Effect of Wolbachia on the Survival and Reproduction of Trichogramma kaykai Pinto & Stouthamer (Hymenoptera: Trichogrammatidae)

Abstract

Efeito de Wolbachia na Sobrevivência e Reprodução de Trichogramma kaykaiPinto & Stouthamer (Hymenoptera: Trichogrammatidae) RESUMO ABSTRACT -Parthenogenetic inducing Wolbachia infections are particularly common in the genusTrichogramma, but the influence of the microrganism on parasitoids' fitness has received relatively little attention. The aim of this study was to determine the effects of the bacteria on the survival and reproduction of Trichogramma kaykai Pinto & Stouthamer, comparing an infected line (thelytokous) with an antibiotically cured (arrhenotokous) line, both reared on Trichoplusia ni Hübner eggs. Cured wasps produced significantly more progeny and more daughters than Wolbachia-infected wasps. Significantly more wasps emerged per host when parasitized by the arrhenotokous females than by the thelytokous females. Cured females, however, lived significantly less than infected females. Eggs of cured females matured faster than infected ones.

CanWolbachiainfection improve qualitative characteristics ofTrichogramma brassicaereared on cold stored eggs of the host?

“…Similarly, Wolbachia infection was found to negatively affect the fecundity of T. brassicae. The reduced fecundity of Wolbachia-infected lines has been previously reported for different Trichogramma species in both laboratory and greenhouse conditions (Stouthamer & Luck 1993;Wang & Smith 1996;Silva 2000;Hohmann et al, 2001). Apparently, differences in the ovarian development underlies the differential fecundity of Wolbachia-infected and uninfected strains (Wang & Smith 1996).…”

Adult feeding and mating effects on the biological potential and parasitism of Trichogramma pretiosum and T. acacioi (Hym.: Trichogrammatidae)

“…There are different kinds of Trichogramma release techniques (Pinto, et al 2003) but for all of them, it is crucial to offer a source of food such as honey droplet for example to the parasitoid. These parasitoids normally feed on nectar and pollen of wild flowers in natural conditions (Andow and Rish, 1987;Wellinga and Wysoki, 1989;Hohmann et al, 2002). However, the energy and time consumed in this activity may be saved and used to increase the parasitism by offering an artificial food supply close to the releasing points in the field.…”

“…This parameter was not evaluated for T acacioi because mated females without food did not lay eggs (Table 1). However, only mated females had sex ratio different from zero for both species showing the great importance of mating to have female descendants ( by arrhenotoky, with haploid males being originated by unfertilized eggs and diploid females from fertilized ones (Hohmann et al, 2002). Mated parasitoid females keep the male sperm to manipulate the sex ratio of their descendents by controlling the sperm access to their eggs during laying (Boivin et al, 2004;Doyon and Boivin, 2005).…”

“…The results showed the importance to use matted females at releases, mainly when females descendants were needed. However, some species of the genus Trichogramma present reproduction by thelytoky where both fertilized and unfertilized eggs originate diploid females (Hohmann et al, 2002). The female longevity was influenced by feeding and indirectly by mating for both species.…”

Does mating interfere in the biological characteristics of a population of Trichogramma pretiosum?

“…In arrhenotokous Trichogramma species, mating is an important factor to consider for the successful use of these species in the field, since unfertilized eggs produce male individuals (Pratissoli et al 2009, Farrokhi et al 2010, which can compromise the maintenance of the parasitoid in the field. On the other hand, mating in thelytokous species is not essential to ensure a large number of female descendants, since both fertilized and unfertilized eggs will produce females (Hohmann et al 2002). Thus, field releases of thelytokous populations can be more efficient when compared to arrhenotokous populations (Stouthamer 1993).…”