Fungus may provide alternative for mosquito control.

Verma, P, and S Prakash. 2010. Efficacy of Chrysosporium tropicum metabolite against mixed population of adult mosquito (Culex quinquefasciatus, Anopheles stephensii and Aedes aegypti) after purification with flash chromatography. Parasitology Research http://dx.doi.org/10.1007/s00436-010-1854-6.

Spraying adult mosquitoes with a chemical made by a fungus provides an innovative way to control some of the most pesky species of mosquitoes, researchers in India report. 

This research is the first to show that Chrysosporium tropicum products may provide effective, biological based insect control for adult mosquitos. The ability to effectively control mosquito populations is of paramount importance in many tropical regions to prevent the spread of infectious diseases – such as malaria – that remain a primary cause of death and illness.

This particular fungus' metabolite could be a promising alternative to some of the synthetic pesticides used to control mosquito populations. Conventional insecticides can pollute the environment and cause health concerns in wildlife and people. They also become ineffective when the insects become resistant to them. Some of these include permethrins and DDT, which is still produced and used in some parts of the world.

Investigators isolated an extract from the fungus Chrysosporium tropicum and tested different concentrations in methanol-based solutions. They found that populations of the mosquito species Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti were effectively controlled when treated with the mixture.

The best results were achieved when nine parts of the fungal metabolites were mixed with one part of the methanol solution. The 9:1 ratio killed 70.58 percent of the mosquitoes after eight hours of exposure.

The three species of mosquitos are of particular concern to public health as they are known to transmit malaria, viral infections and other infectious diseases. Alternative methods of insecticide provide communities with options beyond conventional pesticides for controlling this important disease vector.

Several types of fungal agents are already being used for insect control. Using them for mosquito control is relatively environmentally benign compared to synthetic insectides. While further research is required to determine the best use of Chrysosporium tropicum as an insecticide, this investigation adds to a growing body of research that demonstrates there are effective alternatives for some types of synthetic pesticides.