Assessment of sorghum germplasm from Burkina Faso and South Africa to identify new sources of resistance to grain mold and anthracnose

摘要

Sorghum is an important worldwide crop whose yield can be significantly reduced by anthracnose (Colletotrichum sublineola) and grain mold diseases (multiple fungi). The identification of new genetic sources of resistance to both diseases is imperative for the development of new sorghum varieties. To this end, a total of 80 exotic germplasm accessions from Burkina Faso (BFA) and South Africa (ZAF) were evaluated for anthracnose and grain mold resistance during two planting periods in 2012 at the USDA-ARS experimental farms in Isabela, Puerto Rico. Twelve accessions were resistant to anthracnose during both evaluations of which 10 are originally from BFA. The anthracnose resistant accessions identified herein had a hypersensitive reaction characterized by lesions having red and purple color. Likewise, 9 accessions exhibited grain mold resistance after being inoculated with a mixture of a conidial suspension of Fusarium thapsinum, Fusarium semitectum, and Curvularia lunata during both periods. Eight of these accessions (PI 586182, PI 586186, PI 647705, PI 647706, PI 647707, PI 647708, PI 647710, and PI 647712) originated from BFA, while one (PI 61666) is from ZAF. The PI 586186 was the only accession that exhibited resistance to both anthracnose and grain mold. The grain mold resistant accession PI 61666 has a panicle shape that resembles a standard United States commercial type sorghum and is also photoperiod insensitive. The results presented herein indicate that the BFA germplasm could be an important source for anthracnose and grain mold resistance genes. The integration of these anthracnose and grain mold resistant germplasm into sorghum breeding programs should aid in expanding the genetic diversity and in the development of new resistant varieties. Published by Elsevier Ltd.