Comparison of the effectiveness of applying different pesticides to foliar spraying and soil-drench to control Diaphorina citri Kuwayama
Author of the article:CHENG Xiao-Qin; ZHAO Zheng;XIA Chang-Xiu;YAN Xiang;ZHANG Ri-Hua; ZHANG Hong-Yu
Author's Workplace:Institute of Urban and Horticultural Pests, China-Australia Joint Centre Research for Horticultural and Urban Pests, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Ganzhou Institute of Citrus Science, Ganzhou 341000, China; Department of Plant Protection Development, Syngenta (China) Investment Co., LTD, Haikou 570125, China
Key Words: Diaphorina citri Kuwayama, toxicity test, foliar spraying, soil-drench, chemical control
Abstract:
[Objectives] To
identify pesticides that are
effective against Diaphorina citri Kuwayama but that have low environmental toxicity, and provide a theoretical
basis for the comprehensive prevention and control of citrus Huanglongbing
(HLB). [Methods] The toxicity and
effectiveness of 12 pesticides was evaluated using the indoor membrane method
and field bioassays. The effectiveness of low-toxicity pesticides suitable for
spraying on foliage and applying to soil was assessed and optimal
concentrations determined. [Results] Of the 12 pesticides tested for indoor
virulence, 48% Clothianidin, 45% Chlorpyrifos, 10% Cyantraniliprole and 20%
Dinotefuran were the most virulent to adult D.
citri with LC50 of 1.42, 1.48, 1.49, 1.60 mg/L, respectively.
The results of field leaf spraying tests showed that applying 20% Dinotefuran
and 10% Cyantraniliprole was c. 90% effective after 7 days with a comprehensive
effect better than that of the other 10 pesticides. The results of soil-drench
tests indicated a cumulative reduction rate of 30%. Thiamethoxam was 100%
effective after 7 days, significantly higher than the other four
pesticides tested. The efficacy of applying 30% Thiamethoxam to soil at
concentrations of 100 mg/L and 150 mg/L reached 60% after 30 days, and 100%
after 7 days. [Conclusion] 20%
Dinotefuran at 150 mg/mLor 10% Cyantranil at 100 mg/mL were the most effective
pesticides and dosages sprayed on foliage, whereas 30% Thiamethoxam at 100
mg/mL was the most effective pesticide applied to soil.