Abstract:
To avoid the hazards of pesticide residues, high-voltage electrostatic discharge was recommended to kill tobacco aphid. The pest control effects via the traditional pesticides and high-voltage electrostatic discharge were compared. The test apparatus of high voltage electrostatic disinsection is adjustable from 20 to 60 kV high voltage. The initial test voltage is 40 kV, and the probe scanning distance is 25 mm. The probe terminals were to scan the tobacco leaves from its bottom to top, close to the tobacco leaves surface. Since disturbance of the probe, the front and back of the tobacco leaves were all in the electric field. The scan time is about 1-2 s. For the traditional pesticide pest control, the pesticide “KANGFUDUO” with a concentration of 20% diluting for 4000 times was used. The conventional spraying method was employed, 750 liters per hectare of water consumption. The test plot is 330 m2 and divided into three blocks with an isolation belt of 2 meters in width for each two blocks. Each block of field was with 200 plants with a plant spacing of 0.55 meter and the line spacing of 1.1 meter. One block was subjected to electrostatic pest control, one was to undergo pesticide pest control, and the remaining block was arranged for reference. Listed sampling method was used for the electrostatic pest control, pesticide pest control, as well as the reference block and the number of the aphid was nearly the same. 3 replicates were conducted and data were averaged. The height of the test tobacco plant is 1.2 to 1.5 meters, 12 to 14 leaves. The trial was conducted during 10 consecutive sunny days. The types and quantities of field pests before pest control test were investigated and recorded. The pest control effects were analyzed after treatment for 1 day, 5 days and 9 days, respectively. The study shows that the rate of pest control by using high voltage electrostatic discharge method was up to 70.38%-78.73%, lower than the pesticide pest control(92.97%-95.96%), yet it is non-toxic, and has little effect on the natural enemies of the ladybug. On the basis of the experimental data, a high-voltage electrostatic crop pest control parameters were optimized, which provides a technical basis for the design and manufacture of high-voltage electrostatic crop pest control machine. To 1 day of pest control effect treated as a target, L9 (33) orthogonal tables were arranged, 3 factors are test voltage (A), scan time (B) and scanning distance (C). Through orthogonal optimization, the optimal pest control voltage (50 kV), pest control time (3 s) and pest control distance (15 mm) were determined. The aphid-killing rate with the optimal parameters is up to 83%.