JOURNAL OF INTERNATIONAL ACADEMIC RESEARCH FOR MULTIDISCIPLINARY Impact Factor 3.114, ISSN: , Volume 4, Issue 10, November 2016

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1 EVALUATION OF LARVICIDAL ACTIVITY OF TRIDAX PROCUMBENS LEAVES AGAINST FILARIAL VECTOR MOSQUITO, CULEX QUINQUEFASCIATUS Dr. RUCHI DESAI* *Teaching Assistant, Dept. of Biotechnology, Veer Narmad South Gujarat University, Surat, Gujarat, India Abstract Mosquitoes constitute a major public health menace, they not only cause nuisance by their bites but also transmit deadly diseases like malaria, filariasis, yellow fever, dengue and Japanese encephalitis, thus contributing significantly to poverty and social debility in tropical countries. The mosquito Culex quinquefasciatus acts as a vector for Wuchereria bancrofti responsible for filariasis in India. However, control of such diseases are becoming increasingly difficult because the over production of detoxifying mechanisms of chemical insecticides has been reported for Culex species. The selective pressure of conventional insecticides is enhancing resistance of mosquito populations at an alarming rate, increasing the demand for new products that are eco-friendly, target-specific and easily degradable. Plants are considered as a rich source of bioactive chemicals and they may be an alternative source of mosquito control agents. For that reason larvicidal activity of methanolic extract of plant leaves- Tridax procumbens (Asteraceae) against mosquito vector Culex quinquefasciatus (culicidae) was examined. Various doses ranging from concentration 50 ppm to 500 ppm were tested against 4 th instar larvae of mosquito Culex quinquefasciatus for its larvicidal and 24 hrs mortality. The extract formulation produced dose dependent activity, demonstrated larvicidal effect and produced remarkable mortality. At 500 ppm around 95% mortality was detected with Tridax leaves. Moreover the pupa formed is deformed and mostly does not survive to adulthood of the plants. The results obtained suggested the presence of potential larvicidal effect of T.procumbens on Culex quinquefasciatus. Introduction: Pest management is an important and vital component in present world. A crucial component of this management is the use of chemicals to control insect pest, which not only attack plants and plant products at various stages of production, but also destroy structures and transmit human and livestock diseases. There are approximately three million insect species in the world, amounting to 80% of all species in the animal kingdom. Of these around 10,000 have been recognized as harmful. Human loss as a result of insect borne diseases such as malaria, filariasis, dengue, trypanosomiasis, etc., are enormous. 40

2 Insects transmitted diseases remain a major source of illness and death worldwide. Mosquito alone transmit diseases to more than 700 million people annually. Mosquitoes comprises the most important single group of insects in terms of public health, which transmits a number of diseases, such as malaria, filariasis, dengue, Japanese encephalitis, etc. causing millions of deaths every year. Repeated use of synthetic insecticides for mosquito control has disrupted natural biological control systems and has led to resurgences in mosquito populations. It has also resulted in the development of resistance, undesirable effects on non-target organisms and fostered environmental and human health concern. Thus, control of harmful insects is a must for mankind. Though various new strategies for plant protection and insect control are emerging, insecticides continue to play a dominant role, and it appears unlikely that insecticides will ever be bypassed. However there is enormous scope for discovery of safer, more potent and environmentally non-polluting insecticides. This initiated a search for alternative control measures. Plants are a rich source of bioactive chemicals and they may be an alternative source of mosquito control agents. Natural products of plant origin with insecticidal properties have been tried in the recent past for control of a variety of insect pests and vectors. The mosquito, Culex quinquefasciatus Say, is one of the potential vectors of Wuchereria bancrofti, the causative agent of human lymphatic filariasis (HFL) all over the world, including India. So, in order to prevent mosquito-borne diseases and improve public health, it is necessary to control them by safe methods such as use of plants and their effective products. Herbal products with proven potential as insecticide or repellent can play an important role in the interruption of the transmission of mosquito-borne diseases at individual as well as at the community level. Tridax procumbens (L.): T. procumbens, is a common annual weed occurring throughout the tropical and subtropical belt of the world. It belongs to family Asteraceae. It is best known as a widespread weed and pest plant. The plant has therapeutic values, it has been claimed that it has hepatoprotective, antiinflammatory and immunomodulatory activities. Tridax procumbens showed growth inhibitory and juvenile hormone mimicing activity to the treated larvae of C. quinquefasciatus. The extracts of Tridax procumbens have been reported to have various pharmacological effects, antimicrobial activity against both gram-positive and gram-negative bacteria, and stimulate wound healing. Flavones, glycoside, polysaccharide, monosaccharides and asteraceae have been isolated from the leaves of the plant. Leaf juice has insecticidal and pesticidal effect, also used to check hemorrhages. 41

3 MATERIALS AND METHODS: Test organism Culex quinquefasciatus: For the present study, the mosquito species was cultured in the laboratory. A single gravid female purpose was maintained from the second generation onwards. Chick blood meal was given to the females so as to produce egg-rafts. Larvae, pupae and adult were taken care of separately. For the present study Tridax leaves were collected from the campus of V.N.S.G. University, Surat. Leaves were shade dried and powdered. This powder was subjected to Soxhlet extraction using Methanol as the solvent, for 4-5 hrs for 5 days. Then the solvent was evaporated and the crude extract was stored in the refrigerator until assayed. These dried extracts were later redissolved in Methanol to prepare stock solution at the time of preparation of test doses. RESULTS : Toxic effects of the extracts were studied by counting the larval mortality after 24hrs. Mortality was calculated using Abbott s formula. Various test doses ranging from 50ppm to 500ppm of T. procumbens were experimented on fourth instar larvae of Cx. quinquefasciatus. The results revealed that the extract caused reduction in adult emergence from 56.11% at 50ppm to 4.17 th% only at 500ppm. As concentration increased more number of larvae were affected than pupae of adults % total mortality was found at 500ppm where there was no pupal or adult mortality was observed. Thus the overall controlling effect of the extract was mainly due to larval mortality only. It was observed that at higher concentration the time required for larvalpupal development decreases. Growth indices showed significant less value than the solvent and the untreated controls. Thus e high total mortality values and low growth indices proves the effectiveness of the plant extract. ABBOTT'S FORMULA: Corrected % Mortality = (% alive control - % alive treated) x 100% (% alive control) 42

4 120 Mortality effect of Tridax procumbens on Culex quinquefasciatus mosquito Mortality (%) Larva Pupa Adult Concentration (ppm) 500 CONCLUSION:- From the results we can conclude that the present plants has got enough potential to fight against the larvae of Culex quinquefasciatus mosquito and can be helpful in reducing their population. This will be a safer and eco-friendly way of controlling the mosquito menace. Several investigators have evaluated toxic effects of plant-derived insecticides on different stages in the life cycle of mosquitoes. In current study, methanolic extract of Tridax procumbens was found to be the most toxic with lowest LC 50 value of ppm. The extract was also effective on pupal and adult stages. 100% mortality was found at 500ppm concentration. Tridax belongs to family Asteraceae (Compositae) which include several important plants that are found effective against many mosquito species. Tagetes sp are the most effective plants belonging to Asteraceae family. The results of this study will contribute to a great reduction in the application of synthetic insecticides, which in turn increase the opportunity for natural control of various medically important pests by botanical pesticides. Since these are often active against a limited number of species including specific target insects, less expensive, easily biodegradable to non-toxic products, and potentially suitable for use in mosquito control programme. 43

5 REFERENCES:- 1. Abbott WS A method for computing the effectiveness of an insecticide. J Econ Entomol 18; Bako, S.P., Bakful, M.J., John, I. and Bala, E.I Ethanomedicinal and 3. Mallick, R. N., Das, P.C. and Chatterjee, S. M Curr. Sci., 54(21) : Phytochemical Profile of Some Savanna Plant Species in Nigeria. International Journal of Botany. 1(2) : Pushpalatha, E. and Muthukrishnan, J. (1995). Larvicidal activity of a few plant extracts against Culex quinquefasciatus and Anopheles stephensi. Indian J. Malariol., 31: Salahdeen, H.M., Yemitan, O.K. and Alada, A.R.A Effect of Aqueous Leaf Extract of Tridax procumbens on Blood Pressure and Heart rate in Rats. African Journal of Biomedical Research, Vol -7 : Saxena R.C. and Srivastava, R.P.(1989). A Text book of Insect Toxicology, Himanshu publications, Udaipur. 8. Sharma, M. C. and Saxena, R. C. 1994a. Phytotoxicological evaluation of Tagetes erectes on aquatic stages of Anopheles stephensi. Indian J. Malariol., 31(1) : Taddel, A. and Rosas Romero, A.J. 2000: Bioactivity studies of extracts from Tridax procumbens. Phytomedicine, Jun 7 (3) : Tyagi, B.K. (1994). Alternative control strategies for mosquito vectors of human diseases in India. In : Perspectives in Entomology Research. Agrawal, O.P. [ed]. Scientific Publishers, Jodhpur, pp: Udopa, S.L., Udopa, A.L. and Lalkarni, D.R. 1991: Influence of Tridax procumbens on lysl oxidase activity and wound healing. Planta Med Aug 57(4) : World Health Organization (1981) Instructions for determining the susceptibility or resistance of mosquito larvae to insect development inhibitor. WHO/Vector Biology and Control, Yadawa, R.N. and Saurabh, K A new flavone glycoside: 5,7,4 Trihydraxy 6, 3 dimethasey Falavone 5-0 alpha L- rhamnopyramoside from the leaves of Tridax procumbens Liun. J. Asian Nat. Prod. Res. 1:2, Young, S. J., Bong, R. B., Young, C. Y., Moo, K.K. and Hoi, S. L Larvicidal activity of Leguminous seeds and grains against Aedes aegypti and Culex pipiens Pallens. Journal of American Mosquito Control Association. 18(3) :