Induction of larval ecdysis by ecdysone in the non-molting glossy (nm centre dot g) mutant larvae of Bombyx mori.

摘要

The effect of ecdysone supplemented to the artificial diet on the larval development of non-molting glossy mutant silkworm, Bombyx mori, was investigated. When the first instar larvae of nm-g mutant were isolated on day 6 after hatching and they were reared on artificial diets supplemented with various concentrations of either ecdysone or 20-hydroxyecdysone 120-OH-E), about 90% of the larvae fed on ecdysone >= 200 ppm molted to the second-instar, but only 60% of the larvae fed on 20-OH-E could molt to the second instar even though they fed on 400 ppm 20-OH-E. The second- and third-instar larvae of nm-g mutant induced by 200 ppm ecdysone molted to the next instar when they were transferred to the diet supplemented with ecdysone at the early stage of each instar. But the third- and fourth-instar larvae of nm-g mutant molted to larval-pupal intermediate or began to spinning when they were transferred to the diet supplemented With ecdysone at the late stage of each instar. These results suggest that the dietary, administration of ecdysone at an appropriate stage of each instar induces larval ecdysis effectively in the nm-g mutant larvae.