DEET is the most widely used insect repellent worldwide. In Drosophila olfactory receptor neurons (ORNs), DEET is detected through a mechanism employing the olfactory receptor, OR83b. However, it is controversial as to whether ORNs respond directly to DEET or whether DEET blocks the response to attractive odors. Here, we showed that DEET suppressed feeding behavior in Drosophila, and this effec...

The enantiomerically enriched γ- and δ-decalactones (4a and 4b) were prepared from corresponding racemic primary-secondary 1,4- and 1,5-diols (1a and 1b), as products of enzymatic oxidation catalyzed by different alcohol dehydrogenases. The results of biotransformations indicated that the oxidation processes catalyzed by alcohol dehydrogenase (HLADH), both isolated from horse liver and recombin...

Glucose is a universal phagostimulant in many animal species, including the cockroach Blattella germanica. However, some natural populations of B. germanica have been found that are behaviorally deterred from eating glucose. In dose-response studies, glucose was a powerful phagostimulant for wild-type cockroaches, but it strongly deterred feeding in a glucose-averse strain. Both strains, howeve...

A secondary metabolite from sponges of the genus Agelas, 4,5-dibromopyrrole-2-carboxylic acid, which is well known as feeding deterrent, was investigated for effects on the cellular calcium homeostasis in PC12 cells. 4,5-Dibromopyrrole-2-carboxylic acid did not change intracellular calcium levels if applied alone without cell depolarization. During depolarization of the cellular membrane using ...

Antifeedant and toxic effects of leaf extracts of Syzygium cumini L., Ocimum basilicum L., Luffa aegyptica Mill., Eichhornia crassipes Mart., Tamarindus indica L., Terminalia catappa L., Limonia acidissima L., Murraya koenigii L., Breynia retusa (Dennst.)., Jatropha curcas L., Tectona grandis L., Momordica charantia L., Mangifera indica L., Ricinus communis L., and the seed extract of Madhuca i...

Recent studies have show that small marine herbivores with limited mobility (mesograzers) often feed on macroalgae chemically defended against fishes or sea-urchins. In order to verify the involved mechanisms of chemotaxis or chemical defense into this process in Brazilian littoral, two species of brown alga Dictyota menstrualis and Dictyota mertensii were studied against the limited mobility h...

Plant derivatives possessing insect repellent and antifeedant properties could offer an alternative approach for managing crop pests and dealing with insect-transmitted diseases. This chapter summarizes results from studies on insecticidal effects of Melia azedarach extracts from Central Argentina. Extracts from different plant structures (green/ripe fruits, green/senescent leaves) and a variet...

In Venezuela, lethal control of wintering Dickcissels (Spiza americana) is considered a threat to the species survival. To help farmers protect their rice and sorghum crops from depredations by Dickcissels and to minimize the killing of large numbers of these birds, alternative non-lethal crop protectionmeasures are needed. To that end, the responses of captive Dickcissels to three bird-repelle...

10 Experimental huts are part of the WHO process for testing and evaluation of Insecticide Treated Nets 11 (ITN) in semi-field conditions. Experimental Hut Trials (EHTs) mostly focus on two main indicators (i.e. 12 mortality and blood feeding reduction) that serve as efficacy criteria to obtain WHO interim 13 recommendation. However, several other outputs that rely on counts of vectors collecte...

In this study, we show that female African malaria mosquitoes Anopheles gambiae starved for 3-5 h start to engorge on sucrose at concentrations between 50 and 75 mmol l(-1). Half of the feeding response (ED50) is reached at 111 mmol l(-1) and the maximum response (0.4 mg) occurs at 250 mmol l(-1). Two receptor cells in a trichoid sensillum of the labellum, called the 'sucrose' and 'water' neuro...