Rivera, Yazmín

Profile Picture

Filters

20061
Reset filters

Settings

Citations

Publication Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Publication
    Variation for Anthracnose (Colletotrichum sublineolum) resistance within the Sorghum [Sorghum bicolor (L.) Moench] germ plasm collection from the Kayes region of Mali, West Africa
    (2006) Rivera, Yazmín; Beaver, James S.; College of Agricultural Sciences; Rivera, Lydia I.; Erpelding, John E.; Muñoz, Miguel A.; Department of Agricultural and Biosystems Engineering; Kolterman, Durante A.
    Anthracnose, caused by Colletotrichum sublineolum, is considered one of the most important diseases of sorghum. The pathogen is highly variable; therefore, additional sources of host plant resistance are needed for the development of anthracnose resistant hybrids to prevent crop losses. West African countries such as Mali may provide new sources of resistance. Environmental conditions in the region are favorable for the pathogen, which could contribute to selection of host plant resistance in sorghum landraces. The objectives of this research were to evaluate the variation in disease response to anthracnose infection and to identify stable sources of resistance within the sorghum germplasm collection from the Kayes region of Mali. During 2003 (wet season) and 2004 (dry season) anthracnose evaluations were conducted at the USDAARS-TARS at Isabela, Puerto Rico. From 277 accessions evaluated, a resistant response was observed for 140 accessions in the wet season and 131 accessions in the dry season. Stable resistance over seasons was observed for 120 accessions. Association between anthracnose disease response and sorghum germplasm phenotypic characteristics and climatic conditions in the country of origin were also evaluated to determine if resistance was influenced by these factors. Significant differences were observed between the anthracnose disease response within administrative districts of the Kayes region of Mali and for rainfall pattern, indicating that disease response of the germplasm accessions varied from north to south. More accessions were resistant in the south as compared to the north. We assume that this is due to the rainfall pattern present in the region contributing to greater selection pressure under the wetter conditions of the south. Significant differences were also observed between disease response and sorghum races grown in the region. We assume that these differences in disease response were due to race durra commonly grown in drier regions whereas race guinea is more associated with wetter regions. Plant color and rust disease response were not associated with anthracnose disease response. The response of rust, caused by Puccinia purpurea, was not influenced by the climatic conditions present in the Kayes region of Mali, as compared to anthracnose response. Since rainfall pattern in the Kayes region was associated with anthracnose disease response, this would indicate that environmental conditions such as annual rainfall pattern could be used to help identify germplasm collections that may contain new sources of anthracnose resistance. Approximately 50% of the sorghum accessions from the Kayes region showed a resistant disease response, suggesting that the sorghum germplasm collection from Mali would be a valuable source of anthracnose resistance for sorghum improvement.