MANEJO DE CIGARRINHA DO MILHO (Dalbulus maidis) COM O USO DE PRODUTOS BIOLÓGICOS

Abstract

Controlling various agriculturally significant pests is a current challenge due to the intensive use of insecticides, leading primarily to the selection of pest populations and vectors resistant to multiple active ingredients. Alternative methods, such as biological control using microorganisms, are gaining prominence for managing agricultural pests. This study aimed to evaluate the effectiveness of biological products—fungi and bacteria—in controlling the corn leafhopper (Dalbulus maidis), addressing the related stunt complex and maize productivity. The experiment was conducted at CentroAgro Pesquisa's experimental area in Rio Verde, Goiás. The experimental design used was a randomized block design with five treatments and four replications for two maize sowing periods. The treatments were: Treatments 01 Control: No treatment applied, 02 Isaria fumosorosea (strain ESALQ 1296) + Aschophillum nodosum (seaweed), 03 Beauveria bassiana (IBCB 66) + Cordyceps javanica, 04 Isaria fumosorosea + Beauveria bassiana (IBCB 66), 05 Neem oil (azadirachtin A) + Pseudomonas fluorescens and Pseudomonas chlororaphis. applied at the recommended commercial doses. The first application was performed when seedling emergence coincided with an average of three corn leafhoppers per plant. Evaluations of plants exhibiting stunt symptoms were conducted, and data were expressed as percentages. Ear height was assessed for five consecutive plants in each experimental plot. Bio-insecticide applications were conducted with a pressurized backpack sprayer, and pre-harvest evaluations for both periods were done manually, followed by threshing and weighing of grains, adjusting their moisture content. Data were analyzed using ANOVA (F-test), and Tukey's test was applied when necessary at a 5% significance level. The tested products proved effective in controlling the corn leafhopper by promoting healthier and taller maize plants, greater grain weight, and higher productivity across both sowing periods.