Two hypotheses could explain the evolution of paternal care: caring males are more attractive to females and mate more often (sexual selection); males care when the benefits in terms of offspring survival exceed the costs (natural selection). To test these hypotheses we used Phyllomorpha laciniata: females can choose whether to lay eggs on plants or on conspecifics, and the extent to which male...

The parasitoid wasp, Hyposoter horticola, parasitizes a nearly fixed fraction of its host butterfly larvae within a host metapopulation of 300–500 local populations in a 50 3 70-km area. We show, through laboratory observation, that the wasp lays eggs in fully developed larvae that have not yet hatched from the egg, constraining the period of host vulnerability to several hours out of the host’...

We assessed the ability of Trichogramma ostriniae (Peng & Chen) to locate and parasitize Ostrinia nubilalis (Hübner) eggs in crops other than corn, and we evaluated the efficacy of inundative releases of the parasitoid in two solanaceous crops, pepper and potato. Despite a greater plant surface area to search, parasitism of O. nubilalis eggs was consistently higher in sweet corn than dicotyledo...

We studied effects of parasitism by two Tiphia species (Hymenoptera: Tiphiidae) on burrowing behavior of their respective scarabaeid hosts and tested the hypothesis that parasitoid alteration of host hormones accounts for the observed behavioral change. In turf Þeld-plots, thirdinstar masked chafer grubs, Cyclocephala sp., parasitized by native Tiphia pygidialis Allen burrowed to depths of 12Ð1...

The scelionid parasitoid Trissolcus basalis (Wollaston,1858) has been detected in Belgium for the first time based on specimens reared from a parasitized egg mass of Nezara viridula (Linnaeus,1758) collected an urban garden at Sint-Amandsberg, Ghent. Identification was adult morphology and DNA barcoding. This is presently believed to be northernmost record Europe T. could consequence northward ...

In order to clarify the impacts of southern rice black-streaked dwarf virus (SRBSDV) infection on rice plants, rice planthoppers and natural enemies, differences in nutrients and volatile secondary metabolites between infected and healthy rice plants were examined. Furthermore, the impacts of virus-mediated changes in plants on the population growth of non-vector brown planthopper (BPH), Nilapa...

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...

An insecticidal exclusion method was used to assess the effect of parasitoids on level of infestation by the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), in cabbage. In field trials conducted at Rietondale, Pretoria, Gauteng Province and Brits, North-West Province, South Africa, a selective organophosphate pesticide, with systemic and contact action, dimethoate, ...

The sphingid moth larvae are voracious defoliators of several crops. present study was conducted to investigate damage Acherontia styx on Jasmine, their seasonal incidence, and bioecology. Larval instars fed jasmine leaves flowers, with the highest defoliation being 35% flower 47% during September. lifecycle consisted egg, five larval instars, pupal, adult stages. eggs were pearly white in colo...

The Asian chestnut gall wasp Dryocosmus kuriphilus, native of China, has become a pest when it appeared in Japan, Korea, and the United States. In Europe it was first found in Italy, in 2002. In 1982 the host-specific parasitoid Torymus sinensis was introduced in Japan, in an attempt to achieve a biological control of the pest. After an apparent initial success, the two species seem to have loc...