Control of Aedes mosquito populations using recombinant microalgae expressing short hairpin RNAs and their effect on plankton

Abstract

New biocontrol strategies are urgently needed to combat vector-borne infectious diseases. This study presents a low-cost method to produce a potential mosquito insecticide that utilizes the microalgae released into suburban water sources to control mosquito populations.Chlorellamicroalgae are ubiquitous in local waters, which were chosen as the host for genetic transfection. This species facilitated the recombinant algae to adapt to the prevailing environmental conditions with rapid growth and high relative abundance. The procedure involved microalgae RNAi-based insecticides developed using short hairpin RNAs targeting theAedes aegyptichitin synthase A (chsa) gene inChlorella. These insecticides effectively silenced thechsagene, inhibitingAedesmetamorphosis in the laboratory and simulated-field trials. This study explored the impact of recombinant microalgae on the phytoplankton and zooplankton in suburban waters. High-throughput sequencing revealed that rapid reproduction of recombinantChlorellaindirectly caused the disappearance of some phytoplankton and reduced the protozoan species. This study demonstrated that a recombinant microalgae-based insecticide could effectively reduce the population ofAedesmosquitoes in the laboratory and simulated field trials. However, the impact of this technology on the environment and ecology requires further investigation.