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Laboratory evaluations were made to assess the toxicological and biochemical effect of cypermethrin on fingerlings of common edible freshwater culture carp (Labeo rohita). There was a significant negative (P < 0.05) correlation observed between effective doses of cypermethrin and exposure periods; that is, LC50 values decreased from 0.323 μg/L (6 h) to  > 0.278 μg/L (12 h),  > 0.240 μg/L (18 h) and >0.205 μg/L (24 h). Exposure to sublethal doses of cypermethrin for 24 h and 96 h exposure period caused significant (P < 0.05) time- and dose-dependent alterations in total protein, total free amino acids, nucleic acids, glycogen, pyruvate, and lactate level and in the activity of enzyme protease, alanine aminotransferase, aspartate aminotransferase, acid phosphatases, alkaline phosphatases, acetylcholinesterase, and cytochrome oxidase in liver and muscle tissues of fish. Thus, cypermethrin has potent piscicidal activity against fingerlings of fish Labeo rohita and adversely affects their behavioural patterns, shifting aerobic pathway of fish respiration towards anaerobic pathway and also inhibiting energy production by suppressing ATP synthesis.

The crude extracts of six plants viz, Allium sativum, Capsicum annuum, Artimesia vulgaris, Eupatorium adenophorum, Gaultheria fragrantissima and Phyllanthus emblica were assessed in vitro for activity against fungi Fusarium solani (Mart.) Sacc., the causal agent of dry potato tuber rot. Pathogenecity test was confirmed by inoculating the pathogen into the healthy potato tuber. The assessment of fungitoxicity was carried out by poisoned food technique using ten different concentrations (10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%) against the test fungus. Assessment was carried out in terms of percentage of mycelial growth inhibition of the test fungus. The extracts of all the plant species were found to be effective in inhibiting the mycelial growth. The extract of A. sativum completely inhibited the mycelial growth of the test fungus at the concentration of 40% and the extracts of Capsicum annuum and Phyllanthus emblica inhibited the mycelial growth completely at the concentration of 100%.

Bipolaris sorokiniana (Sacc.) Shoem. is the most economically important foliar blight pathogen of wheat in all warm zones. Essential oil of Zanthoxylum armatum D.C. was used to determine its efficacy against Bipolaris sorokiniana by calculating the percentage of mycelial growth inhibition. The oil showed 25, 37.8, 42.8, 75, 84.5 and 100 percent inhibition of mycelial growth at 5.0, 10.0, 15.0, 20.0, 30.0 and 40.0 μl ml-1 ppm concentrations of essential oil against the test fungus, respectively. Keywords: Essential oil, fungitoxicity doi: 10.3126/eco.v12i0.3206 Ecoprint: An International Journal of Ecology 12: 91-93, 2005