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Significant progress has been made in understanding the cues involved in the host and mate seeking behaviors of spotted wing drosophila, Drosophila suzukii (Matsumura). This insect pest has been discovered in many fruit growing regions around the world since 2008. Unlike closely related Drosophila species, D. suzukii attacks fresh fruit and has become a severe pest of soft fruits including strawberry, cherry, blackberry, blueberry, raspberry, and may pose a threat to grapes. Prior to 2008, little was known about the courtship and host-seeking behaviors or chemical ecology of this pest. Since then, researchers have gained a better understanding of D. suzukii attraction to specific odors from fermentation, yeast, fruit, and leaf sources, and the visual cues that elicit long-range attraction. Several compounds have also been identified that elicit aversive behaviors in adult D. suzukii flies. Progress has been made in identifying the constituent compounds from these odor sources that elicit D. suzukii antennal responses in electrophysiological assays. Commercial lures based on food volatiles have been developed to attract D. suzukii using these components and efforts have been made to improve trap designs for monitoring this pest under field conditions. However, current food-based lures and trap technologies are not expected to be specific to D. suzukii and thus capture large numbers of non-target drosophilids. Attractive and aversive compounds are being evaluated for monitoring, mass trapping, and for the development of attract-and-kill and push-pull techniques to manage D. suzukii populations. This review outlines presently available research on the chemical ecology of D. suzukii and discusses areas for future research.

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The use of glyphosate‐based herbicides in agroecosystems has increased over the past few years because of the advent of genetically modified glyphosate‐resistant crops and resistant weeds. This is alarming because of potential damaging effects on non‐target organisms. In sub‐Saharan Africa, for example Ghana, many rural farmers have not received training in the use of glyphosate‐based herbicides, thus tend to apply higher than recommended concentrations on farms. Therefore, this study investigated the effect of glyphosate‐based herbicides on beneficial insects under laboratory conditions, using Apis mellifera L. (Hymenoptera: Apidae, Apini) and Hypotrigona ruspolii (Magretti) (Hymenoptera: Apidae, Meliponini) as models. The bees were put in contact for 24 h with the recommended concentration of Sunphosate 360 SL, a glyphosate‐based herbicide, 2× the recommended concentration, or distilled water as control. The effect of the herbicide on the bees was compared to the effect of a lambda‐cyhalothrin insecticide. Generally, more bees died after contact with plants freshly sprayed with the herbicide than on herbicide‐treated filter paper. In both cases, more bees died after contact with the higher concentration of the herbicide. These findings suggest that beneficial insects, specifically A. mellifera and H. ruspolii, may get killed if they are sprayed upon or come into contact with plants that have been freshly sprayed with (more than) the recommended concentration of glyphosate‐based herbicides. Therefore, it is important to restrict access and use of such herbicides to trained personnel who will comply with spraying guidelines, that is, recommended concentrations and timing of spray. Spraying at a time when insects are flying about may be detrimental to beneficial insects such as pollinator bees, parasitoids, and predators.

The volatile organic compounds (VOCs) of four monofloral and one multifloral of Thai honeys produced by Apis cerana, Apis dorsata and Apis mellifera were analyzed by headspace solid-phase microextraction (HS-SPME) followed by gas chromatography and mass spectrometry (GC-MS). The floral sources were longan, sunflower, coffee, wild flowers (wild) and lychee. Honey originating from longan had more VOCs than all other floral sources. Sunflower honey had the least numbers of VOCs. cis-Linalool oxide, trans-linalool oxide, ho-trienol, and furan-2,5-dicarbaldehyde were present in all the honeys studied, independent of their floral origin. Interestingly, 2-phenylacetaldehyde was detected in all honey sample except longan honey produced by A. cerana. Thirty-two VOCs were identified as possible floral markers. After validating differences in honey volatiles from different floral sources and honeybee species, the results suggest that differences in quality and quantity of honey volatiles are influenced by both floral source and honeybee species. The group of honey volatiles detected from A. cerana was completely different from those of A. mellifera and A. dorsata. VOCs could therefore be applied as chemical markers of honeys and may reflect preferences of shared floral sources amongst different honeybee species.

This study investigated the soil pollution level and evaluated the phytoremediation potential of 25 native plant species on a former gold mine-tailing site in Ghana. Plant shoots and associated soil samples were collected from a tailing deposition site and analyzed for total element concentration of As, Hg, Pb, and Cu. Soil metal(loid) content, bioaccumulation factor (BAF shoots), and hyperaccumulator thresholds were also determined to assess the current soil pollution level and phytoextraction potential. The concentration of As and Hg in the soil was above international risk thresholds, while that of Pb and Cu were below those thresholds. None of the investigated plant species reached absolute hyperaccumulator standard concentrations. Bioavailability of sampled metal(loid)s in the soil was generally low due to high pH, organic matter, and clay content. However, for Cu, relatively high bioaccumulation values (BAF shoots > 1) were found for 12 plant species, indicating the potential for selective heavy-metal extraction via phytoremediation by those plants. The high levels of As at the study site constitute an environmental and health risk but there is the potential for phytoextraction of Cu (e.g., Aspilia africana) and reclamation by afforestation using Leucaena leucocephala and Senna siamea.

Different origins and processing (floral source, honeybee species, and postcollection processing) of Thai honeys result in different antibacterial activities, physico-chemical properties, and aroma. Based on these findings, consumers of honey could select the type of honey based on their needs and preferred aroma.

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