Abstract
Adult females of the stink bug, Piezodorus hybneri, were collected in a soybean field to investigate the state of ovarian development and some characteristics of oviposition. In 1989, more than 80% of females had mature eggs. Newly-emerged adults with immature ovaries were found from the end of July. In 1991, a total of 54 female immigrant bugs were collected immediately after they invaded a soybean field. Thirty were dissected to examine their ovarian maturation; the remaining 24 were reared individually under laboratory conditions of 25°C and 14L-10D. Most dissected female bugs had mature eggs and were already mated. The mean survival of the immigrant females was 40.2±22.8 (±SD) days after collection. All reared females laid fertilized eggs within 5 days after collection. The mean number of egg-masses laid per female was 9.5. The mean number of eggs per egg-mass was 25.0 and the hatchability of eggs was 83.7%.
