TRICHOGRAMMATIDAE

Se revisan dos de los principales grupos de hime-nópteros parasitoides en México, los calcidoideos y los icneumonoideos. Se enfatiza particularmente en ocho familias (Aphelinidae, Encyrtidae, Eulophi-dae, Mymaridae, Pteromalidae, Trichogrammatidae, Braconidae e Ichneumonidae) y algunas especies introducidas o nativas con importancia en el control biológico de plagas agrícolas. Además, se in-cluye una síntesis sobre sus hábitos, diversidad, huéspedes, distribución y parasitismo.

Two of the main groups of parasitoid wasps in Mexico, inchenumonoids and chalcidoids, are reviewed. We discuss particularly eight families (Aphelinidae, Encyrtidae, Eulophidae, Pteromali-dae, Trichogrammatidae, Braconidae e Ichneu-monidae), and some native or introduced species important in biological control of agricultural pests. In addition, behavior, diversity, hosts, distribution and parasitism are briefly discussed.

Los tricogramátidos son una familia de insectos himenópteros de la superfamilia Chalcidoidea. Según Noyes (2016) a nivel mundial, la familia Trichogrammatidae comprende dos subfamilias, Oligositinae y Trichogrammatinae, con 97 géneros y 881 especies válidas (Aguiar et al., 2013). Pinto (2006a) y Ávila et al. (2013) registran 35 géneros para el país, sin incluir las especies. Noyes (2016) reporta 60 especies determinadas de solo 17 géneros.

Telenomus remus and Trichogramma spp. (Hymenoptera: Platygastridae, Trichogrammatidae) are known egg parasitoids of the fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) in Brazil. Reports of trichogrammatids parasitism on eggs of S. frugiperda have been relatively common, whereas the occurrence of T. remus in Brazilian crops has rarely been reported. Consequently, literature that gives insights about the interspecific competition among individuals of T. remus and Trichogramma spp. in field is very scarce. Here we report the simultaneous occurrence of T. remus, Trichogramma pretiosum and Tr. atopovirilia on eggs of the FAW in maize (Piracicaba, São Paulo, Brazil). Our findings imply that these three egg parasitoid species were engaged in exploitative competition (indirect interaction, where the depletion of resources by one species prevents the other access to it) towards eggs of S. frugiperda. Moreover, given the emergence of combinations of two and three of these parasitoid species from a single egg mass, our data strongly suggest that T. remus, Tr. pretiosum and Tr. atopovirilia were also engaged in interference competition (direct interactions among adults and/or immature individuals resulting in behavioral changes or even death of individuals). Both exploitative and interference competitions may affect the population dynamics of parasitoids with consequences to the biological control of pests. Hence, the present findings highlight the importance of determining the outcome of competition among T. remus, Tr. pretiosum and Tr. atopovirilia towards eggs of S. frugiperda in laboratory and field studies.

By means of an international project, Argentinian and Italian researchers are carrying out joint research to study biological and ecological aspects of Tuta absoluta biological control.
This paper lists indigenous natural enemies reported for T. absoluta, as well as the current results on T. absoluta egg and larval parasitoids in both countries. Parasitoid species that
conformed to different guilds are shown to coexist in cropping conditions, and some show positive characteristics as potential biocontrol agents against T. absoluta by means of augmentative
releases. Future laboratory and field evaluations of the efficacy of biological control programs in Argentina and Italy are proposed.