Oviposition of potato tuber moth, Phthorimaea operculella Zell. (Lepidoptera: Gelechildae); the physical nature of the oviposition substrate

Abstract

Laboratory experiments were conducted to define physically optimum oviposition substrates for potato tuber moth. Surface depressions just large enough to accommodate eggs (0.2–0.5 mm³) were preferred, but in addition hairy substrates were much more attractive than smooth. Mechanical stimulation of tactile hairs on the ovipositor may account for these effects. Similar numbers of eggs were laid over a 48 h period by most females regardless of substrates provided, and substrate preference was indicated by the distribution of eggs. Exceptions occurred with highly deterrent surfaces, especially those that were moist, when the total number of eggs laid was reduced.