Squash Bug Ovipositional Preference within Cucurbita pepo

Abstract

The Squash bug (SB), Anasa tristis, is a devastating insect specialist of squash (Cucurbita pepo) that lays egg clusters on leaves. SB feeding can cause 50% yield losses in conventional and organic systems. SB preference studies in C. pepo have been performed, although with limited cultivars and unreliable results. Cocozelle, pumpkin, vegetable marrow, and zucchini are included in C. pepo subsp. pepo, while C. pepo subsp. texana includes acorn, crookneck, scallop, and straightneck squash. A previous study in the lab revealed a significant SB ovipositional preference for squash in the C. pepo subsp. texana including a preference for cultivars within the scallop and acorn market classes. The objectives of this study were to identify SB ovipositional preference within three C. pepo market class panels at the cultivar level. The within zucchini, acorn, and scallop market class assays were performed in replicated small greenhouse cages with one plant per cultivar and 5 mating pairs released into the cages. Oviposition data was taken at three days and analyzed with a mix model ANOVA using JMP13. While no SB preference within the eight cultivar scallop panel was detected, the eight cultivar acorn panel revealed significant preference for oviposition of several cultivars with Thelma Sanders (P=0.05) being the most preferred. The six cultivar panel of zucchini revealed a significant preference (P=0.05) for several zucchini cultivars with three cultivars (Golden Zucchini, Parthenon, and Caserta) being highly non-preferred. These results may be informative for growers in areas with high levels of SB pressure.