In the leek moth Acrolepiopsis assectella (Hyponomeutoidea), a specialist phytophagous insect which attacks the leek, Allium porrum (Liliacae), the choice of larval host plant is made by the female. The female is attracted by thiosulphinates emitted by the plant (Lecomte & Thibout, 1981), but egg-laying takes place only after prolonged contact with the leaves. This might suggest that non-volatile
... [Show full abstract] cues are involved in triggering oviposition as is the case in other Lepidoptera (Ren-wick & Chew, 1994). Detailed observations of the egg-laying behaviour were made and preliminary experiments were carried out in an attempt to identify the substances responsible for stimulation of oviposition.