Control Effect on Cotton Aphids of Nanopesticide Sprayed with Plant Protection Unmanned Aerial Vehicles in Cotton Field

PurposeTo explore droplet deposition and control effect of nanopesticide on cotton aphids, spray tests were carried out by plant protection unmanned aerial vehicle (UAV) in cotton field (seedling stage).

MethodsNanopesticide (3.5% acetamiprid) and conventional pesticide (5% acetamiprid and 2.5% lambda-cyhalothrin) were sprayed by Anyang Quanfeng 3WQF120-12 UAV under two flight heights (1.5 and 2.5 m). Allura red was used as a tracer in determination of droplet deposition and pesticide utilization. The droplet density and coverage rate were analyzed by image processing software Image J.

ResultsThere was no significant difference in droplet deposition density and coverage rate on cotton when conventional pesticide or nanopesticide sprayed by UAV at flight height of 1.5 m and 2.5 m (P>0.05). The droplet density (73.84-95.12 cm⁻²) and coverage rate (1.92%-3.22%) of nanopesticide were lower than those of conventional pesticide (108.57-116.59 cm⁻² and 3.86%-4.08%). The utilization rate (2.39%-2.75%) of nanopesticide spraying was lower than that of conventional pesticide (3.89%-4.09%). Nanopesticide droplets had smaller particle size, and seven days after application, the efficacies of nanopesticide sprayed by UAV (89.79%-95.23%) were significantly higher than those of conventional pesticide (70.52%-79.01%) (P<0.05). The control effect of cotton aphid reached the level of manual spray at the height of 1.5 m.

ConclusionIn the seedling stage of cotton, 3.5% acetamiamidine·beta-cyhalothrin nanometer pesticide sprayed by UAV at a height of 1.5 m can effectively control cotton aphid, which can be widely applied in the field.