Toxicity of Ocimum suave (Wild basil) crude oil extract on C. maculatus and test on seeds’ viability, was determined in the laboratory using contact toxicity assay method of different concentration 0.02, 0.04, 0.06 and 0.08mg to 20ml of water and 0.00g/20ml of water (control). 20g of cowpea seeds were weighed into separate Petri dishes and 10 adult weevils were inoculated and replicated four times. Each treatment was observed for 96h and recorded after every 12h. The result indicated that the crude oil extract had significant difference (p0.05) in the germination of treated cowpea seeds (Vigna unguiculata L) compared to the untreated control, which shows that the seeds still remained viable. This result showed that O. suave crude oil is effective in the protection of cowpea against cowpea bruchid Callosobruchus maculatus.
In semi arid zone of southern Tamilnadu, India farmers are recognized that planting with multipurpose nitrogen fixing trees including medicinal plants in an agroforestry system for sustainable income generation.To identify the existing agroforestry system. A systematic survey was carried out to find out the nitrogen fixing trees planted in the agroforestry system revealed that a total of economically important 9 tree species belonging to 8 genus of 3 families were commonly cultivated without specific model. These multipurpose usable trees improve soil physical properties, maintain soil organic matter, fix the atmospheric nitrogen and promote nutrient cycling through high amount of litter production, which increase the main crop yield.
Physicochemical parameters and heavy metal content of the Cross River at Afikpo North Local Government Area were determined using standard analytical methods. Four sampling stations were selected along the river and sampled during March to October, 2004. Parameters determined include chloride, conductivity, salinity, ammonium ion, turbidity, pH, dissolved oxygen (DO), biological oxygen demand (BOD5) and total hardness as well as concentration of some heavy metals (Fe, Pb, Cd, Cu, Ni and Zn) in both water, fish and sediment samples. Concentration of heavy metals was determined by atomic absorption spectrophotometry while Na and K were estimated by flame photometry. The river was slightly acidic in Station 1 (pH 6.80) and slightly alkaline in Station 4 (pH 7.47). Turbidity ranged from 16 FTU (in Station 4) to 22.0 FTU (in Station1) with a mean value of 19.250 FTU. The dissolved oxygen range of 5.16 (Station 2) to 8.0 (Station 4) ensures the survival of aquatic organisms. Iron was the most abundant metal both in sediment (99.78 mg/kg), fish (11.45 mg/kg) and water (4.85 mg/L). Cadmium had the lowest concentration in water (0.19 mg/kg) while Zn and Ni had the lowest concentrations in fish (0.18 mg/kg) and sediment (1.55 mg/kg), respectively. Generally the heavy metals had significantly higher (p
Crude extracts of three plants Citrullus colocynthis, Leucas aspera, and Strychnos nux-vomica were screened for their larvicidal activities against the third instar of Culex quinquefasciatus. The mortality rate of the mosquito larvae was evaluated against the three botanicals at different periods of exposure (24h, 48h, and 72h). Hexane, Chloroform and Ethyl acetate were used as solvents for the crude extracts. C. colocynthis showed the maximum larvicidal effect (100% mortality) in 750 ppm and 1000 ppm in hexane extract at 24h period of exposure. L. aspera also showed the same activity in hexane extract at 24 h, while S. nux-vomica showed slightly lower effect.
Pesticide pollution in aquatic environment brings about sudden and drastic changes in aquatic organisms. The indiscriminate use of pesticides in agricultural operations affects the aquatic environment to a greater extent. Pesticides like endosulphan and monocrotophos which are widely used in agriculture affect fish population drastically. In the present study the effect of monocrotophos on the enzymes Acid Phosphatase, alkaline phosphatase and lactate dehydrogenase of Ctenopharygodon idella has been estimated. The activity was found to be decreased significantly due to Pesticide intoxification.