Lysinibacillus fusiformis: A novel mosquitocidal bacterium isolated from Western Ghats, Kerala, India

Abstract

An extensive field survey was carried out from December 2021 to January 2022 for the collection of soil samples in the Western Ghat region of the Wayanad district of Kerala, India, to isolate potent novel mosquitocidal bacteria which could be used as efficient formulations to control mosquito vectors. Several bacterial colonies were isolated and screened, for mosquitocidal activity. Toxicity assay showed that only one bacterium isolated from forest loamy soil had promising larvicidal activity against Culex quinquefasciatus the lymphatic filariasis vector (LC50: 0.03 mg L-1 & LC90: 0.07 mg L-1) and moderate activity was shown against the dengue vector, Aedes aegypti (LC50: 1.03 mg L-1 & LC90: 1.8 mg L-1). The bacterium was identified as Lysnibacillus fusiformis by a phylogenetic tree constructed using 16S rRNA genome sequencing. This is the first report that L. fusiformis isolated from the forest loamy soil of the Western Ghats, Kerala, which showed proficient mosquitocidal activity against disease-transmitting mosquito vectors.