Comparison of sexual dimorphism between G1 and G2 in Brithys crini Fabricius(Lepidoptera: Noctuidae)

To understand the sexual dimorphism of Brithys crini Fabricius and effects of different generations on the sexual dimorphism,the body weight and size of generation 1(G1) and generation 2(G2) were compared under the laboratory conditions.The results showed:(1)There was sexual dimorphism in G1 and G2 of B.crini reared in the laboratory.The female was larger than the male.(2)Sexual dimorphism differed between G1 and G2.Sexual dimorphism in G1 was more obvious than that in G2.These results indicated that the sexual dimorphism in B.crini maybe different from different generations reared in the laboratory.