Seleção de atrativos alimentares e toxicidade de inseticidas para o manejo da broca-pequena-do-tomateiro

Abstract

Resumo -O objetivo deste trabalho foi avaliar a preferência alimentar, o limiar de ingestão e o efeito tóxico de inseticidas associados a atrativos, em adultos de Neoleucinodes elegantalis. Foram testados os atrativos: melado e mel a 10%, extrato hexânico de frutos verdes de tomate a 0,4%, sacarose a 5%, suco de laranja e suco de uva a 30%, vinagre de vinho tinto a 10% e proteína hidrolisada a 5%. Com base no teste de preferência alimentar, foram selecionados os atrativos sacarose, melado, mel e suco de laranja, para determinar o limiar de concentração capaz de estimular a alimentação de adultos de N. elegantalis. Foi testado o efeito tóxico de inseticidas associados ao mel a 10%. A sacarose e o mel apresentaram o melhor resultado em relação ao número de pousos e ao tempo de pouso e de alimentação de adultos de N. elegantalis. Os inseticidas não afetaram negativamente a atração pelo alimento dos adultos de N. elegantalis. Carbaril, cartape, deltametrina, fenpropatrina, indoxacarbe, lambda-cialotrina e lufenurom provocaram 100% de mortalidade em adultos (machos + fêmeas), após 24 horas de exposição, e mostraram-se promissores para o uso em iscas tóxicas.Termos para indexação: Neoleucinodes elegantalis, controle comportamental, iscas tóxicas, limiar de resposta. Selection of attractive food sources and toxicity of insecticides in tomato fruit borer managementAbstract -This work aimed at evaluating the food preference, the threshold of food intake and the toxic effect of insecticides associated with attractive food sources on adults of Neoleucinodes elegantalis. The following attractive food sources were tested: molasses and honey at 10%, hexanic extract of green tomato fruits at 0.4%, sucrose at 5%, orange and grape juice at 30%, red wine vinegar at 10%, and hydrolyzed protein at 5% concentration. Based on the food preference test, sucrose, molasses, honey, and orange juice were selected to determine the threshold concentration capable of stimulating feeding in N. elegantalis adults. The toxic effect of insecticides added to honey at 10% was also tested. Sucrose and honey had the best results in terms of number of landings, landing time, and feeding time of adults of N. elegantalis. The insecticides did not affect negatively the attraction of N. elegantalis adults to the food sources. Carbaryl, cartap, deltamethrin, fenpropatrin, indoxacarb, lambda-cyhalothrin, and lufenuron caused 100% mortality of adults (males and females), after 24 hours of exposure, which suggests that they are promising for use in toxic baits.

Integrated management of tomato fruit borer (Neoleucinodes elegantalis)

“…In relation to ovicidal effect, etofenprox, fenpropathrin and methomyl proved to be a promising alternative for controlling N. elegantalis larvae before they could penetrate the fruit. Azadirachtin (NeemPro) had the highest slope of a curve dosage-mortality of N. elegantalis eggs compared to other insecticides, meaning that a small increase in the concentration causes significant increases in mortality; however, deltamethrin (Decis ® 250 CE) was 144.58 times more toxic than the neem-based insecticides tested (França et al, 2009a).…”

“…Research conducted with adult N. elegantalis found that mortality caused by lufenuron and deltamethrin associated with a 10% honey solution increased directly with the evaluation periods (0, 0.5, 1, 2, 12 and 24 h after exposure) for males, females and adults (male and females), reaching 100% mortality at 2 h of observation (França et al, 2009b).…”

“…Four plants with about 10 to 15 fruits were placed in each cage. Plants were sprayed with the insecticides lufenuron (Match ® EC), deltamethrin (Decis ® ) and indoxacarb (Rumo ® ) at commercial concentrations, associated with (França et al, 2009b). The application was carried out with a manual backpack sprayer with a light-jet cone nozzle.…”

“…Host-plant location is not only related to feeding, but also to oviposition site selection. In Lepidoptera, finding the oviposition site is mediated by the presence of one or more substances that form the specific volatiles or blends of volatiles of the host (França et al, 2009a). The alteration of the plant natural aroma by applying nonspecific volatiles can promote rejection.…”

Effect of Food Attractants and Insecticide Toxicity for the Control of Spodoptera frugiperda (Lepidoptera: Noctuidae) Adults

“…For the choice of an appropriate attraction, some factors should be considered, such as: cost, ease of application, attractiveness of adults, especially females and landing time associated with feeding, because the greater the contact of the sensory organs of insects with the bait, the greater the effectiveness of the associated insecticide (França et al, 2009).…”