Controle de Quesada gigas (Hemiptera: Cicadidae) pela aplicação de nematoides entomopatogênicos e compatibilidade com alguns produtos fitossanitários em cafeeiro

Abstract

The coffee production in Brazil is quite significant, accounting for much of the world production. Among the species of cicadas, Quesada gigas stands out, considered one of the main pests, due to its greater size and causing more serious damage to plants. As a way of controlling these insects is still widely used chemical control with several products registered and available for the culture, but with undeniable contaminants and residual effects, which supports the use of diverse and sustainably methosds to mitigate the application of biocides, such as entomopathogenic nematodes. Thus, the aims of this study were to analyze the persistence of entomopathogenic nematodes of the genera Heterorhabditis and Steinernema, aiming to control the cicada nymphs, to test the efficiency of different methods of application in the field and check for compatibility between the chemicals used and the nematodes. An experiment was conducted on coffee trees in the city of Lavras/MG with Catucaí coffee adult plants of six years old, with randomized block design consisting of four blocks with six treatments, six plants in each plot. The results demonstrated that entomopathogenic nematodes are persistent in the environment, being recovered until 30 and 60 days after application, and the entomopathogenic nematode Heterorhabditis sp. JPM4 was more persistent in the field under adverse conditions. The second experiment was conducted with adult plants of 15 years old in the experimental area free of chemical insecticides for about 10 years, on a randomized block design consisting of four blocks with seven treatments, six plants in each plot. The results reinforced the persistence and efficiency characteristics obtained in the previous experiment, in relation to the entomopathogenic nematode Heterorhabditis sp.JPM4. Finally, it was evaluated aspect related to the compatibility of chemical pesticides used in coffee plantations with entomopathogenic nematodes, in an experiment according to the protocol of the IOBC, evaluating the viability and infectivity of nematodes exposed to aqueous solutions of products. None of the pesticides affected significantly the infectivity of the nematodes, and the products and Impact 125® and Alto 100® were that most damaged the viability of entomopathogenic nematodes.