Análise da pulverização de um fungicida na cultura do feijão, em função do tipo de ponta e do volume aplicado

Abstract

LUIZ CLAUDIO GARCIA (2) ; ALTAIR JUSTINO (3) ; HAMILTON HUMBERTO RAMOS (4) RESUMO A cultura do feijão (Phaseolus vulgaris L.) é uma das mais importantes na agricultura brasileira. A ocorrência de doenças é um sério fator de influência no seu desenvolvimento e produtividade. Objetivou-se com o experimento instalado no município de Ponta Grossa (PR) analisar diferentes condições de pulverização para aplicação de um fungicida. Semeou-se a cultivar carioca FTBonito em janeiro de 2001. Realizou-se a pulverização do ingrediente ativo azoxystrobin com pulverizador costal pressurizado com CO 2 . Os tratamentos foram compostos por dois tipos de pontas (jato plano e cônico vazio) e por dois métodos de determinação do volume de calda aplicado, fornecido pelo fabricante e pelo índice de área foliar -IAF. O volume definido pelo IAF foi acurado pela proporcionalidade com o máximo valor do referido índice, obtido previamente por meio de ensaio em estufa. Avaliaram-se a incidência e severidade das doenças e a produtividade. O delineamento experimental adotado foi o de blocos casualizados e as médias obtidas, comparadas pelo teste de Tukey e os grupos de médias, pelo teste de Scheffé. Os dados obtidos demonstraram que foi necessário o tratamento fúngico para a região dos Campos Gerais, na safra das secas, principalmente para o controle de mancha-angular (Phaeoisariopsis griseola). Verificou-se que o tipo de ponta utilizado foi indiferente em relação ao controle quando se aplicou azoxystrobin. O volume de calda pulverizado pode ser calculado com base no IAF da cultura, com economia até de 69% do custo de aplicação, nas condições do ensaio. Palavras-chave: área foliar, severidade, produtividade. ABSTRACT ANALYSIS OF NOZZLE TYPE AND SPRAYING VOLUME OF A FUNGICIDE APPLIED ON THE BEAN CROPSBean (Phaseolus vulgaris L.) is one of the most important crop in Brazilian agriculture. Fungi diseases are among the most restraining production factor. A test was performed aiming to analyze the spraying effect of fungicide based on nozzle type and application volume of a fungicide. The variety carioca FT-Bonito was planted in January/2001 on an experimental plot in Ponta Grossa, State of Paraná. The active ingredient azoxystrobin was sprayed using a pressurized costal spray with CO 2 . The treatments were composed by two types of nozzles (fan and empty cone) and by two methods of volume determination (manufacturer's recommendation and Leaf Area Index -LAI). The volume for the LAI method was defined by the proportionality with the maximum value of the related index, previously obtained in a greenhouse. The incidence productivity and disease severity were evaluated. The experimental design was plots with random blocks. The average values were compared by Tukey test while group of average values were compared by Scheffé test. The data showed that the treatment with fungicide was necessary for the Campos Gerais area, in the drought season harvest, mainly for the control of the angular leaf spot disease caused by Phaeoisariopsis griseola. Differe...

Trailing Boom on Fungicides Application on Wheat, Bean and Soybean

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Spray volumes for agrochemicals applied to soybean and wheat crops

“…Application technology is defined as using all scientific knowledge to provide the correct placement of the biologically active product on the target, in the required quantity, economically, and with minimum environmental contamination (Matuo 1990). Thus, the spray volume used will always be a consequence of effective application and never a pre-established condition (Ramos et al 2007), as it depends on factors such as the desired target, the type of spray nozzles, climatic conditions, plant characteristics, and the type of product, according to the mode of action of the products, translocation of agrochemicals in plants, climate, and the application method (Garcia et al 2002;Matthews 2008;Swoboda and Pedersen 2009;Antuniassi and Boller 2011;Garcia et al 2020).…”

Evaluation of the fungitoxic activity of vegetal extracts on the mycelial growth of phytopathogens

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