The Influence of Southwestern Virginia Environmental Conditions on the Potential Ability of and to Overwinter in the Region.

Ticks are susceptible to environmental conditions and, to ensure survival during winter conditions, they adopt a wide variety of physiological and behavioral adaptations including utilization of a suitable niche with insulation (e.g., leaf coverage).

Molecular action of pyriproxyfen: Role of the Methoprene-tolerant protein in the pyriproxyfen-induced sterilization of adult female mosquitoes.

Exposure of adult mosquitoes to pyriproxyfen (PPF), an analog of insect juvenile hormone (JH), has shown promise to effectively sterilize female mosquitoes. However, the underlying mechanisms of the PPF-induced decrease in mosquito fecundity are largely unknown. We performed a comprehensive study to dissect the mode of PPF action in Aedes aegypti mosquitoes.

Seasonal Assessment of Supercooling Points for Two Introduced and One Native spp. (Coleoptera: Derodontidae), Predators of Adelgidae.

The hemlock woolly adelgid, Annand, is an invasive insect that threatens hemlock species in eastern North America. Several species from the genus are predators of in its native areas of Asia and the western United States. Two species have been released as biological control agents: Fender, and Montgomery and Shiyake.

Supercooling Points of Murgantia histrionica (Hemiptera: Pentatomidae) and Field Mortality in the Mid-Atlantic United States Following Lethal Low Temperatures.

The harlequin bug, Murgantia histrionica (Hahn), is a serious pest of brassicaceous vegetables in southern North America. While this insect is limited in its northern range of North America, presumably by severe cold winter temperatures, specific information on its cold hardiness remains unknown. We determined the supercooling points (SCPs) for Maryland and Virginia adult populations and found no significant difference among these populations.

Cold Tolerance of Halyomorpha halys (Hemiptera: Pentatomidae) Across Geographic and Temporal Scales.

The brown marmorated stink bug, Halyomorpha halys (Stål), is native to eastern Asia and is presently invading North America. Little is known about the exposure to and effects of winter temperatures in newly invaded regions on H. halys The overwintering habitats that this species utilizes vary greatly in their thermal buffering capacity.

Fitness and physiology of Adelges tsugae (Hemiptera: Adelgidae) in relation to the health of the eastern hemlock.

The hemlock woolly adelgid, Adelges tsugae Annand is an invasive insect that frequently causes hemlock (Tsuga spp.) mortality in the eastern United States. Studies have shown that once healthy hemlocks become infested by the adelgid, nutrients are depleted from the tree, leading to both tree decline and a reduction of the adelgid population.

Physiology of environmental adaptations and resource acquisition in cockroaches.

Cockroaches are a group of insects that evolved early in geological time. Because of their antiquity, they for the most part display generalized behavior and physiology and accordingly have frequently been used as model insects to examine physiological and biochemical mechanisms involved with water balance, nutrition, reproduction, genetics, and insecticide resistance. As a result, a considerable amount of information on these topics is available.

Characterization of physical and chemical defenses in the hemlock woolly adelgid.

The invasive hemlock woolly adelgid (Adelges tsugae Annand, Hemiptera: Sternorrhyncha: Adelgidae) causes significant mortality to eastern and Carolina hemlock (Tsuga canadensis Carrière and T. caroliniana Engelmann, respectively) throughout the eastern United States. Adelges tsugae produces vast quantities of a wax covering that surrounds most of the instars as well as the adult and eggs.

Potential feeding deterrents found in hemlock woolly adelgid, Adelges tsugae.

The nonnative hemlock woolly adelgid (Adelges tsugae Annand, Hemiptera: Sternorrhyncha: Adelgidae) has been a significant mortality agent of eastern hemlock (Tsuga canadensis Carriere) throughout a large portion of its geographic range. During a study investigating adelgid vigor in relation to host health, it was noted that adelgid extracts ranged from a yellow to a deep red color. Analysis by GC-MS identified the presence of the anthraquinone, chrysophanol and its anthrone precursor, chrysarobin in the extract.

Evaluation of ELISA for imidacloprid detection in eastern hemlock (Tsuga canadensis) wood and needle tissues.

Background: Imidacloprid is the primary insecticide used against the exotic invasive insect hemlock woolly adelgid, Adelges tsugae Annand, a pest of eastern hemlock [Tsuga canadensis (L.) Carrière] trees in the eastern United States. A competitive enzyme-linked immunosorbent assay (ELISA) was evaluated for quantification of imidacloprid in eastern hemlock wood and needle tissues.

The fate of 14C-diazinon in compost, compost-amended soil, and uptake by earthworms.

A process for disposing of pesticide rinsates using sorption onto organic matter followed by composting is being evaluated. As a part of this evaluation process, we have studied the bioavailability of composted delta-2-14C-diazinon and its degradation products to earthworms (Eisenia foetida Savigny) in 30 and 60 d compost amended soil. After 60 d of composting there was considerable degradation of diazinon (95%) and a corresponding increase in the primary hydrolysis product, 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMHP) as determined by high performance thin layer chromatography (HPTLC).

The structural basis for water exchange between the female cockroach (Blattella germanica) and her ootheca.

Female German cockroaches usually carry their oothecae until they hatch. The success of embryogenesis may be dependent on the water-balance relationship between females and their developing oothecae. Oothecae detached from females early in embryogenesis often fail to develop, especially in low-humidity environments.