Abstract
The adaptation of native lepidopteran species to eucalyptus plantations reduces the productivity of this crop in Brazil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a secondary pest, frequently reported in eucalyptus plantations with population outbreaks and economic damages. Methods of biological control of this pest may include the use of the exotic pupae endoparasitoid Tetrastichus howardi Olliff (Hymenoptera: Eulophidae), reported as efficient to controlling lepidopteran pests. The parasitism of O. vesulia caterpillars and pupae by T. howardi was evaluated under controlled conditions (25 ± 1 ºC, 60 ± 20% humidity and 12:12 h L:D). Each O. vesulia caterpillar or pupae was individually placed in a flat-bottom tube with 10 and 15 females of T. howardi for 48h, respectively. The parasitoids were removed after that period, the caterpillars were fed and the pupae were maintained until emergence of the parasitoid or formation of pupae and emergence of adults of this pest. The fourth-instar caterpillars of O. vesulia, after the parasitism period, were kept in pots with Eucalyptus urophylla leaves, changed daily until the end of the experiment. A total of 40% of the caterpillars died before the pre-pupae stage, 40% reached the pupae stage and died due to inadequate adult formation and 20% generated moths, but none adult parasitoid emerged from the caterpillars. All pupae of O. vesulia were parasitized and showed emergence of parasitoids. The parasitism of O. vesulia caterpillars and pupae by T. howardi shows the potential of this natural enemy for the integrated management of this defoliator pest in eucalyptus plantations.
Highlights
Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a native moth observed in population outbreaks, damaging eucalyptus plantations in Brazil (Campos and Cure, 1993; Santos et al, 2002; Oliveira et al, 2003; Zanuncio et al, 2018)
The color, body consistency and behavior varied, and the consumption of eucalypt leaves was lower for the O. vesulia caterpillars which were parasitized by T. howardi females, while the control caterpillars kept feeding until the pupae stage
A parasitism rate of 40% by T. howardi in O. vesulia larvae and the 2% of parasitism by T. howardi in D. saccharalis larvae suggest that this life stage may poses a stronger immune response against this parasitoid (Pereira et al, 2015)
Summary
Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a native moth observed in population outbreaks, damaging eucalyptus plantations in Brazil (Campos and Cure, 1993; Santos et al, 2002; Oliveira et al, 2003; Zanuncio et al, 2018). The first report of this parasitoid in Brazil was in Diatraea saccharalis Fabricius (Lepidoptera: Crambidae) pupae obtained from corn plants (Cruz et al, 2011) and D. saccharalis pupae from sugar cane (Vargas et al, 2011) This natural enemy has parasitized caterpillars and pupae of D. saccharalis (Pereira et al, 2015) and species of the families Crambidae, Noctuidae, Plutellidae and Sphyngidae (Moore and Kfir, 1995; Cruz et al, 2011; Vargas et al, 2011; Barbosa et al, 2015), but it has not been reported for the Geometridae family, which contains some of major eucalyptus primary pests (Zanuncio et al, 1994)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have