Egg parasitoids face unique developmental constraints. First, they have exceptionally limited resources to support themselves and their siblings through three life stages. Second, they develop within the physiological system of another species, which they modify to their own ends. We examined how these constraints affect the metabolic physiology of egg parasitism, and whether parasitoids retool...

Early attempts at the biological control of the pyralid borer Eldana saccharina Walker were discussed in a paper presented at the Congress of the South African Sugar Technologists' Association in 1979. Since then further introductions of both egg and larval parasitoids have been made and include: Trichogrammatoidea eldanae Vigianni, Trichogramma sp and Telenomus applanatus Bin & Johnson (from W...

This paper describes a new adaptation of a cognitive vision system in biology field. Our goal is to monitor Trichogramma activities from image sequence. More precisely we aim at recognizing several scenarios of the parasitoid behavior when it parasites the eggs of the Mediterranean flour moth Ephestia kuehniella Zeller (crops-harmful butterfly). The main advantage of our current work is the use...

Trichogramma are facultative gregarious egg parasitoids that attack a wide range of lepidopterous eggs. Because hosts in which parasitoids develop vary in terms of available food, the progeny produced by parasitoid females vary in size and fitness. While one might expect that the developmental rate and emergence rhythm should be similar for all individuals reared under the same environmental co...

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...