Evaluation of Selected Soybean Genotypes for Resistance to Two Whitefly Species (Homoptera: Aleyrodidae) in the Greenhouse
Fourteen soybean cultivars and breeding lines in Maturity Groups VII and VIII were monitored for silverleaf whitefly, Bemisia argentifolii Bellows and Perring, and greenhouse whitefly, Trialeurodes vaporariorum (Westwood), infestation levels in the greenhouse. Unifoliate leaves became infested with whitefly immatures and eggs 4 wks after planting. LA88-32 and F90-700 had significantly higher total whitefly populations than 11 and eight of the other entries, respectively, at growth stage V7. Whitefly populations were higher 6 wks after planting (growth stage V8–V9) when a unifoliate leaf and trifoliate leaves 1, 2, and 3 were sampled. G89-5180, Perrin, F90-988, G89-5066, N89-1, and N88-91 had significantly lower total numbers of whiteflies than F90-724, F90-700, and LA88-32. At 10 wks after planting (growth stage R2), G89-5180 and N88-91 had the lowest numbers of whiteflies, and total counts were significantly higher for F90-724 on trifoliolates 2, 4, and 6. Leaf damage ratings (% leaf burn) ranged from 1.3% (F90-724) to 74.0% (F90-1054). Sampling ceased after 10 wks because of excessive whitefly-induced plant injury to most soybean entries. This study reflected significant differences in soybean varietal response to whitefly population densities and demonstrated that the greenhouse can be used effectively to screen soybeans for resistance to whiteflies.