Reaction to rust by a subset of sorghum accessions from Zimbabwe

Abstract

Sorghum rust is a common disease in most of the sorghum-growing areas of the world, which increase susceptibility to other major diseases. Although, plant resistance is the best control strategy, today, a limited number of resistance sources are available. Therefore, identification of new resistance sources is essential to extend the control of the disease. In this study 68 sorghum accessions from the Zimbabwe collection maintained by the USDA-ARS, Plant Genetic Resources Conservation Unit at Griffin, Georgia were evaluated in Isabela, Puerto Rico during two planting seasons in 2011 to identify new sources of rust resistance. Across the two growing seasons, 12 accessions showed resistance, 15 accessions exhibited a moderately susceptible response and 41 accessions showed a susceptible response. Variation in disease response was observed within and between experiments for 37 accessions. No rust infection was detected on PI482787 across the two growing seasons, while accession PI482795 exhibited the highest rust infection. This study identified new sources of rust resistance and shows that PI482787 possess gene(s) for rust resistance and that this accession could be used in sorghum improvement breeding programs. © 2012 Academic Journals Inc.