ciento). Los tratamientos de la semilla suministraron proteccion adicional a todas las semillas con pedigree que fueron totalmente inspeccionadas para asegurar cero infeccion por antracnosis en el campo. Posteriormente se encontro que la rotacion de 3 anos era innecesaria, ya que la investigacion epidemiologica demostro la incapacidad del hongo para invernar en Ontario. La enfermedad logro controlarse en 1981, ano en el cual no se detecto antracnosis. En 1977 tambien se inicio un programa de mejoramiento genetico por retrocruzamientos para transferir el gene ARE, un gene que confiere resistencia a las razas alfa, beta, gamma, delta, lambda y epsilon, a todos los frijoles blancos recomendados en Ontario. En 1984 se liberaron los cv. resistentes Harofleet, Harokent, OAC Seaforth y OAC Rico y la enfermedad se controlo en su totalidad. (RA-CIAT) spa

The application of an integrated control program to control anthracnose in navy beans in southern Ontario, Canada, is discussed. Procedures consisted of seed treatment, pedigreed seed inspection, a 3-yr rotation, and a backcross breeding program. A seed treatment formulation, DCT (diazinon 6 percent, captan 18 percent, and thiophanate 14 percent), was developed and registered. Seed treatments provided added insurance to all the pedigreed seeds that were thoroughly inspected, to ensure zero anthracnose infection in the field. The 3-yr rotation was later found to be unnecessary, because an epidemiological investigation showed the inability of the fungus to overwinter in Ontario. The disease was brought under control by 1981, at which time no anthracnose was found. A backcross breeding program was also instituted in 1977 to transfer the ARE gene, a gene that confers resistance to the alpha, beta, gamma, delta, lambda, and epsilon races, to all recommended Ontario navy beans. In 1984, resistant cv. Harofleet, Harokent, OAC Seaforth, and OAC Rico were released and the disease was completely controlled. (AS) eng