Evaluation of larvicidal potential of certain insect pathogenic fungi extracts against Anopheles stephensi and Culex quinquefasciatus

Prejwltta Maurya,Lalit Mohan,Preeti Sharma,C.N. Srivastava 한국곤충학회 2011 Entomological Research Vol.41 No.6

Fungal metabolites are attracting attention as potential microbial insecticides, and they are anticipated to overcome the problems of pesticide resistance and environmental pollution that are associated with the indiscriminate use of conventional synthetic insecticides. The relative bioefficacies of selected fungal pathogens, Aspergillus flavus, A. niger, A. parasiticus, Fusarium sporotrichoides and Penicillium verrucosum were observed against Anopheles stephensi and Culex quinquefasciatus larvae. A. flavus demonstrated the greatest bioefficacy with 50% lethal concentration (LC50) values of 9.54 and 10.98 ppm against Anopheles stephensi and Culex quinquefasciatus larvae, respectively, after 24-h exposure. The bioefficacy of A. flavus increased in both species with an exposure time of 48 h, with LC50 values of 7.26 and 8.55 ppm, respectively.

Evaluation of the toxicity of different phytoextracts of Ocimum basilicum against Anopheles stephensi and Culex quinquefasciatus

Prejwltta Maurya,Preeti Sharma,Lalit Mohan,Lata Batabyal,C.N. Srivastava 한국응용곤충학회 2009 Journal of Asia-Pacific Entomology Vol.12 No.2

The larvicidal effect of the crude carbon tetrachloride, methanol and petroleum ether leaf extracts of a widely grown medicinal plant, Ocimum basilicum, against Anopheles stephensi and Culex quinquefasciatus was evaluated. Petroleum ether extract was found to be the most effective against the larvae of both mosquitoes, with LC50 values of 8.29, 4.57; 87.68, 47.25 ppm and LC90 values of 10.06, 6.06; 129.32, 65.58 ppm against A. stephensi and C. quinquefasciatus being observed after 24 and 48 h of treatment, respectively. The efficacy of petroleum ether was followed by that of the carbon tetrachloride and methanol extracts, which had LC50 values of 268.61, 143.85; 446.61, 384.84 ppm and LC90 values of 641.23, 507.80; 923.60, 887.00 ppm against A. stephensi after 24 and 48 h, respectively, and LC50 values of 24.14, 17.02; 63.48, 53.77 ppm and LC90 values of 295.38, 204.23; 689.71, 388.87 ppm against C. quinquefasciatus after 24 and 48 h of treatment, respectively. These extracts are highly toxic against mosquito larvae from a range of species; therefore, they may be useful for the management of mosquito larvae to control vector borne diseases. The larvicidal effect of the crude carbon tetrachloride, methanol and petroleum ether leaf extracts of a widely grown medicinal plant, Ocimum basilicum, against Anopheles stephensi and Culex quinquefasciatus was evaluated. Petroleum ether extract was found to be the most effective against the larvae of both mosquitoes, with LC50 values of 8.29, 4.57; 87.68, 47.25 ppm and LC90 values of 10.06, 6.06; 129.32, 65.58 ppm against A. stephensi and C. quinquefasciatus being observed after 24 and 48 h of treatment, respectively. The efficacy of petroleum ether was followed by that of the carbon tetrachloride and methanol extracts, which had LC50 values of 268.61, 143.85; 446.61, 384.84 ppm and LC90 values of 641.23, 507.80; 923.60, 887.00 ppm against A. stephensi after 24 and 48 h, respectively, and LC50 values of 24.14, 17.02; 63.48, 53.77 ppm and LC90 values of 295.38, 204.23; 689.71, 388.87 ppm against C. quinquefasciatus after 24 and 48 h of treatment, respectively. These extracts are highly toxic against mosquito larvae from a range of species; therefore, they may be useful for the management of mosquito larvae to control vector borne diseases.

Larvicidal efficacy of Aloe barbadensis and Cannabis sativa against the malaria vector Anopheles stephensi (Diptera: Culicidae)

Prejwltta MAURYA,Lalit MOHAN,Preeti SHARMA,Lata BATABYAL,C. N. SRIVASTAVA 한국곤충학회 2007 Entomological Research Vol.37 No.3

Anopheles stephensi is the primary vector of malaria, an endemic disease in India. An effort to controlAn. stephensi larvae by leaf extracts of Aloe barbadensis (Liliaceae) and Cannabis sativa (Moraceae) was made under laboratory conditions. A carbon tetrachloride extract of A. barbadensis was the most effective of all the extracts tested for larvicidal activity against the anopheline larvae, with LC50 15.58and 8.04 p.p.m. after 24 and 48 h of exposure, respectively. Thus, the leaf extract of A. barbadensishas active components that could be useful as a larvicide of ecocongenial nature against malaria vectors.

Prospective role of insecticides of fungal origin: Review

Chand Narayan SRIVASTAVA,Prejwltta MAURYA,Preeti SHARMA,Lalit MOHAN 한국곤충학회 2009 Entomological Research Vol.39 No.6

Advances in the application of microbial-based technology in insect pest management assist us to counter problems created by the application of chemical pesticides. These are mainly strong environmental effects, resistance development and high costs. Among the microbial pesticides, fungal pesticides are now preferred as they are target specific, ecofriendly, lacking in toxic residue and are economical. Being numerous with great diversification, entomopathogenic fungi therefore have great potential to control a large variety of insect pests. Fungi are applied directly in form of spores, mycelia or blastospores or by their metabolites (mycotoxins). Both approaches have very promising roles in insect pest management. However, there are three main obstacles in the development of fungal pesticides: (i) scant production of mycotoxins; (ii) carcinogenic mycotoxicosis in non-target organisms; and (iii) slow effectiveness. Therefore, to eliminate these problems, attention has recently been paid to a synergistic approach to combating insecticide resistance. Next to synergism, genetic manipulation is also used to enhance the pathogenicity and virulence of fungal insecticides. However, the key risk associated with the release of recombinant microorganisms into the environment is that the novel organism may have unforeseen undesirable characteristics. Therefore, the introduction of synergists in pest control could have great benefit both economically and ecologically. An ideal synergistic approach is the mixing of more than two accelerating components together, i.e. tripartite or multiple synergism to enhance effectiveness. Thus, synergistic approaches have a bright future and require further research and financial support.

Larvicidal Efficiency of Certain Seed Extracts Against Anopheles Stephensi, with Reference to Azadirachta indica

Lata Batabyal,Preeti Sharma,Lalit Mohan,Prejwltta Maurya,C.N. Srivastava 한국응용곤충학회 2007 Journal of Asia-Pacific Entomology Vol.10 No.3

The toxicity of seed extracts of three Indian medicinal plants, Azadirachta indica, Momordica charantia and Ricinus communis, was evaluated for their larvicidal efficacy against Anopheles stephensi. The methanol extract of A. indica exhibited potent larvicidal activity with LC50 15.25 and 12.70 ppm and LC90 46.79 and 45.56 ppm after 24 and 48 hrs, respectively, followed by methanol extract of R. communis with LC50 54.95 and 23.06 ppm and LC90 251.03 and 144.54 ppm after 24 and 48 hrs of post treatment, respectively. In case of M. charantia, the carbon tetrachloride extract possess potential larvicidal efficacy with LC50 values 87.00 and 57.53 ppm and LC90 301.20 and 262.21 ppm after 24 and 48 hrs of exposure period. The results indicate that A. indica methanol extract was most potential mosquito larvicide and can be use as alternate potential to synthetic insecticides.

Larvicidal Efficiency of Certain Seed Extracts Against Anopheles Stephensi, with Reference to Azadirachta indica

Batabyal, Lata,Sharma, Preeti,Mohan, Lalit,Maurya, Prejwltta,Srivastava, C.N. Korean Society of Applied Entomology 2007 Journal of Asia-Pacific Entomology Vol.10 No.3

The toxicity of seed extracts of three Indian medicinal plants, Azadirachta indica, Momordica charantia and Ricinus communis, was evaluated for their larvicidal efficacy against Anopheles stephensi. The methanol extract of A. indica exhibited potent larvicidal activity with $LC_{50}$ 15.25 and 12.70 ppm and $LC_{90}$ 46.79 and 45.56 ppm after 24 and 48 hrs, respectively, followed by methanol extract of R. communis with $LC_{50}$ 54.95 and 23.06 ppm and $LC_{90}$ 251.03 and 144.54 ppm after 24 and 48 hrs of post treatment, respectively. In case of M. charantia, the carbon tetrachloride extract possess potential larvicidal efficacy with $LC_{50}$ values 87.00 and 57.53 ppm and $LC_{90}$ 301.20 and 262.21 ppm after 24 and 48 hrs of exposure period. The results indicate that A. indica methanol extract was most potential mosquito larvicide and can be use as alternate potential to synthetic insecticides.