【摘要】 雾滴直径、密度和沉积率直接影响着农药在茶园空间的分布。采用机动弥雾、手动吹雾和小喷孔片等低容量喷雾与常规喷雾(常量法)进行比较试验,结果表明,前者对分布在茶树冠面0—10cm的芽叶害虫的农药中靶率高达60%—79%,较后者高10%—17%,但在茶树中下部的农药沉积率则反之(小喷孔片除外),农药在土壤中的流失量,常量法明显高于低容量喷雾。不同喷雾技术农药在茶树上的化学降解速率和半衰期相近,主要差异在于原始附着量的高低,其高低次序为机动弥雾>手动吹雾>小喷孔片>常量喷雾。农药的安全间隔期和对芽叶害虫的防治效果,低容量喷雾的半剂量处理与常量喷雾的全剂量处理相近。单位面积的农药沉积量及雾滴数与害虫的死亡率呈明显的正相关。各种喷雾技术在树冠面的农药沉积量均已超过害虫的致死量,故在芽叶害虫的防效上无明显差异。重点在于通过改进喷雾技术,以提高低容量喷雾对丛内病虫的防效。在研究的基础上,提出了适用于不同类型、地形、集约化程度及不同分布部位病虫的茶园农药优化使用技术方案,按此方案喷药,可获得显著的经济效益及社会效益。更多还原

【Abstract】 The space distribution of pesticide in tea garden is influenced by thediameter and density of the droplet as well as by the percentage of pesti-cide deposit.The droplet from the low-volume spraying is relatively small,and the percentage of hits to the target-pests situated on the 0—10cmsurface of tea canopy can be as high as 60—70%,10—17% higher than thatfrom the normal-volume spraying which produces larger droplet.However,the percentage of the hits from the normal-volume spraying on the middleand lower parts of tea canopy as well as on the soil surface is higher thanthat from the low-volume spraying.The chemical degradative rate and thehalf-life of the pesticide sprayed on the tea plant with various sprayingtechniques are similar.However,the initial deposit is different,i.e.thedeposit from the low-volume spraying is higher than that from the normal-volume spraying under the condition of half-dosage application.The safetyinterval in the low-volume spraying treatment is similar to that in thetreatment of full-dosage with normal-volume spraying.Results of experi-ment showed that the mortality of target-pest is closely related to thenumber of droplet and the deposit amounts of pesticide per unit leaf area.The difference on the efficacy to the pests on the canopy of tea plant isinsignificant among the different spraying techniques.But it is quiteobvious different on the efficacy to those pests situated in the inner partof tea canoly.However,this low efficacy can be increased through impro-ving the spraying technique.An optimizing technical scheme on the pesticideapplication in tea garden was put forward.A significant economic efficiencyhas been obtained from the demonstration experiment in a large scale.更多还原