Effects of juvenile hormone and ecdysteroid on ovarian development of the Japanese oak silkworm Antheraea yamamai.

When the larvae of Antheraea at the middle stage of the 5th instar were treated with Juvenile hormone analogue (methoprene) and exogenous ecdysteroid (β-ecdysone) , respectively, their ovarian development were not significantly different from those of the control. Through treating pupae at the 1st day after pupation with methoprene and 20-hydroecdysone, the results revealed that ecdysteroid could stimulate ovarian development at pupal stage and conversely for juvenile hormone. It seems that methoprene could enhance total egg number of the female moth which the 5th instar larvae were treated with methoprene. As for ecdysteroid, it .seems to show a contrary effect. In addition, the possibility for the application of these two hormones in egg raising of this silkwonn was discussed.