Effect of Bacillus thuringiensis var. israelensis Sugar Patches on Insecticide Resistant Anopheles gambiae s.l. Adults

BACKGROUND

Large distribution of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) contributed to a significant decrease in malarial mortality. Unfortunately, large insecticide resistance in malaria vectors occurred and is a threat to the future use of these control approaches. The purpose of this study was to explore a new approach for vector control. Patches containing Bacillus thuringiensis var. israelensis (Bti) solubilized Cry toxins mixed with sugar were developed and tested in the laboratory with pyrethroid-resistant Anopheles gambiae s.l. using tunnel tests.

METHODS

Mosquitoes were released at 6:00 p.m. into a large tunnel separated by a bed net, perforated with nine holes, from a smaller chamber with a guinea pig. Nine Bti sugar patches (BSPs) were attached to the bed net between the nine holes. Fourteen hours later (8:00 a.m.), mosquitoes were collected from the tunnel and the guinea pig chamber. Live females were kept in cups and were fed a sugar solution (5%) for 72 h and delayed mortality was followed. The results were reported as passing, blood fed and mortality rates.

RESULTS

Mosquito populations that are resistant to the insecticides in the bed net, exhibited high mortality (60%) in the presence of the BSPs. Untreated bed nets with patches in the tunnel test killed 66-95% of the mosquitoes that landed and untreated bed nets were superior to treated bed nets.

CONCLUSION

BSPs efficiently kill resistant mosquitoes that land on treated and untreated bed nets and thus could ultimately reduce the number of vector-borne malarial mosquitoes.

Insight into Salivary Gland Proteomes of Two Polyphagous Stink Bugs: Nezara viridula L. and Halyomorpha halys Stål

The invasive brown marmorated stink bug (BMSB), Halyomorpha halys Stål, and the southern green stink bugs (SGSBs), Nezara viridula L., are widely distributed in Europe, even if the date of introduction and the diet differ. Saliva of Hemipteran pests plays essential roles in the interaction between insects and their host plants. The salivary proteomes of several aphid species have been studied and found to differ according to the species, while no comparative investigation between phytophagous stink bugs has been performed yet. Here, the salivary proteins from two bugs, BMSB and SGSB, are analyzed using LC-MS/MS. Data are available via ProteomeXchange with identifiers PXD011920 and PXD011976. A total of 238 and 305 proteins are identified in salivary glands of BMSB and SGSB, respectively. In comparison with salivary proteome from other Hemiptera, the most striking feature of the salivary gland proteomes of SGSB and BMSB is the similar pattern of protein functions between both species. Some of the proteins are speculated to play a significant role in plant-insect interactions. The results herein provide a framework for future research to elucidate the molecular basis of differential impact of piercing-sucking insects on host plants.