Strategic, sustainable, and ecofriendly alternatives to chemical pesticides are needed to effectively control mosquitoes and reduce the incidence of their vectored diseases. We evaluated several Brassicaceae (mustard family) seed meals as sources of plant derived isothiocyanates produced from the enzymatic hydrolysis of biologically inactive glucosinolates for the control of Aedes aegypti (L., 1762).
View Article and Find Full Text PDFA general method to spin-label a fatty acid was demonstrated as well as an assay of the effectiveness of methyl 10-undecenoate and the spin-labeled version, against the larvae of Aedes aegypti. The LCs were 66 and 58 μL/120 mL (55 and 48 ppm) respectively, and the LCs were 108 and 90 μL/120 mL (113 and 90) ppm. This shows that the spin-label has very little effect on the larvicidal activity of the compound.
View Article and Find Full Text PDFThe repellency and toxicity of a CO-derived cedarwood oil (CWO) was evaluated against actively questing unfed nymphs of four species of hard ticks: Amblyomma americanum (L.), Dermacentor variabilis (Say), Ixodes scapularis Say, and Rhipicephalus sanguineus (Latreille). Using a vertical climb bioassay for repellency, nymphs of these species avoided a CWO-treated filter paper in proportional responses to treatment concentrations.
View Article and Find Full Text PDFFungal entomopathogens are potential tools for the control of mosquito vectors that transmit infectious agents that cause disease in humans and animals. During the infection process, effective recognition of the invading fungi by the mosquito, is a crucial step in mounting an appropriate anti-fungal response. In this study, we investigated the role of peptidoglycan recognition receptors (PGRPs) in host resistance to fungal entomopathogens at the early stages of infection.
View Article and Find Full Text PDFBackground: Some plant essential oils have insecticidal properties against mosquitoes and can be harnessed as ecofriendly tools for mosquito control. We conducted bioassays to determine the toxicity of Italian honeysuckle (Lonicera caprifolium) essential oil and its fractions against larvae of the yellow fever mosquito, Aedes aegypti.
Results: Sixteen constituents were identified in honeysuckle essential oil compared to 15, 15, 15, and 11 constituents in fractions A, B, C, and E, respectively.
We examined the chemical composition of garlic and asafoetida essential oils and their individual and combined toxicity against larvae of Culex pipiens Linnaeus and Culex restuans Theobald (Diptera: Culicidae). The effect of the two essential oils on egg hatch was also examined. Ten and 12 compounds, respectively, were identified in garlic and asafoetida essential oils.
View Article and Find Full Text PDFWe examined the growth characteristics of Tolypocladium cylindrosporum IBT 41712 and its potential to infect eggs of Aedes aegypti and Ae. albopictus at a low temperature (15°C). When grown on Sabouraud dextrose agar supplemented with yeast extract, the IBT 41712 formed white colonies turning to a slightly darker, off-white color when mature.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
September 2016
Strain NRRL B-41902T and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, Gram-stain-negative rods that formed cocci in late stationary phase. 16S rRNA gene sequence analysis showed that strain NRRL B-41902T was most closely related to species within the genera Acinetobacter, and that a grouping of it and the three other closely related strains was most closely related to the type strain of Acinetobacter pittii, which was also confirmed through a phylogenomic analysis.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
September 2016
A bacterial strain, designated WDS2C18T, was isolated from a marine solar saltern from the coast of Weihai, Shandong Province, China. Cells of strain WDS2C18T were long rod-shaped, red, and approximately 6.0-12.
View Article and Find Full Text PDFIsolate A396, a bacterium isolated from a Japanese soil sample demonstrated strong insecticidal and miticidal activities in laboratory bioassays. The isolate was characterized through biochemical methods, fatty acid methyl ester (FAME) analysis, sequencing of 16S rRNA, multilocus sequence typing and analysis, and DNA-DNA hybridization. FAME analysis matched A396 to Burkholderia cenocepacia, but this result was not confirmed by 16S rRNA or DNA-DNA hybridization.
View Article and Find Full Text PDFTechnical improvements in the production and formulation of microbial agents will increase the potential for development of biological pesticides that are able to compete with chemical insecticides in the marketplace. Here we report the efficacy of a simple granule formulation containing microsclerotia of Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) for control of unfed and fed nymphs of Ixodes scpaularis Say (Acari: Ixoididae). Microsclerotial granules of M.
View Article and Find Full Text PDFNootkatone is a component of grapefruit oil that is toxic to the disease-vectoring tick, Ixodes scapularis Say, but unfortunately causes phytotoxicity to treated plants and has a short residual activity due to volatility. We prepared a lignin-encapsulated nootkatone formulation to compare with a previously used emulsifiable formulation for volatility, plant phytotoxicity, and toxicity to unfed nymphs of I. scapularis.
View Article and Find Full Text PDFToxicity of nootkatone was determined in laboratory assays against unfed nymphs of Amblyomma americanum L., Dermacentor variabilis (Say), Ixodes scapularis Say, and Rhipicephalus sanguineus Latreille. We determined the 50% lethal concentration (LC50) and 90% lethal concentration (LC90) of nootkatone by recording tick mortality 24 h after exposure in treated glass vials.
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