Abstract
Twenty species and two subspecies comprising 370 accessions of the USDA Digitaria collection were screened in laboratory trials for resistance to the yellow sugar-cane aphid, Sipha flava (Forbes). Differential aphid resistance existed among species and accessions. Four accessions within the species, D. diversinervis, D. longiflora and D. friesii and one accession unidentified as to species exhibited a high degree of aphid resistance. Additional accessions contained lower levels of resistance. Paramount consideration should be given to the behaviour of accessions in the continued search for aphid resistant germplasm. The results indicate that antibiosis and possibly non-preference is present in certain accessions; such results suggest further study of the mechanism of resistance.
