The western tarnished plant bug Lygus hesperus Knight (Heteroptera: Miridae), a major pest of cotton and other key economic crops, was tested for its sensitivity to population density during nymph and adult stages. Nymphs reared to adulthood under increasing densities in laboratory conditions exhibited incremental delays in maturation, heightened mortality rates, and reductions in body mass and...

We introduce two criteria for judging “goodness” of the result when combining preference relations in information systems: completeness and consistency. Completeness requires that the result must be the union of all preference relations, while consistency requires that the result must be an acyclic relation. In other words, completeness requires that the result contain all pairs appearing in th...

Larvae of Aedes albopictus Skuse typically inhabit natural and artificial containers. Since these larval habitats are replenished by rainfall, Ae. albopictus may experience increased loss of immature stages in areas with high levels of rainfall. In this study, we investigated the effects of rainfall and container water level on population density, and oviposition activity of Ae. albopictus. In ...

Egg parasitoids in the family Eulophidae (Hymenoptera) are an important part of the community of insects attacking neotropical leaf beetles in the subfamily Cassidinae. We present a phylogeny of 24 species of oophagous Eulophidae, using the 28S rDNA, the ITS2 rDNA and the cytochrome b genes, applying the NJ, MP, ML and Bayesian tree reconstruction methods on each data set. We ask whether the ph...

Understanding the size of clutches produced by only one parent may require a game-theoretic approach: clutch size may affect offspring fitness in terms of future competitive ability. If larger clutches generate smaller offspring and larger adults are more successful in acquiring and retaining resources, clutch size optima should be reduced when the probability of future competitive encounters i...

Blocks of expanded polystyrene (EPS) were placed in a variety of habitats to investigate their potential as an egg-collection device for container-dwelling Aedes and Ochlerotatus species. Eggs from Ochlerotatus japonicus, Oc. triseriatus, Oc. hendersoni, and Aedes albopictus were collected with EPS floats. The float provides an inexpensive, low-maintenance alternative to the Centers for Disease...

The structural differentiation of rostrum in male and female adults of rice weevil, Sitophilus oryzae was examined under the light and electron microscopes to understand its functional potential in infestation/ovipositional tactics. The microscopic observation revealed that, the length of the rostrum was remarkably longer and thinner for females than in males. This adaptation in females is high...

objective: in the present study, the effects of aqueous saffron extract (crocus sativus l.) on the acquisition and reinstatement of morphine-induced conditioned place preference (cpp) in mice were investigated. materials and methods: subcutaneous administration of morphine (40 mg/kg for four days) produced place preference. intraperitoneal administration of aqueous extract (40 and 80 mg/kg for ...