Impact factors determining offspring sex ratio of Fopius vandenboschi

Fopius vandenboschi(Fullaway) operated as a parasite of Bactrocera dorsalis(Hendel) larval at various ages,the female sex ratio of F.vandenboschi emerging from parasitized 4-day-old hosts was 58.27%,and that from 1-day-old hosts was 15.29%.The female sex ratio of progeny increased as the age of the host increased.The female sex ratio decreased with increasing wasp density,B.dorsalis larvae were exposed to 20 parasitoids produced progeny with the smallest female sex ratio 24.32%.Whereas the greatest female sex ratio 53.65% was obtained for those exposed to 1 parasitoid.The female sex ratio of progeny was 31.97% when hosts parasitoid by females aged 5 days,parasitoid by females aged 10 days was 44.39%.The female sex ratio rose as the age of the female wasps increased.But the sex ratio varied in significantly among progeny produced by females aged 10 to 30 days.A high temperature(35 ℃) affected the female sex ratio of the progeny of F.vandenboschi,but there was no effect at 15 ℃.No distinction was found in the female sex ratio of the progeny from female parasitoids depending on varied foods.