Effects of different sprayers on the deposition quantity of fenhexamid on the tomato leaves and the efficacy against Botrytis cinerea

Pesticides deposit amount is one of the important criteria to determine the effective utilization rate of pesticide. Three kinds of sprayers were used to spray 10% fenhexamid wettable powder, an effective fungicide agency for the control of the Botrytis cinerea, onto the leaves of the tomato cultivated in greenhouse. Some of the leaves were collected 2 h after the spay to evaluate the deposition quantity through gas chromatography and UECD detector. The results showed that the deposition amount of fenhexamid on the tomato leaves, which were sprayed by 3WBD-16 dynamoelectric knapsack sprayer and 3WJD-18 electrostatic sprayer reached about 3.25 mg/kg and 5.61 mg/kg respectively, while the leaves sprayed by the TSP-60 (S) thermal fogger had the highest deposition amount of 12.83 mg/kg. The efficacies of TSP-60 (S) thermal fogger against B. cinerea occurring in leaves and fruits were also with the highest rate of 86.53% on tomato's leaves and 85.50% on fruits,which were significant higher than those conducted by the dynamoelectric knapsack sprayer (73.88% on tomato's leaves and 74.03% on fruits). The efficacy of electrostatic sprayer on tomato's leaves (77.45%) was clearly lower than that of TSP-60 (S) thermal fogger, and which on fruits (79.85%) was not significant with that in TSP-60 (S) thermal fogger. In general, TSP-60 (S) thermal fogger and 3WJD-18 electrostatic sprayer can greatly improve the deposition quantity of fenhexamid on tomato leaves and promote the control efficacies against B. cinerea for the tomato in greenhouse.