Tachinid parasitoids of the adult stage of phytophagous stink bugs: a vacant niche in Piezodorus guildinii (Hemiptera: Pentatomidae).

BARAKAT, M.C.; DÍAZ, SOFÍA PILAR; LILJESTHRÖM, G.G.; CINGOLANI, M.F.

Fortaleza (Brasil)

Congreso; XXVIII Congresso Brasileiro de Entomologia; 2022

Sociedade Brasileira de Entomologia (SBE)

Phytophagous hemipterans of the Pentatomidae family are pests of several crops. Among them, Piezodorus guildinii and Nezara viridula are two of the most harmful ones. Two guilds of natural enemies attack them: the oophagous parasitoids and those of the adult stage. Adults of P. guildinii are not commonly parasitized, unlike N. viridula, which is frequently attacked by Trichopoda pennipes (Diptera: Tachinidae), suggesting a vacant niche on that pest. Only a few references are known regarding the unusual occurrence of parasitism of adults of P. guildinii by tachinid flies. Under particular circumstances a parasitoid may include a non-preferred species among its potential hosts. For example, as the life expectancy of a parasitoid decreases, its selectivity also decreases, lowering the quality threshold below which hosts are rejected. In this work, the potential of P. guildinii as a host for T. pennipes females of different ages was evaluated: young and old parasitoids (1 and 5 days old, respectively). Parasitism was not significantly different among treatments, although the proportion of hosts accepted by old female parasitoids was higher than the proportion accepted by young females. Even though progeny’s emergence rate was low in both cases, we obtained a viable F1 generation. These data, although preliminary, indicate that T. pennipes attacks P. guildinii and is able to develop on this host, resulting of interest for the design of integrated management strategies for this pest, mainly in a scenario where N. viridula populations are decreasing in density and P. guildinii is becoming more abundant.