Insecticide Susceptibility of <I>Euschistus heros</I> (Heteroptera: Pentatomidae) in Brazil

Abstract

Euschistus heros (F.) (Heteroptera: Pentatomidae) is the most prevalent stink bug pest in Brazil, and populations can be difficult to manage using organophosphates or endosulfan. Because E. heros is difficult to rear in the laboratory, no baseline insecticide susceptibility data have been published. Therefore, we conducted dose-mortality studies using field-collected insects, and, using the results from the dose-mortality studies, we surveyed susceptibility to acephate, methamidophos, and endosulfan in populations from southern and central Brazil. In addition, esterase activity was evaluated among populations as these enzymes have been related to organophosphate resistance. Finally, newer chemistries were evaluated for E. heros population management in small-plot field studies. In the dose-mortality bioassays, variation in susceptibility to methamidophos and endosulfan among populations was significant, but the variation in susceptibility to acephate was not. The population from Londrina (at the Embrapa Soybean Research Station, northern Parana state) was among the most susceptible, whereas the population from Pedrinhas Paulista (southwestern Sao Paulo state) was among the least susceptible. Significant variation among populations was observed in esterase activity with the population from Pedrinhas Paulista having the highest esterase levels and the population from Londrina having among the lowest levels. To survey populations, we used the dose-mortality data for the Londrina population (because it was, consistently, one of the most susceptible populations) to estimate the insecticide concentration that killed 99% of the population (LC99). The corresponding doses were 5.9 microg (AI) of acephate adult(-1), 0.7 microg (AI) methamidophos adult(-1), and 1,600 microg (AI) endosulfan adult(-1). The survey data confirmed the data from the dose-mortality bioassays in that the population from Pedrinhas Paulista was identified as one of the least susceptible and the population from Londrina was one of the most susceptible. The field tests confirmed that older chemistries provided minimal control (< 50% control), whereas the products containing mixtures of pyrethroids and neonicotinoids provided better control (> 60%).

Sequential sampling of Euschistus heros (Heteroptera: Pentatomidae) in soybean

“…However, populations of this pentatomid are difficult to manage using organophosphates (methamidophos, acephate, chlorpyrifos, and monocrotophos) or cyclodiene endosulfan (Sosa-Gómez et al, 2009). Consequently, control strategies are based on spraying using a limited group of insecticides (Sosa-Gómez et al, 2001).…”

Identification and functional characterization of esterases in Euschistus heros (Hemiptera, Pentatomidae) and their relationship with thiamethoxam and lambda-cyhalothrin

“…Sosa-Gómez et al (2009) evaluated the activity of esterases in populations of E. heros in the Brazilian states of Paraná and São Paulo using α-naphthyl acetate as a substrate, and found significant variation in esterase activity in these populations. The present study also found six different types of esterase in these insects that are capable of hydrolyzing α-naphthyl acetate.…”

Biological Parameters of Euschistus heros (F.) (Heteroptera: Pentatomidae) and its Susceptibility to Entomopathogenic Fungi When Fed on Different Diets

“…Among the species most frequently found on soybeans, Euschistus heros (F.) (Heteroptera: Pentatomidae) are considered the most relevant pests in the main productive regions of Brazil (Sosa-Gómez et al 2009). The large populations of these insects and the lack of action-level usage of insecticides frequently leads to the indiscriminate use of chemical products to control of these insects (Corrêa-Ferreira 2005).…”