基于苹果叶片与药液界面特性的果园农药精准喷雾量计算模型的建立

Establishment of precise pesticide spraying calculation model for orchard based on the interfacial characteristics of apple leaves and pesticide solution

为保证果树精准施药,减少药剂流失,本研究结合果树叶片冠层参数、界面性质和果园农药去向,建立了苹果园农药精准喷雾量的计算模型,以指导不同植保机械在不同果园栽种模式下的农药喷施方式。选取不同发育期‘富士’苹果叶片为研究对象,通过测定叶片表观表面自由能与冠层参数(叶面积指数、平均叶倾角),建立药液表面张力与苹果叶片最大持液量之间的关系,基于叶片最大持液量与果树冠层参数计算全树最大持液量,结合苹果园农药去向,建立了苹果园农药精准喷雾量计算模型。以担架柱塞泵式机动喷雾机在乔化稀植苹果园和风送式自走履带喷雾机在矮砧密植苹果园的施药行为为例,验证所建模型的实用性。结果表明:乔化稀植苹果园于苹果生长前期,使用担架柱塞泵式机动喷雾机,按计算用药液量施药,较常规用药液量节省药液量37.40%,生长后期则节省药液量18.75%。矮砧密植苹果园于苹果生长后期,使用风送式自走履带喷雾机,按计算用药液量施药,较常规用药液量节省药液量28%。且防效与常规药液用量无显著性差异。此模型将苹果叶片界面性质与施药器械相结合,不仅可根据果园实际情况对果园施药量进行精准计算,还可对果园某一时期农药药液的适用性进行评价,并基于实际情况调控药液量、喷雾机械参数,从而达到精准施药的目的。

In order to ensure accurate spraying of pesticides and reduce the loss of pesticides in fruit trees,a calculation model of precise pesticide spraying quantity in orchards was established.The model included the canopy parameters,interface properties of the fruit tree,and the pesticide destination in the orchard,which could be used to guide the modes of spraying for different plant protection machinery under different planting patterns in the orchard.By selecting'Fushi'apple leaves of different phenological periods as research objects,the leaf surface free energy and canopy parameters were tested.The relationship between liquid surface tension and maximum liquid holdup was established for apple leaves.The maximum pesticide loading of the whole tree was calculated based on maximum liquid holdup and canopy parameters.The calculation model of precise pesticide spraying quantity was established,combined with the pesticide destination in the orchard.The application of two kinds of spraying machines,stretcher plunger pump sprayer in the low-density planting orchard and selfpropelled axial flow sprayer in the close planting orchard,were taken as examples,and the practicability of the model was verified.The results showed that the use of a stretcher plunger pump sprayer in the early stage in the low-density planting orchard could save 37.40%of liquid compared with the original,and 18.75%of liquid could be saved in the later stage.The use of a self-propelled axial flow sprayer in the late stage of the close planting orchard can save 28%of the liquid.There was no significant difference between the control efficacy and the dosage of conventional liquid medicine.This model combined the interface properties of apple leaves with the application equipment could not only calculate accurately the spraying amount of pesticide according to the actual situation of the orchard,but also evaluate the applicability of pesticide liquid at a certain period.The mode could adjust the parameters of the pesticide liquid and spray machine according to the actual situation,so as to achieve the purpose of precise pesticide application.