Natural parasitism of Hexacladia smithii Ashmead (Hymenoptera: Encyrtidae) on Euschistus heros (F.) (Hemiptera: Pentatomidae): new record from Mato Grosso State, Brazil

Abstract

The neotropical stink brown bug, Euschistus heros (F.) (Hemiptera: Pentatomidae), is an insect pest to soybean crops in Mato Grosso State, Brazil. In this region, synthetic insecticides are frequently used for insect control. An alternative to the indiscriminate use of insecticides is the biological control with parasitoids. Thus, the objective of this study was to conduct the survey of parasitoids that use E. heros adults as hosts. Random samples were conducted during the harvests of 2009/10 and 2010/11 in two farms that produce soybean (conventional system) in Tangará da Serra, Mato Grosso State, Brazil. The total number of collected E. heros was: 297 (Field 1) and 293 (Field 2) in 2009/10 and 295 (Field 1) and 376 (Field 2) in 2010/11. Of these, 1.50 (Field 1) and 13.99% (Field 2) were parasitized in 2009/10 and 8.47 (Field 1) and 7.45% (Field 2) in 2010/11. The parasitoids found were Hexacladia smithii Ashmead (Hymenoptera: Encyrtidae) in both fields. This is the first record of parasitism in E. heros adults in the state of Mato Grosso, Brazil.