Horários de aplicação localizada ou em área total e uso de adjuvantes para o controle de Spodoptera frugiperda (Lepidoptera: Noctuidae) na cultura do milho

• Ano de defesa: 2014
• Autor(a) principal: Soares, Ariane Morgana Leal [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Milho; Milho - Doenças e pragas - Controle; Lagarta; Defensivos vegetais - Tecnologia de aplicação; Pulverização; Spraying
• Link de acesso: http://hdl.handle.net/11449/113786

The larval stage of Spodoptera frugiperda (Lepidoptera: Noctuidae) is the major cause of yield losses in maize. The aim of this study was to evaluate the control of S. frugiperda, during the first infestation, in day and nighttime spraying directed to maize plants whorl and in total area with insecticide spraying liquids supplemented or not by adjuvant as well as analyze physical characteristics of surface tension and contact angle, droplets diameter and volumetric distribution for the two modes of application. The research at field conditions has involved two modes of application (directed to the whorl of plants and to total area), two times (8 a.m. and 8 p.m.), three insecticide spraying liquids (only insecticide, insecticide with nonifenol and insecticide with oil) and a treatment without application following a triple factorial (2x2x3)+1, in a randomized block design with four replications. Sowing was done in seasons 2012/13 and 2013/14, the factors evaluated were larvae alive after application (4, 8 and 12 days) and dry matter of maize plants (g.parcela-1). The surface tension and contact angle were obtained in tensiometer. The droplets diameter was measured by a laser analyzer and the volumetric distribution on patternator. The same spraying liquids from the field experiment were used and compared with water only (same as used for spraying), and ultrapure water, and two models of spray nozzles DG95015 and LD110015. Data were subjected to analysis of variance by F test and the means were compared by Tukey test at 5% probability. It was obtained better control of the insect by the nocturnal directed spraying, regardless of the spraying liquid used, with smaller loss dry matter weight. The addition of adjuvants to insecticide spraying liquids increased wetting and the diameter of sprayed droplets for the two nozzle models, and the volumetric distribution was equivalent for the two application ...