Submitted to: Revista Mexicana de Fitopatologia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/1/2007
Publication Date: 6/1/2007
Citation: Pecina-Quintero, V., Montes-Garcia, N., Williams-Alanis, H., Hernandez-Delgado, S., Mayek-Perez, N., Prom, L.K. 2007. Diversidad genetica de aislamientos de cornezuelo (Claviceps africana Fredrickson, Mantle, y de Milliano) de sorgo [Sorghum bicolor (L.) Moench] en Mexico. Revista Mexicana de Fitopatologia. 25(001):43-47. Interpretive Summary: Sorghum ergot can cause serious problems in most years in Mexico, especially in the central part of the country. In this study, differences in the ability of the fungal pathogen isolates to cause disease in several sorghum lines and to determine whether isolates of fungus collected from different areas were the same were conducted. The sorghum lines responded differently when treated with the ergot isolates; the work also showed that three strains of the ergot pathogen exist in areas of Mexico where isolates were collected. The results suggest that in these locations, breeders and farmers should select lines with high tolerance to the type of ergot pathogen that exists in the area to reduce the impact of the disease.
Technical Abstract: This study was conducted in Rio Bravo, Tamaulipas, and Celaya, Guanajuato, Mexico, in which pathogenicity of two isolates of ergot (Claviceps africana) obtained from the same two locations, were evaluated on six hybrids and three male sterile sorghum lines. Also, a genetic variance indicated significant differences between isolates for pathogenicity (evaluated as the floral infection percentage in sorghum genotypes), differences between genotypes, locations, planting dates, and years. The genetic analysis showed a great genetic intrapopulation variation (60% genetic diversity) and the occurrence of different ergot genotypes; nevertheless, there was a high genetic similarity (>94%) by the clonal character. In general, three groups of ergot genotypes are affecting sorghum in Mexico, one in the Bajio area (Guanajuato and Jalisco), another in Tamaulipas, and the third in Sinaloa.