Submitted to: Crop Protection Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/25/2010
Publication Date: 5/1/2011
Citation: Prom, L.K., Isakeit, T., Perumal, R., Erpelding, J.E., Rooney, W.L., Magill, C.W. 2011. Evaluation of the Ugandan sorghum accessions for grain mold and anthracnose resistance. Crop Protection Journal. 30(5):566-571. Interpretive Summary: Worldwide, grain mold and anthracnose are two of the most important diseases of sorghum. Yield losses from these fungal diseases can reach 100% when susceptible lines are planted. The best means for controlling these diseases is by planting resistant lines. In this study, sorghum accessions from Uganda were screened in 2005 and 2006 against the anthracnose pathogen and several grain molding fungi in order to identify resistant sources. Accession PI534117 had very low grain mold infection, while accessions PI534117, PI534144, PI576337, PI297199, PI533833, and PI297210 were highly resistant to anthracnose in both years. The accession PI534117 had low levels of grain mold infection and also was highly resistant to anthracnose. This suggests that this line may be useful in breeding programs to develop grain mold and anthracnose resistance lines/hybrids which will increase productivity and profitability of sorghum.
Technical Abstract: Sorghum accessions from Uganda were evaluated for grain mold and anthracnose resistance during the 2005 and 2006 growing seasons at the Texas A&M University Research Farm, near College Station, TX. Accession PI534117 and SC719-11E exhibited the lowest grain mold severities of 2.4, whereas, accessions PI534117, PI534144, PI576337, PI297199, PI533833, and PI297210, with SC748-5 were highly resistant to anthracnose in both years. Accessions PI534117, PI297134, PI297156 exhibited low grain mold severities in 2006. Significant negative correlation was recorded between grain mold and percent germination and high temperature in both years. In 2006, daily precipitation recorded significant positive correlation with grain mold. The seed mycoflora was analyzed across sorghum lines and treatments. In 2005, Curvularia lunata and Fusarium thapsinum were the most frequently recovered fungal species with 31 and 21 % incidence, respectively, followed by Alternaria spp. (19%) and F. semitectum (13%). In 2006, predominant colonizers were F. thapsinum (58%), followed by Alternaria and F. semitectum with 15 and 10, percent respectively, while C. lunata had a 6% incidence. In this study, PI534117 holds promise for multiple disease resistance, as it had the lowest disease severity of grain mold and was highly resistant to anthracnose in both years. It also has a high germination rate, a high seed weight, and its short stature is more advantageous for the new A-line conversion program.