Challenges and opportunities of unmanned aerial vehicles as a new tool for crop pest control

The application of pesticides is not simply delivering chemicals to the target area. It also involves considering the negative aspects and developing strategies to deal with them during the application process, to ensure the maximization of pesticides use efficiency and the maintenance of the ecosystem. Unmanned aerial vehicle (UAV) sprayers demonstrate unique advantages compared to traditional ground sprayers, particularly in terms of maneuverability and labor intensity reduction, showed great potential for chemical application in pest control. It is undeniable that there exist challenges in the practice of UAV spraying, such as higher potential risks of pesticide drift or pathogen transmission, uncertainty canopy deposition for different crops, and unexpected leaf breakage induced by downwash flow. Maximizing the utilization of downwash flow while avoiding lateral air movement outside the intended target crop area is a major issue for chemical application with UAV sprayers, particularly in light of the increasingly apparent consensus on the need for enhanced environmental protection during the chemical application process. It must be considered that the operation strategy in different scenarios and for different crop targets is not the same, unique requirements should be given on nozzle atomization, flight parameters, adjuvants and aircraft types in specific working situations. In future, the implementation of spray drift prediction, technical procedures development, and other solutions aimed at reducing pesticide drift and improving deposition quality, is expected to promote the adoption of UAV sprayers by more farmers. © 2023 Society of Chemical Industry.     

Sublethal effects of nine insecticides on Drosophila suzukii and its major pupal parasitoid Trichopria drosophilae

Background

Although the pupal parasitoid Trichopria drosophilae is used in conservative and augmentative biocontrol of Drosophila suzukii infestations, current pest management strategies mostly rely on multiple insecticide applications. In this context, the aim of the study was to investigate the baseline toxicity of nine insecticides on D. suzukii larvae and their multiple sublethal effects (LC₁₀) on immature stages of the pest feeding on contaminated diet and T. drosophilae developing within the intoxicated host.

Results

Chlorpyriphos and azadirachtin showed the lowest and the highest LC₁₀, the values of which were 9.78 × 10¹³ and 1.46 × 10³ times lower than their recommended label field rate, respectively. Among tested insecticides, imidacloprid, malathion and dimethoate were the only treatments that did not affect the juvenile development time of D. suzukii, while spinosad and the organophosphates chlorpyriphos and dimethoate did not influence fly pupal size. No sublethal effects were recorded on T. drosophilae degree of infestation (DI) and juvenile development time. On the contrary, cyazypyr and dimethoate negatively affected the success of parasitism (SP) and the number of progeny of the pupal parasitoid, in association with malathion for the first parameter and spinosad for the fertility. Compared to the untreated control, more female progeny emerged following azadirachtin exposure, while dimethoate caused the opposite effect. Imidacloprid, lambda-cyhalothrin and spinetoram decreased hind tibia length of emerged parasitoids.

Conclusion

This study provides new insights on the (eco)toxicological profile of nine insecticides and new information needed to support the deployment of T. drosophilae in the field within the sustainable management techniques against D. suzukii. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

甘肃陇西黄芩灰霉病病原菌分离鉴定及田间药剂防治

为探明黄芩(Scutellaria baicalensis Georgi)茎基部和根部灰霉病的病原菌,本文于2019—2021年春季对甘肃陇西县采集的黄芩病样进行病原菌的分离培养,运用形态学和内转录间隔区(Internal transcribed spacer, ITS)、甘油醛-3-磷酸脱氢酶(Glyceraldehyde-3-phosphate dehydrogenase,G3PDH)、热激蛋白60(Heat shock protein 60,HSP60)和RNA聚合酶亚基II(The second largest subunit of the nuclear RNA polymerase enzyme II,RPB2)多基因方法鉴定,采用菌丝生长抑制法进行药剂室内毒力测定和田间药剂防治试验。结果表明：引起黄芩灰霉病的病原菌为灰葡萄孢(Botrytis cinerea),春季发病时表现为地上部分枯死不发芽,靠近地表的根表面呈暗绿色水渍状,随后地下根木质部变软呈黄褐色腐烂,病健交界明显;室内毒力测定表明,97%咯菌腈对灰葡萄孢菌的抑菌作用最强,EC₅₀为0.01...     

卡巴匹林钙水分测定法的改进

对《中国兽药典》中卡巴匹林钙的水分测定法进行了改进,从取样量、加入样品后的搅拌时间、二甲基甲酰胺与无水甲醇的比例、连续测定样品的份数、滴定杯中的溶剂使用量5个方面对现行标准方法进行了优化,解决了现行标准方法测定结果平行性差、无法真实反映产品质量等问题。通过与干燥失重法和气相色谱法的比较,验证了改进后方法的可靠性。还对现行标准方法问题产生的原因、实验的注意事项等进行了研究。     

双向电液比例张力绞车的直接自适应鲁棒控制

设计了基于比例溢流阀调压回路的双向电液比例张力绞车,并进行了理论分析。针对液压系统的不确定性因素以及卷绕机构参数变化对张力控制的影响,提出了直接自适应鲁棒电液张力控制方法,并用张力负载模拟试验系统进行了研究。理论分析与试验均表明,对于具有不确定性因素的张力跟踪控制,所设计的电液张力绞车及其控制策略,具有良好的控制性能。     

梳脱式联合收割机脱粒与输送装置模糊控制系统

建立了梳脱式联合收割机脱粒与输送装置的动力学模型，应用Fuzzytoo1box设计了模糊控制器。当作物属性变化等因素而引起该装置的工作负荷发生较大变化时，模糊控制器能够对机组前进速度傲出相应的调整，使被控量迅速恢复到设定值附近，且能保持稳定，有利于发挥机器的最大的工作潜能，提高机器的可靠性，降低机器故障率。