Eficácia do uso de diferentes modos de ação de inseticidas para controle de lagartas na cultura do milho

Abstract

Corn (Zea mays L.) is one of the main agricultural crops in Brazil, due to its wide adaptability to the country's diverse climatic conditions and its relevance as a source of nutrition for both humans and animals. Its versatility allows cultivation in various seasons throughout the year, which, in turn, favors the occurrence of pests and pathogens, major factors responsible for yield reduction. Among the pests of greatest economic importance are the caterpillars Spodoptera frugiperda, Helicoverpa armigera, and Helicoverpa zea (Lepidoptera: Noctuidae), which cause direct damage to the photosynthetically active area of the plant and significantly reduce grain yield. To mitigate the losses caused by these insects, it is essential to adopt integrated pest management (IPM) strategies, with emphasis on the use of insecticides with different modes of action, both chemical and biological. This study aimed to evaluate the efficacy of different chemical and biological insecticides in managing caterpillars in corn crops. The experiment was conducted in Uberlândia, Minas Gerais (MG), during the first growing season of the 2024/2025 agricultural year, using a randomized block design (RBD) with eight treatments and eight replications. The commercial hybrid Supremo Viptera 3 was used. The control treatment received no insecticide applications, while the other treatments involved different combinations of chemical and biological products. The evaluated variables were final stand, plant height, ear insertion height, and grain yield. Statistical analyses were performed using the SISVAR software. Analysis of variance and Tukey’s test at a 5% significance level were applied. The results showed that treatments with different insecticide modes of action were effective in controlling chewing insects, contributing to the maintenance of the crop's productive potential. The combination of chemical and biological insecticides showed promising results, although without statistically significant differences compared to the other chemical treatments. Treatments based on indoxacarb and the combination of chlorantraniliprole + chlorfenapyr stood out in terms of yield. However, considering the complexity of pest management and the risk of resistance development, further studies are recommended to enhance integrated pest control strategies.