Effects of Plant Flavonoids on Fecundity, Survival, and Feeding of the Formosan Subterranean Termite.

Fecundity, mortality, and food consumption of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were evaluated in response to five plant ifavonoids (genistein, biochanin A, apigenin, quercetin, and glyceohm). Apigenin fed at 50 μg/primary reproductive pair proved to be the most toxic fiavonoid. Biochanin A was most effective in reducing fecundity. Subsequently, these two flavonoids were tested through oral feeding and topical application at 100-μg dose. Significant reduction in the numbers of progeny was evident for biochanin A in both treatment methods. Choice feeding tests with termite workers showed that initially termites were attracted to filter paper treated with biochanin A, but over a period of 72 hr, consumed significantly less material when compared to controls. Biochanin A is a promising phytochemical with ability to reduce fecundity in primary reproductives of the Formosan subterranean termite, but it does not elicit phagostimulant activity. [ABSTRACT FROM AUTHOR]