Genetic Variation for Striga hermonthica Resistance and Yield Among Sorghum Accessions in Nigeria

Striga hermonthica (Delile) Benth., commonly referred to as witch weed, is a major constraint to sorghum (Sorghum bicolor (L.) Moench) production in the Northern region of Nigeria because of high yield losses due to infestation. To identify parental lines useful in breeding for S. hermonthica resistant sorghum genotypes adapted to Nigeria, twenty-five sorghum accessions were evaluated in Nigeria across three test environments. Both phenotypic and genetic components influenced the variation observed in the sorghum accessions. The estimates for the genetic coefficient of variation, heritability and genetic advance for the area under Striga number progress curve (ASUNPC), Striga emergence counts, yield and other agronomic traits, obtained in this study revealed that genetic gain for resistance to S. hermonthica could be realized through selection. Based on the performance of the 25 sorghum accessions SRN39, Danyana, Sepon82, and SAMSORG40 were the top four accessions found to be most resistant to S. hermonthica. Assessment of resistance was based on the low Striga emergence counts and the ASUNPC values. These accessions can be used as donor sources of S. hermonthica resistant genes for introgression into cultivars adapted to Nigeria, followed by recombination breeding for pyramiding the different resistance mechanisms.