Abstract
Incidence of egg parasitoids of Riptortus clavatus before and during soybean cultivation was investigated by placing host eggs on soybean and other leguminous plants in Tsukuba between May and October, 1985, and between April and May, 1986. Gryon japonicum, G. sp., Ooencyrtus nezarae, O. sp., and Anastatus japonicus were identified as the egg parasitoids. G. japonicum was found on soybeans from middle July to early October, mainly when pods were growing. This parasitoid was also common on white clover, common vetch and alfalfa as early as May, before soybean cultivation.
