Comparison of the Effect of Insecticides on Bumble Bees (Bombus impatiens) and Mosquitoes (Aedes aegypti and Culex quinquefasciatus) by Standard Mosquito Research Methods.

Mosquito control districts in the United States are limited to two main classes of adulticides, pyrethroids and organophosphates, to control mosquitoes. Two adulticides used to control domestic mosquitoes are Fyfanon EW (malathion, organophosphate) and DeltaGard (deltamethrin, pyrethroid). While the effect of these pesticides on European honeybees (Apis mellifera L., Hymenoptera: Apidae) has been investigated, effects on native pollinators need additional research. The purpose of this study was to investigate the acute nontarget effects of these pesticides on Bombus impatiens Cresson (Hymenoptera: Apidae), a native North American bumble bee species, and compare these effects to wild and laboratory strains of mosquitoes (Aedes aegypti (L.) and Culex quinquefasciatus Say, Diptera: Culicidae) through field and laboratory assays. Bombus impatiens was found to be resistant to Fyfanon EW (x̅ = 6.7% mortality at 50-µg malathion per bottle) at levels that caused significant mortality to study mosquitoes (86.2 ≥ x̅ ≥ 100% mortality) in laboratory bottle bioassays. Comparatively, B. impatiens demonstrated greater mortality to DeltaGard (93.3%) at 2.5-µg deltamethrin/bottle than any mosquito colony assayed (14.1 ≥ x̅ ≥ 87.0% mortality). Only DeltaGard was tested in field applications. In the field, we observed acute effects of DeltaGard on mosquitoes and B. impatiens at 25- and 75-m distance from a truck-mounted ultra-low volume fogger, although treatment effects were not significant for B. impatiens. Additional wild-caught nontarget mortality to DeltaGard field trials was also evaluated. This study indicated that common mosquito control adulticides do cause nontarget mortality to B. impatiens but that impacts are variable depending on pesticide and further studies are needed.

Mitochondrial nucleotide variability in invasive populations of the root weevil Diaprepes abbreviatus (Coleoptera: Curculionidae) of Florida and preliminary assessment of Diaprepes sp. from Dominica.

Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae) is a root weevil introduced into the United States from the Caribbean in 1964. It is associated with >300 plants, including citrus, sugarcane, and potatoes. D. abbreviatus is widespread in Florida, and it has recently been detected in limited areas of California and Texas. The purpose of this research is to evaluate the utility of 16S ribosomal (16S rRNA) and cytochrome oxidase I (COI) mitochondrial markers for the delineation of genetic populations of D. abbreviatus in Florida and for the characterization of patterns of dispersion among these populations. We also assessed these markers as genetic tools for the clarification of taxonomic uncertainties in specimens from Dominica (Lesser Antilles). We analyzed 111 weevils from six Florida populations and six specimens from Dominica. In Florida, we found three haplotypes with only one haplotype in each population. Florida haplotypes differed by one to three nucleotide substitutions, possibly the result of a recent divergence from one source population or three different introductions from closely related populations from the Caribbean. In contrast, specimens from Dominica showed a high genetic variability with three 16S haplotypes and six unique COI haplotypes, delineating two mitochondrial clades. We show that these mitochondrial markers are useful for phylogeographic studies of D. abbreviatus.

Biological stress response terminology: Integrating the concepts of adaptive response and preconditioning stress within a hormetic dose-response framework.

Many biological subdisciplines that regularly assess dose-response relationships have identified an evolutionarily conserved process in which a low dose of a stressful stimulus activates an adaptive response that increases the resistance of the cell or organism to a moderate to severe level of stress. Due to a lack of frequent interaction among scientists in these many areas, there has emerged a broad range of terms that describe such dose-response relationships. This situation has become problematic because the different terms describe a family of similar biological responses (e.g., adaptive response, preconditioning, hormesis), adversely affecting interdisciplinary communication, and possibly even obscuring generalizable features and central biological concepts. With support from scientists in a broad range of disciplines, this article offers a set of recommendations we believe can achieve greater conceptual harmony in dose-response terminology, as well as better understanding and communication across the broad spectrum of biological disciplines.

Bullous phytophotodermatitis associated with high natural concentrations of furanocoumarins in limes.

BACKGROUND: Phytophotodermatitis is a phototoxic reaction, occurring in skin exposed to sunlight after contact with plants containing furanocoumarins. Typical reactions are mild, showing erythema with post-inflammatory hyperpigmentation. A 6-year-old boy presented with marked, symmetric, painful erythema and edema of both hands that rapidly developed into dramatic bullae covering the entire dorsum of the hands. The history revealed that the hands had been bathed in lime juice for a prolonged period in the preparation of limeade. OBJECTIVE: This report documents an unusual bullous presentation of phytophotodermatitis resulting from contact with furanocoumarins in local limes. This study was conducted to identify and measure the inciting substances from the rind and pulp of the limes. METHODS: Psoralen, xanthotoxin, bergapten, and isopimpinellin content were measured by gas chromatography and high-pressure liquid chromatography RESULTS: The rind contained 6- to 182-fold concentrations of all furanocoumarins measured when compared with pulp. Bergapten was the most abundant substance in the rind. CONCLUSION: Hydration of the skin during the preparation of limeade combined with increased levels of bergapten in local limes to produce a dramatic bullous reaction. We encourage clinicians to consider the possibility of phytophotodermatitis in severe bullous skin reactions.