The phenomenon of plant resistance to insects may be classified into three components, namely, nonpreference, antibiosis, and tolerance (Painter, 1951). Clark et al· (1972) observed that although PI 227.687 had many Heliothis zea eggs and larvae on the plants, the amount of pod damage was considerably less as compared with PI 171.451 and PI 229.358. They suggested that PI 227.687 might have some antibiosis mechanism against H.zea .
Joshi, J. M. and Wutoh, J. G.
"Research Notes: Evaluation of Commercial Soybean Cultivars for Leaf Feeding
Resistance to Heliothis zea,"
Soybean Genetics Newsletter: Vol. 3
, Article 23.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol3/iss1/23