Evolutionary theory of plant defences against herbivores predicts a trade-off between direct (anti-herbivore traits) and indirect defences (attraction of carnivores) when carnivore fitness is reduced. Such a trade-off is expected in plant species that kill herbivore eggs by exhibiting a hypersensitive response (HR)-like necrosis, which should then negatively affect carnivores. We used the black...

Trichogramma wasps are tiny parasitoids of lepidopteran eggs, used extensively for biological control. They are often infected with the bacterial symbiont Wolbachia, which converts Trichogramma to an asexual mode of reproduction, whereby females develop from unfertilized eggs. However, this Wolbachia-induced parthenogenesis is not always complete, and previous studies have noted that infected f...

Trichogramma, an egg parasitoid can be used in controlling many lepidopteran pests. Therefore, it is necessary to demonstrate the capacity of these natural enemies in controlling the pest population so as to use them in biological control programs against the pest. Such an attempt was made in this particular study, where the parasitization rate of Trichogramma chilonis was tested on the eggs of...

Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the f...

Chromosomes of three chalcid wasp species from Brazil, Palmistichus elaeisis Delvare et LaSalle, 1993, Trichospilus diatraeae Cherian et Margabandhu, 1942 (both belonging to the family Eulophidae) and Trichogramma pretiosum Riley, 1879 (Trichogrammatidae), were studied using chromosome morphometrics and base-specific fluorochrome staining. The present study confirmed that these species respecti...

The study reports a field survey to determine the presence of parasitism on the leaf defoliator Hypocala andremona (Stoll) (Lepidoptera: Noctuidae) eggs, on parsimmon trees by Trichogrammatids. H. andremona eggs were sampled weekly on two branches/10 trees/orchard during the 2000/01 and 2001/02 crop seasons in Londrina, and during 2000/01crop season in Arapongas, PR, Brazil. In laboratory the e...