Abstract
Factors involved in the oviposition response of the limabean pod borer, Etiella Zinckenella TREITSHKE were examined, using soybean plants as the substrate under a net cage (30×30×40 cm) condition. Gravid females preferred to oviposit among hairs on the plant surface for a pubescent variety, while they oviposited preferentially under the sepals and stipels for a glabrous one. When the pod was taped with a wax paper band, most eggs were laid crowded together under it, particularly in the pod banded at the proximal part. In a pod taped with double papers, the number of eggs laid between the two papers was almost the same as those between the lower paper and the pod surface. Ovipositional preferences to the fresh, dried, and water-sucking (dried) pod were compared in both free-choice and no-choice situations. In both tests, the eggs deposited on the dried pod were much fewer than those on the other two pods. A few more eggs were found on the fresh pod than on the water-sucking one. These results suggest that the physical texture and moisture of the substrate act strongly on the oviposition response of E. zinckenella, and odor influences only weakly. Contact chemostimuli seem not to be contributive, at least, in the final step of oviposition behavior.
