6533b860fe1ef96bd12c3a17

RESEARCH PRODUCT

Inter and intra-guild interactions in egg parasitoid species of the soybean stink bug complex

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Abstract – The objective of this research was to evaluate the parasitism behavior of Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae) oneggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), in no choice and multiple choice experiments. For allparasitoid species, the results demonstrated the existence of a main host species that maximizes thereproductive success. The competitive interactions among the parasitoid species were investigated inexperiments of sequential and simultaneous release of different combinations of parasitoid pairs on thehosts N. viridula, E. heros and A. aseadum. Exploitative competition was observed for egg batches atthe genus level ( Telenomus vs. Trissolcus) and interference competition at the species level ( T. basalisvs. T. urichi). Trissolcus urichi was the most aggressive species, interfering with the parasitism ofT. basalis. Generally, T. basalis showed an opportunistic behavior trying to parasitise eggs after T. urichihad abandoned the egg batch. The selection of parasitoid species for use in augmentative biologicalcontrol programs should take into account the diversity of pentatomids present in soybean in additionto the interactions among the different species of parasitoids.Index terms: parasitism, host-parasite relations, biological competition, pest control methods.Interacoes inter-guilda e intra-guilda entre especies de parasitoides de ovosque atacam o complexo de percevejos da sojaResumo – O objetivo desta pesquisa foi avaliar o comportamento de parasitismo de Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae)em ovos de Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood e Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), em experimentos de multipla escolha e sem escolha dehospedeiros. Todas as especies de parasitoides testadas demonstraram possuir um hospedeiro quemaximizou a sua capacidade reprodutiva. As interacoes competitivas entre especies de parasitoidesforam investigadas mediante experimentos de liberacao sequencial e simultânea de diferentescombinacoes de pares de especies de parasitoides em N. viridula, E. heros e A. aseadum. Competicaopor exploracao foi observada a nivel de genero ( Telenomus vs. Trissolcus) e competicao por interferenciaa nivel de especie (T. basalis vs. T. urichi). A especie mais agressiva foi T. urichi, interferindo noparasitismo de T. basalis. Geralmente, T. basalis apresentou um comportamento oportunista tentandoparasitar os ovos apos T. urichi ter abandonado os lotes de ovos. A selecao de especies de parasitoidespara uso em programas de controle biologico aumentativo deve considerar a diversidade depentatomideos presentes na soja, alem das interacoes entre as especies de parasitoides que serao liberadas.Termos para indexacao: parasitismo, relacao parasita-hospedeiro, competicao biologica, metodos decombate as pragas.