Parasitism and Development of Tetrastichus howardi (Hymenoptera: Eulophidae) in Immature Spodoptera frugiperda (Lepidoptera: Noctuidae)

Abstract

Tetrastichus howardi (Olliff, 1893) (Hymenoptera: Eulophidae) is an endoparasitoid mainly of Lepidoptera. Its potential as a biological control agent has been investigated for several agricultural and forestry species in different countries. The objective of our study was to evaluate the biological characteristics of T. howardi in larvae, prepupae and pupae of Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae), under laboratory conditions. The first bioassay was performed with S. frugiperda larvae in the fifth and sixth instar and prepupal phases, which were exposed to the parasitism of 7 female T. howardi for 24 h. The second bioassay was conducted with S. frugiperda pupae, with parasitism allowed for 24 h, at six parasitoid of T. howardi densities, for one host pupa of S. frugiperda (1, 7, 14, 21, 28 or 35 parasitoids: 1 host). The parasitism of T. howardi in S. frugiperda larvae was confirmed by larval mortality and the emergence of parasitoid descendants. Female T. howardi parasitized and emerged from S. frugiperda larvae of fifth and sixth instars, prepupae, and pupae under laboratory conditions, which is the first record of such in the literature.