抄録
Prenatal maternal effects on diapause induction were examined in the tetranychid mites, Tetranychus urticae and T. kanzawai. In T. urticae, the incidence of diapause of offspring whose mothers had experienced short daylength (9L15D) was higher than that of the offspring whose mothers had experienced long daylength (16L8D) when the offspring developed under short daylength. However, this maternal effect was not conspicuous when the offspring developed under long daylength. The incidence of diapause in T. urticae offspring was higher when their mothers had experienced a high density during the juvenile period. By contrast, the photoperiod and density experienced by mothers did not affect the incidence of diapause in the offspring of T. kanzawai. However, the presence of senior female adults on the same leaf during the juvenile period enhanced the incidence of diapause in T. kanzawai. The difference in maternal effects observed between T. urticae and T. kanzawai is discussed with respect to their life-history characteristics.
