Resistance of selected Soybean Genotypes and Segregating Populations to Cabbage Looper Feeding¹

Abstract

Soybean [ Glycine max L. (Merr.)] introductions PI 171451, PI 227687, and PI 229358; commercial cultivars ‘Amsoy 71’ and ‘Beeson’; and F 3 and F 4 generations of four resistant‐susceptible crosses were field tested for resistance to leaf feeding by second‐instar cabbage looper larvae ( Trichoplusia ni Hubner). The three plant introductions were highly significantly more resistant than the two commercial cultivars. The parental range in feeding scores was recovered in the F 4 generation even though the number of progenies was small. Heritabilities were estimated by correlation of F 3 with F 4 feeding scores and ranged from 6 to 44%. The possible linkage of maturity genes with genes for resistance to cabbage looper feeding in the plant introductions (maturity adapted to the Southern U.S.) did not appear to be a factor in transferring resistance to cultivars adapted in more northern latitudes.