Interrelations of the Squash Bug, Anasa tristis, and Six Varieties of Squash (Cucurbita Spp.)1

Abstract

Greenhouse studies involving interactions of six varieties of Cucurbita spp. and the squash bug, Anasa tristis (De Geer) (Corei dae, Hemiptera), indicate that Butternut is the most resistant and Black Zucchini is the most susceptible of the group. A smaller amount of plant sap was removed from the more resistant plants. Lack of preference appeared to be the major factor involved in resistance. However, the resistant plants produced an antibiotic effect on nymphal development. Nymphs reared on Black Zucchini and Pink Banana attained a significantly later instar and lived longer than those reared on the other four varieties. Tolerance did not seem to be involved in the greenhouse studies. The order of resistance of the six varieties from high to low was Butternut, Royal Acorn, Sweet Cheese, Green Striped Cushaw, Pink Banana and Black Zucchini.