The effect of egg load on readiness to accept a low-quality host plant is weak and age dependent in a geometrid moth

Abstract.  1. Most empirical and theoretical studies treat egg load as a major determinant of insect oviposition behaviour, and predict a positive link between egg load and readiness to oviposit.
2. In the present study, the correlation between egg load and readiness to lay eggs on a low-ranked host was examined in wild-caught moths, Scotopteryx chenopodiata L. (Lepidoptera: Geometridae).
3. No overall effect of egg load on oviposition could be detected. However, there was a significant interaction between egg load and wing wear: in only one wing-wear class, out of four, high egg load tended to promote oviposition, while in the three other classes the effect was insignificant.
4. The results suggest that the effect of egg load on oviposition may depend on the age of the ovipositing insect.