Abstract
Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya fever, filariasis, encephalitis, west nile virus infection, etc. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances leads to an adverse effects on environment and non target organisms. In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal and ovicidal potential of the crude aqueous and methanol solvent extracts of leaves and seeds of the medicinal plant Pongamia pinnata against the mosquito vectors Culex quiquafaciatus, Anopheles stephensi and Aedes aegypti (Diptera: culicidae).Larvicidal activity of Pongamia pinnata leaf aqueous extract (PPLAE), leaf methanol extract (PPLME); seed aqueous (PPSAE) and seeds methanol extracts(PPSME) was studied in the range of 50-400ppm against fourth instar larvae of Culux quinquefasciatus , An. stephensi and Ae. aegypti in the laboratory. Larvae were exposed to varying concentrations of crude extracts (PPLAE, PPLME, PPSAE and PPSME). Considerable mortality was evident after the treatment of P. pinnata for all three important vector mosquitoes. The ovicidal activity was determined against Cu quinquefaciatus, Ae. aegypti and An. stephensi to various concentrations of leaf and seed methanol extracts (PPLME and PPSME) ranging from 100 to 900 ppm under laboratory conditions. Mean percent hatchability of the eggs were observed after 48h post treatment.All leaf (PPLAE, PPLME) and seed extracts (PPSAE, PPSME) showed moderate larvicidal and ovicidal effects; however, methanol extracts of leaf (PPSME) of P. pinnata against the larvae of Culux quinquefasciatus , Ae. aegypti and An. stephensi LC50 and LC90values of 153.09, 288.24 ppm; 140.656, 277.74 ppm; and 106.27, 231.99 ppm, respectively. P. Pinnate methanol extract of seed (PPSME) LC50 and LC90values of 140.656, 277.74 ppm; 123.572, 228.236ppm and 100.272-231.996 ppm, respectively against the three vector mosquito larvae ovicidal efficacy of P. Pinnata the percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. The methanol leaf extract of P. pinnata against An. stephensi Ae. aegypti and,Culux quinquefasciatus exerted 100% mortality (zero hatchability) at 500, 600 and 700 ppm, respectively, With PPSME 100% mortality at 600, 700 and 700 ppm, respectively. Control eggs showed above 98-100% hatchability. Among the extracts tested, the highest ovicidal activity was observed in the PPLME. Compared to leaf extracts (PPLME) seed extracts (PPSME) have low potency against the three vector mosquitoes.Our data suggest that the crude leaf and seed aqueous (PPLAE, PPSAE) and methanol solvent extracts (PPLME, PPSME)of P. pinnata have the potential to be used as an eco-friendly approach for the control of mosquitoes.

15030212 Larval and Ovicidal effects of Pongamia pinnata pdf

Abstract
The present study has been conducted to understand the protective role of vitamin C on malathion toxicity in the gill for a period of 50 days. Five groups of 10 fish each were exposed separately to malathion (0.71ppm) solution prepared in tap water. Each group was exposed for 6, 12, 25, 35 and 50 days to one of the following treatments:Group I: Control group, fish were reared in tap water and fed on a commercial diet (32% protein).Group II: Control group, fish were reared in tap water and fed on a commercial diet (32% protein) supplemented with 500 mg vitamin C/kg diet.Group III: Fish were exposed to 1/10 LC50(0.71mg/l) of malathion and fed on a commercial diet (32% protein). Group IV: Fish were exposed to 0.71mg/l of malathion and fed on a commercial diet (32% protein) supplemented with 500 mg vitamin C/kg diet.In Group III, the gills showed extensive damages in their lamellar configuration even though the gill continue to regenerate repeatedly after every wear and tear, especially during the initial stages. The gill showed fusion of SL with the neighbouring gill filament and form undifferentiated mass of cells. The present study indicated that malathion at sub-lethal levels under laboratory conditions had the capacity to alter the normal physiological functions gills of catfish, C. batrachus.

15030211 Studies on Malathion Toxicity in the Gill of the Catfish Clarias batrachus (Linn.) pdf

Abstract
Coir pith was considered as an agro waste in the yester years. Coir pith as an organic waste is suitable for vermicomposting, potting medium in horticulture industry and as a suitable agricultural amendment. Though coir pith is suitable for many techniques, there are also some constraints present in using the raw coir pith, such as high EC, high cation exchange capacity, low pH, high amount of soluble salts like potassium, calcium, magnesium, sodium and chloride. In order to overcome these constraints the present study was undertaken and particular issues were studied. Thus the process of pre-processing of coir pith i.e. washing the coir pith repeatedly for several times (7 times) was found effective in overcoming the constraints in the usage of raw coir pith.

15030210 Studies on physico-chemical characteristics of raw and pre-processed coir pith