Monitoramento do percevejo marrom Euschistus heros (Hemiptera: Pentatomidae) por feromônio sexual em lavoura de soja

Abstract

Resumo -O objetivo deste trabalho foi avaliar a eficiência das formulações septo de borracha e lure do feromônio sexual do percevejo marrom Euschistus heros e compará-la ao método do pano de batida, para o monitoramento dessa praga em lavoura de soja. Os tratamentos foram: feromônio em septo de borracha, feromônio em lure e amostragem com pano de batida. As amostragens foram realizadas semanalmente durante a fase reprodutiva da soja (dez semanas). Para estimar a densidade populacional de percevejos e compará-la à captura nas armadilhas de feromônio, foram efetuados quatro panos de batida por semana em todas as parcelas; além disso, foi determinado o número de percevejos capturados nas armadilhas por semana. Os danos provocados pelos percevejos nas sementes foram analisados pelo teste de tetrazólio. As formulações do feromônio foram eficientes na captura de E. heros, e a formulação em lure capturou mais percevejos. O controle precoce da população, indicado pelo nível de controle nas armadilhas com feromônio, resultou em sementes com maior qualidade do que as provenientes das parcelas monitoradas pelo pano de batida. Assim, as armadilhas com feromônio são mais eficientes que o pano de batida para o monitoramento das populações de percevejos durante a fase crítica do ataque deste inseto nas lavouras de soja.Termos para indexação: armadilha de feromônio, pano de batida, percevejo marrom, qualidade das sementes. Monitoring of the brown stink bug Euschistus heros (Hemiptera:Pentatomidae) with sex pheromone in soybean fieldsAbstract -The objective of this work was to evaluate the efficiency of rubber septum and lure formulations of the brown stink bug Euschistus heros sex pheromone and to compare it with the shake cloth method for monitoring this pest in soybean fields. The treatments were: pheromone in rubber septum, pheromone in lure, and sampling with shake cloth. Samples were taken weekly during the soybean reproductive stage (ten weeks).To estimate bug population density and compare it with the capture in pheromone traps, four shake clothes per week were carried out in all plots; in addition, the number of bugs captured in traps was determined weekly. Damage caused by bugs in seeds was evaluated using the tetrazolium test. Pheromone formulations were effective in capturing E. heros, and the lure formulation captured more bugs. Early population control, indicated by the level of control in the pheromone traps, resulted in seeds with higher quality than those from plots monitored with shake cloth. Therefore, pheromone traps are more efficient than the shake cloth for monitoring stink bug populations during the critical phase of the bug attack in soybean fields.

Temporal variation and spatial distribution of Euschistus heros (Hemiptera: Pentatomidae) during the soybean grain formation period

“…The temporal variation of adults was in line with Silva et al (2014), who found the stabilization of adult growth when the plants were at the grain filling stage (R5 to R5.4).…”

“…The nymph population grew throughout the evaluations, surpassing the number of adults when the soybean was at R6 (Figure 1), a moment characterized by full and green grains. This fact is corroborated by Silva et al (2014), who observed an increase in the number of nymphs after the grain formation and filling period, which may be explained by the appearance of pods, making soybean more nutritionally suitable for reproduction, and increasing the number of nymphs (Fonseca et al, 2017).…”

Attractive food in the sampling and seasonality of insects in soybean-oats succession

“…Sampling defines the population of insects present in a particular area of cultivation, being a presupposition for decision making under the precepts of Integrated Pest Management (Guedes et al, 2006;Riffel et al, 2012). Different techniques to know the population of a certain species of insect-plague or natural enemy are spent by technical assistants and producers, the most known and used are: direct observation, pinworm, entomological net, light trap and sexual pheromone trap (Silva et al, 2014;Pasini et al, 2015;Storck et al, 2016;Garlet et al, 2016).…”