INFLUÊNCIA DE ADJUVANTES DE CALDA NO DEPÓSITO EM APLICAÇÕES AÉREAS E TERRESTRES

A ferrugem asiatica atualmente e a principal doenca da cultura da soja, apresentando dificil controle por iniciar no terco inferior da planta. Novas tecnologias como adjuvantes tem sido desenvolvidas para aumentar a deposicao das gotas nos alvos, contudo ha carencia de informacoes sobre a eficiencia da acao esperada para estes produtos. O objetivo deste trabalho foi avaliar a capacidade do adjuvante TA-35 aumentar a deposicao de caldas de fungicidas com ou sem oleo mineral em aplicacoes aereas e terrestres. O delineamento utilizado foi um fatorial 3x2, tres caldas de pulverizacao com Priori Xtra (suspensao concentrada contendo azoxistrobina 200 g L -1 + ciproconazol 80 g L -1 ) em mistura com os adjuvantes Nimbus (concentrado emulsionavel contendo hidrocarbonetos alifaticos, 428 g L -1 ) e TA-35 (concentrado soluvel contendo lauril eter sulfato de sodio, tensoativos, sequestrantes e emulsificantes), alem do corante Azul Brilhante (FD&C no 1) como marcador, em aplicacoes por vias aerea e terrestre. Nas aplicacoes terrestres utilizou-se o volume de calda de 50 L ha -1 , pontas TXA 8002 VS, e nas aereas 15 L ha -1 , atomizador Turboaero, ambos aplicando gotas finas. Os alvos utilizados para captacao das gotas foram lâminas de vidro. Apos a extracao do corante dos alvos por lavagem com agua destilada, as amostras foram analisadas por espectrofotometria, possibilitando quantificar o deposito de corante em cada lâmina. Um estudo para avaliar possiveis perdas do marcador por degradacao ou retencao tambem foi feito. A analise comparativa dos tratamentos foi feita pelo metodo estatistico “Intervalo de Confianca para Diferencas entre as medias” com grau de confianca de 95% (IC95%). Houve degradacao ou retencao do marcador entre os processos de aplicacao das caldas e a leitura das amostras. Apesar do uso do TA-35 ter aumentado as medias de deposicao para as aplicacoes aereas e terrestres, nao houve diferencas significativas entre os tratamentos para cada via de aplicacao. Desta forma, outros parâmetros ou estudos complementares devem ser considerados para justificar a viabilidade de uso deste adjuvante. PALAVRAS-CHAVE: coletores, fungicidas, tecnologia de aplicacao. ADJUVANTS ON SPRAY DEPOSITION OF AERIAL AND GROUND APPLICATIONS ABSTRACT: The Asian rust currently is the main disease of soybean culture, having as characteristics the difficult control, by start at the bottom of plants where penetration of the droplets is harder. The fine droplets has been used with the intention of improve the penetration and increase efficiency of agrochemicals, but that are losses by drift easily. New products have been developed to increase deposition of the drops at targets. The aim of this work was evaluate the TA-35 capacity to improving the deposition of fungicides spray solution with or without mineral oil by aerial and ground applications. Was used a factorial 3x2, three spray solutions composed by Priori Xtra (concentrated suspension of azoxystrobin 200 g L -1 + cyproconazole 80 g L -1 ) mixed with adjuvants, Nimbus (emulsifiable concentrate containing aliphatic hydrocarbons 428 g L -1 ) and TA-35 (soluble concentrate containing sodium lauryl ether sulfate, surfactants, sequestering agents and emulsifiers), in aerial and ground applications. In ground applications was used 50 L ha -1 , TXA 8002 VS spray nozzles and on aerials was used 15 L ha -1 , Turboaero atomizer, both applying fine droplets. Was utilized the Brilliant Blue (FD & C n. 1) tracer to determine the deposits. There were used glass slides as targets to collect spray droplets. After to extract the tracer of the targets using distilled water, the samples were analyzed by spectrophotometry, thereby was possible quantify the tracer deposited on each glass slide. A study to evaluate possible losses of the tracer by degradation or retention also was done. The comparative analysis of treatments was done by statistical method "Confidence Interval for Differences Between the Averages" with 95% of confidence degree (IC95%). There was degradation or retention of the tracer between the processes of application of the droplets and the processing of the samples. The deposition averages with the presence of TA-35 were greatest for both sprayers however, there were not significant differences among the treatments. The viability of TA-35 use may consider other parameters or complementary studies. KEYWORDS : application technology, collectors, fungicides.