Evaluation of the potency of some entomopathogenic bacteria isolated from insect cadavers on Anopheles arabiensis Giles (Order: Dipthera; Family: Culicidae) mosquito larvae in Nigeria

Abstract

The laboratory evaluation of larvicidal activities of some bacteria namely; Pseudomonas aeruginosa, Bacillus polymyxa and and Bacillus subtilis was assessed against the second and fourth instar of Anopheles arabiensis collected from South West Nigeria. Concentrations ranging from 1.3 x 10 7 cfu/mL to 6.5 x 10 7 cfu/mL were tested on the larvae for a period of 48 h. The disparity in the activities was monitored with B. subtilis displaying the highest activity in both the second and fourth instar with LC 50 of 0.865 and 2.361 mg/mL respectively. P. aeruginosa showed LC 50 of 1.931 and 4.205 mg/mL while the least activity was recorded in B. polymyxa with LC 50 of 5.776 and 7.403 mg/mL. There were significant differences in the LC 50 value of the bacteria on the tested instars. Values obtained from the fourth instar group were significantly different from those obtained from the second instar group in all the treatments. Finding from this study show that B. subtilis may be a potential biocontrol agent of A. arabiensis, the main malaria vector in Nigeria.

Highly effective bacterial agents against Cimbex quadrimaculatus (Hymenoptera: Cimbicidae): isolation of bacteria and their insecticidal activities

“…This genus is the most studied group of bacteria in insect pathology (Boemare and Tailliez 2010) and is commonly recognized as definitive insect pathogens (Stahly et al 2006;Masetti et al 2008). Among Bacillus species, Bacillus subtilis (CQ3) and Bacillus tequilensis (CQ4) have been isolated from many insect species belonging to a variety of different orders at various times (Omoya and Akinyosoye 2011;Sevim et al 2012a). In one study, Omoya and Akinyosoye (2011) isolated and characterized a Bacillus subtilis strain from cockroaches, and indicated that it had a significant effect on Anopheles arabiensis, the main malaria vector.…”

“…Among Bacillus species, Bacillus subtilis (CQ3) and Bacillus tequilensis (CQ4) have been isolated from many insect species belonging to a variety of different orders at various times (Omoya and Akinyosoye 2011;Sevim et al 2012a). In one study, Omoya and Akinyosoye (2011) isolated and characterized a Bacillus subtilis strain from cockroaches, and indicated that it had a significant effect on Anopheles arabiensis, the main malaria vector. We also found B. subtilis from C. quadrimaculatus to be an effective pathogen, and had 100 % insecticidal activity on this pest.…”

Potential of bacterial derived biopesticides in pest management

“…Lalithambika et al (2014) reported the efficient biocontrol of the Dengue Vector A. aegypti (Diptera: Culicidae) using an exotoxin derived from P. fluorescens. Omoya and Akinyosoye (2011) and Mostakim et al (2012) reported the larvicidal potency of P. aeruginosa strains on the Anopheles arabiensis (Diptera: Culicidae), the main malaria vector in Nigeria and the olive fruit fly Bactrocera oleae larvae (Diptera: Tephritidae) respectively. Silva et al (2014) reported the larvicidal potency of P. aeruginosa LBI 2A1 derived rhamnolipids against A. aegypti larvae.…”

Anopheline Mosquitoes and the Malaria Scourge

“…It was originally isolated from natural Lepidopteran die-offs in Germany and Japan. Activity of Bt against species of mosquitoes were reported [57]. Bt products have been available since the 1950s.…”