Entomopathogenic fungus spores in the larval habitat water of Culex quinquefasciatus mosquito in Dhaka city, Bangladesh

Abstract

Density of entomopathogenic fungi spores in the larval habitat water of Culex quinquefasciatus was conducted at the Entomology laboratory and Plant Pathology laboratory, Jagannath University, Dhaka, Bangladesh. The larvae and pupae of different mosquito species were counted; water was preserved for fungal culture. Potato Dextrose Agar (PDA) medium was used for culture and different levels of dilution were performed for culture of fungus spores. These stagnant dirty drain water samples have been containing a few (10) Aedes larvae; coexisting with a huge Culex at the same breeding ground. A total of 4138 mosquito larvae and pupa were recorded in the collected habitat water where 3928 larvae and 200 pupa of Culex were observed with different larval densities among collection points. Out of eighteen (18) fungal isolates under 10 genera (Absidia sp., Aspergillus sp., Cladosporium sp., Curvularia sp., Fusarium sp., Geotrichum sp., Nigrospora sp., Penicillium sp., Rhizopus sp. and Sclerotium sp.) were identified, seven (7) of them have been reported as entomopathogenic by scientists; to date. Eight (8) isolates were belonging to the genus Aspergillus. Relationship of larval density of Culex were very weak to total spores of all fungi (r = -0.154) as well as with the number of individual isolates of fungus spores. Culture of entomopathogenic fungi in laboratory condition, and use of them as a biological control agent for the mosquitoes could not be recommended.