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ULV Application to a Tree Crop Canopy: Evaluation of Physical Performance and Penetration

  • Kwame Afreh-Nuamah
  • E. W. Thornhill
Article

Abstract

Spray distribution in an apple tree canopy using an adapted knapsack mistblower fitted with a spinning disc, with the provision of an induced electrostatic charge on the droplets was studied.

Droplets were sampled using uvitex fluorescent tracer on Kromekote cards positioned in different areas of the canopy.

Droplets were highest on the outer surface and decreased sharply into the canopy. Uncharged spray droplets gave the poorer deposition with better distribution, but by adding an electrostatic charge, droplet deposition was significantly improved in the outer parts of the canopy. An average of 3 ml/tree of spray liquid was used in all applications. The larger variety (Red Victoria) required about 50% more spray liquid, but distribution was still lower than that achieved by the smaller Keswick variety.

Keywords

Ultra low volume (ULV) spinning disc droplets tree crop canopy distribution 

Résumé

Une étude a été faite sur la distribution dans la pulvérisation de la cime d’un pommier en utilisant un pulvérisateur à dos adapté, avec un gicleur ayant un aménagement pour l’induction de charges électro-statiques des gouttelettes.

Les gouttelettes ont été analysées à l’aide d’un tracer fluorescent Uvitex sur des cartes kromekote positionées dans des places différentes de la cime du pommier.

La déposition qui était plus supérieure dans la surface extérieure décroissait brusquement dans la surface intérieure de la cime. Les gouttelettes non-chargées malgré leur faibre déposition avaient la meilleure distribution. Cependant, par le rajout des charges électro-statique, la déposition des gouttelettes était amméliorée d’une manière remarquable dans les parties extérieures de la cime du pommier. En moyenne, 3 ml/arbre de solution étaient utilisés dans toute les application. Les arbres connaissaient une baisse progressive de pulvérisation, et en conséquence, une faibre déposition, sur charque unité de surface des feuilles au fur et à mesure que l’étendue de la cime ou la taille de l’arbre accroissaient, cette déposition, par contre, étaint presque nulle dans les parties selon qu’ils soient loin ou qu’ils soient protégés du pulvériseur.

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Copyright information

© ICIPE 1988

Authors and Affiliations

  • Kwame Afreh-Nuamah
    • 1
  • E. W. Thornhill
    • 1
  1. 1.International Pesticide Application Research CentreImperial College at Silwood ParkAscotEngland

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