Deposition of spray applied in coffee leaves with different rates and spray nozzles/Deposicao de calda em folhas de cafeeiro e perdas para o solo com diferentes taxas de aplicacao e pontas de pulverizacao

• Published in: Revista brasileira de engenharia agrícola e ambiental 2014-12, Vol.18 (12), p.1302
• Main Authors: Silva, Joao E.R, da Cunha, Joao P.A.R, Nomelini, Quintiliano S.S
• Format: Article
• Language: Spanish
• Subjects: Analysis; Pesticides; Tracers (Biology)
• ISSN: 1415-4366
• DOI: 10.1590/1807-1929/agriambi.v18n12p1302-1306

The coffee crop (Coffea arabica L.) has many challenges for the pesticide application technology, mainly with respect to the spray penetration in the orchard and drift reduction. The aim of this study was to evaluate the spray deposition on leaves of coffee plants and the loss to the soil provided by the application with different spray volumes and nozzles. The study was conducted using a factorial model 2 x 2, with two nozzles (hollow cone--ATR and hollow cone with air induction--TVI) and two rates (200 and 500 L [ha.sup.-1]). The brilliant blue tracer was added to the tank, which was detected by spectrophotometry after the application using an airblast sprayer. Leaves were collected from the upper and lower parts of the plant canopy and glass slides were positioned on the ground under the plant canopy, to collect the drained drops. The use of hollow cone nozzles with air induction together with the use of higher spraying rate (500 L [ha.sup.-1]) was feasible on the spray deposition in the coffee leaves. The lower spray rate (200 L [ha.sup.-1]) was feasible together with hollow cone nozzle. The hollow cone with air induction nozzle resulted in higher losses to the soil. Palavras-chave: bico de pulverizacao Coffea arabica turbo-atomizador volume de aplicacao O cafeeiro apresenta diversos desafios para a tecnologia de aplicacao dos produtos fitossanitarios, principalmente no que se refere a penetracao da calda no dossel da cultura e a reducao da deriva. Objetivou-se analisar a deposicao de calda pulverizada na folhagem do cafeeiro e a perda para o solo, proporcionada pela aplicacao com diferentes taxas e pontas de pulverizacao. O experimento foi conduzido no esquema fatorial 2 x 2 e oito repeticoes, sendo os fatores pontas de pulverizacao (jato conico vazio--ATR e jato conico vazio com inducao de ar--TVI) e taxas de aplicacao de calda (200 e 500 L [ha.sup.-1]). Em todos os tratamentos as aplicacoes foram realizadas utilizando-se um pulverizador hidropneumatico e o marcador Azul Brilhante, o qual foi quantificado por espectrofotometria. Para avaliacao de deposito foram coletadas folhas das metades superior e inferior das plantas e tambem laminas de vidro ja posicionadas junto a superficie do solo. O uso de pontas com inducao de ar mostrou-se viavel quanto a deposicao de calda no cafeeiro, principalmente junto ao uso da maior taxa de aplicacao. O emprego da menor taxa (200 L [ha.sup.-1]) mostrou-se viavel junto ao uso da ponta de jato conico vazio. A ponta co