Laboratory evaluation of entomopathogenic fungus Metarhizium anisopliae for the control of Anopheles gambiae s. L. Larvae in Bauchi Nigeria
Auwal Al-Hassan Barde, Abba Umar, Musa Mustapha Dogara
The entomopathogenic fungus, Metarhizium anisopliae was cultured and isolated from soil samples which were obtained from the agricultural fields within Yelwa Campus of Abubakar Tafawa Balewa University Bauchi Nigeria. This fungus was used as biocontrol agent against the 4th instar larvae of Anopheles gambiae s. L. under ambient laboratory conditions. Five concentrations ( 1 x 105, 1 x 106, 1 x 107, 1 x 108 and 1 x 109 conidia/ml of the fungal isolate were prepared by adding the sterile 0.02% tween 80 in distilled water. Haemocytometer was used for counting the conidia. The results indicated an increase in the mean larval mortality from 4 to 96% as the concentration of the fungal isolate was increased from 1 x 105 to 1 x 109 Conidia/ml as the time of exposure was increased from 24 to 96 hours. This was reflected by the decrease in the values of LC50 from 5.75 x 108 to 7.10 x 105 while the values of LC90 decreased from 5.20 x 1011 to 9.77 x 107. This performance of the M. anisopliae in the biocontrol of mosquito larvae further encourages the use of the entomopathogenic fungi in an effort to reduce the spread of some vector-borne diseases in some parts of sub-Saharan regions of Africa.