| Dialeurodes citri (Ashmead), Homoptera, Aleyrodidae, is one of the major pests of citrus hazards. In recent years, D. citri occurred in the main citrus producing areas in Sichuan and its hazards increased year by year, even became the dominant pests in some orchards. The objective of the present study were to explore the selectivity of D. citri on three kinds citrus species in Sichuan, and the control measures on D. citri for the prevention and treatment effect. The main findings are as follows: 1 the selectivity of D. citri on three kinds citrus species in Sichuan.The difference selectivity of D. citri on Umbilical orange, Ponkan and Glorious orange in Sichuan were studied. Moreover, the effective of D. citri on the distribution of the number of the three citrus species nymphs and adults were explored, and the results showed that:the effective of Ponkan on the nymphs and adults of D. citri was the greatest (23.2 per leaf,10.5 per leaf, respectively). The effective of Umbilical orange and Glorious orange were lower. The incidence of sooty mould of the tested citrus species were compared, and the results showed that:highest incidence of sooty mould were found in Ponkan (disease index:44.61), followed with Umbilical orange and Glorious orange.In conclusion, the selectivity of D. citri on Ponkan was most obvious, seconded by Umbilical orange and Glorious orange.2 The trapping effect of different yellow sticky trap treatment on D. citri and its natural enemies.Vinegar, vitamin C, orange juice and citric acid as auxiliary agents were added onto yellow sticky trap to explore the trapping effect on D. citri and lacewing. The results indicated that the trapping effective of the different treatment on D. citri are followed as: 2.0 mL vinegar,2.0 g orange juice,2.0 g of citric acid,black control,2.0 g Vitamin C. However, the trapping effective of the different treatment on lacewing are followed as: blank control,2.0 g orange juice,2.0 g Vitamin C,2.0 g of citric acid,2.0 mL vinegar. In conclusion, adding vinegar or orange juice on yellow sticky trap has significantly enhanced the effect. Considering the trapping effect on lacewing, it is recommended to use vinegar as an adjuvant to enhance the yellow sticky trap on D. itri trapping effect.2.0 mL,3.0 mL,4.0 mL,5.0 mL,6.0 mL,8.0 mL of vinegar as an auxiliary agent were added onto yellow sticky trap to explore the trapping effect on D. citri and lacewing. The results showed that adding 2.0 mL and 6.0 mL vinegar increased the trapping effect in general and effective are followed as:2 mL vinegar,3 mL vinegar,5 mL vinegar,6 mL vinegar,4 mL vinegar. Conversely, adding 2.0 mL and 6.0 mL vinegar reduced the trapping effect. The trapping effect of different concentration of vinegar on lacewings were: blank control 1.17 per plate,5 mL vinegar and vinegar 6 mL 0.17 per plate, the rest of the treatment were 0. In conclusion,2.0 mL and 3.0 mL of vinegar as an auxiliary agent added onto the yellow sticky trap has significantly enhanced the effect, whereas reduced the effect on the lacewings population in the citrus groves.4 The control efficiency of different pesticides on D. citri.The field control efficiency of different pesticides and concentration on D. citri were investigated in the present study.6 conventional pesticides were selected, each drug set 3 concentration gradient respectively. The control efficiency were surveyed after spraying 1, 3,7 and 14 days, the results showed that:during the initial prevalence (shoots pumping stage in spring, summer and autumn), the control efficiency on the nymphs and adults of D. citri were better when using 25% thiamethoxam WDG 3000-3500 times or 48% chlorpyrifos EC 1000 times for foliar spray. Followed by a 3% acetamiprid EC 2500 times, 10% imidacloprid WP 3000 times,1.8% Avermectin EC 4000 times and 25% buprofezin WP 1500 times. |
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