Technique Optimization Of Mass Rearing Oriental Fruit Fly, Bactrocera Dorsalis (Hendel)

In order to optimize the technique of mass rearing oriental fruit fly, Bactrocera dorsalis (Hendel),the principal ingredients of larval artificial diet, adult population density of rearing cage, adult sex ratio, cryopreservation of the pupa were studied in this paper based on the previous studies.According to orthogonal experimental design, with larvae artificial diet of different components of wheat bran, sugar, beer yeast, artificial preservatives oriental fruit fly were reared. Pupateion rate, pupal weight, adult emergence rate, egg production of each female and egg hatch percent were studied to optimize the diets. Wheat bran had marked influence on pupal weight.Sucrose significantly influenced pupal weight, pupate rate, adult emergence rate and egg hatch percent; Spent brewer's yeast had marked influence on pupal weight, pupation rate and egg hatch percent. Artificial preservatives had great influence on pupation rate and pupae weigh, but had no effect on adult emergence rate, egg production of each female and egg hatch percent. The optimal formula of larvae artificial diets was 104g of wheat bran, 69.6g of sugar, 25.2 g of spent brewer's yeast and 1.1g of artificial preservatives(Methyl p-hydroxybenzoate : Sodium benzoate=1:1) per 200g. Pupation rate 99.33±0.33%, pupal weight 13.02±0.16mg, adult emergence rate 94.67±0.33%, egg production of each female 275.43±25.17 and egg hatch percent 72.78±2.74% were got used the above formula.Pupation rate, pupal weight, adult emergence rate and egg hatch percent were studied to optimize adult population density in rearing cages. The optimal density was that each adult to share of 2.47cm2 of surface area.Based on the studies of egg hatch percent the largest sex ratio of adult males and females in each rearing cage could bear was 3:1.The pupal period, adult emergence rate and adult sex ratio of different age pupa placed under different temperatures and held different time were studied. Temperature, pupal age, storage time and interaction between them had significant influence on emergence rate. The 8-day-old pupae preserved at 13℃in eight days got 90±2.89% emergence rate, and the pupal period was 19.75 days. The emergence rate was 81.67±6.01% of the 6-day-old pupae preserved at 16℃about twelve days , and the pupal period was 21.25 days. Emergence rate of female was higher than that of male under lower temperature, and the sex ratio would increase with the extension of storage time. Female's cold-resistant ability was stronger than the male's.