Study on the Application Effect of Unmanned Aerial Vehicle Spraying Chemical Topping Agent on Cotton

The effect of different topping methods of UAV on cotton topping was studied to provide technical support for spraying cotton topping agent by UAV. By designing three treatments of different topping methods (manual topping, UAV and locomotive) spraying topping agent, the effects of different topping treatments on the growth, yield and quality of cotton were analyzed. The results showed that the growth and development parameters of different topping treatments were not significantly different before topping. After toppling, compared with manual toppling CK (CL1), the plant height increased by 1.2cm, the leaf age and the number of fruit branches remained unchanged, the number of bolling per plant increased by 5.4, the plant height of UAV (CL2) and locomotive (CL3) with different toppling methods increased by 2.1-2.6cm, the leaf age increased by 0.9-1.1 pieces, the number of bolls per plant increased by 4-4.6, and the number of fruit branches increased by 0.3. There was no significant difference between CL2 and CL3, both of which effectively controlled the growth and development of cotton. The change trend of total dry weight was consistent with that of leaf dry weight. Manual topping (CK) had the fastest increase and the largest weight (30474.8kg/hm²), followed by locomotive topping (CL3) with 28519.6 kg/hm², and UAV topping (21469.6kg/hm²). The highest yield of seed cotton was artificial topping CK 7713.0kg/hm²; The second was CL2, which was lower than CK 1330.5kg /hm², and the difference was significant. The second is the locomotive topping CL3, lower than CK 1072.5kg/hm², the difference is significant. The quality of CL2 in the topdressing treatment of UAV is better than that of CL3 in the topdressing treatment of locomotive, and the difference between parameters is significant. CK has the best benefit of 26,000 yuan /hm², followed by the locomotive topping CL3, with the benefit of 19,000 yuan /hm² and the benefit rate of 0.7%, The third is the drone top (CL2) benefit of 18,000 yuan /hm². In summary, different topping methods can play a topping effect, the impact on the growth and development of cotton, yield and quality is different, the benefit is also different, can be selected according to actual needs.