The sorghum ( Sorghum bicolor [L.]) agroecosystem of North America provided an opportunity to evaluate response invading insect herbivore, Melanaphis sorghi (Theobald) (sorghum aphid) (previously published as sacchari Zehntner) (Hemiptera: Aphididae) onto a widely planted crop that experiences range agro-landscape and weather conditions. Initial risk assessments after M. 's invasion in the mid-...

Spatial distribution or how abundances vary through space is an important trait of insect populations. Knowledge of the spatial distribution provides a basis for understanding various aspects of population biology including resource exploitation, intraspecific competition or the dynamics of predators and parasitoids. For insect pests, information on the spatial structure of populations may help...

Symbiotic relationships between animals and microorganisms are common in nature, yet the factors controlling the abundance and distributions of symbionts are mostly unknown. Aphids have an obligate association with the bacterium Buchnera aphidicola (the primary symbiont) that has been shown to contribute directly to aphid fitness. In addition, aphids sometimes harbor other vertically transmitte...

In a natural community of 49 species (12 species of aphids and 37 species of their parasitoids), body lengths of 2,151 parasitoid individuals were, to an excellent approximation, related to the body lengths of their individual aphid hosts by a power law with an exponent close to 3/4. Two alternative models predict this exponent. One is based on surface area to volume relationships. The other is...

Based on the importance of using low-risk compounds to protect beneficial agents, present study evaluated acute toxicity lethal and sublethal concentrations insecticides thiacloprid, pyriproxyfen, chlorantraniliprole adults Aphelinus mali (Haldeman), main parasitoid woolly apple aphid, Eriosoma lanigerum (Hausmann). Similarly, acetamiprid, buprofezin, cyantraniliprole were Acerophagus flavidulu...

BACKGROUND Diapause, a condition of developmental arrest and metabolic depression exhibited by a wide range of animals is accompanied by complex physiological and biochemical changes that generally enhance environmental stress tolerance and synchronize reproduction. Even though some aspects of diapause have been well characterized, very little is known about the full range of molecular and bioc...