The objectives of the Winter Fog Experiment (WIFEX) over the Indo-Gangetic Plains of India are to develop better now-casting and forecasting of winter fog on various time-and spatial scales. Maximum fog occurrence over northwest India is about 48 days (visibility <1000 m) per year, and it occurs mostly during the December-February time-period. The physical and chemical characteristics of fog, meteorological factors responsible for its genesis, sustenance, intensity and dissipation are poorly understood. Improved understanding on the above aspects is required to develop reliable forecasting models and observational techniques for accurate prediction of the fog events. Extensive sets of comprehensive groundbased instrumentation were deployed at the Indira Gandhi International Airport, New Delhi. Major in situ sensors were deployed to measure surface micrometeorological conditions, radiation balance, turbulence, thermodynamical structure of the surface layer, fog droplet and aerosol microphysics, aerosol optical properties, and aerosol and fog water chemistry to describe the complete environmental conditions under which fog develops. In addition, Weather Forecasting Model coupled with chemistry is planned for fog prediction at a spatial resolution of 2 km. The present study provides an introductory overview of the winter fog field campaign with its unique instrumentation.

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For three consecutive years Bacillus thuringiensis (Bt) transgenic cotton (var. Mech 162) and its isogenic non Bt counterpart were assessed for the risks of transgenic crop on the soil ecosystem under Indian subtropical conditions. To observe effect of Bt cotton on soil biochemical properties, activities of dehydrogenase, alkaline phosphatase, nitrate reductase and urease soil enzymes were assayed at its different growth stages i.e., seedling, vegetative, flowering, bolling and harvesting stages. To observe effect of Bt cotton on soil microorganisms, number of nematodes, collembola and ants representing micro, meso and macrofauna, respectively were observed in Bt and non-Bt cotton plants rhizosphere at different growth stages.Results showed no significant difference (P<0.05) in alkaline phosphatase, nitrate reductase and urease activity between Bt and non-Bt cotton rhizosphere during crop growth period. However, dehydrogenase activity was significantly high (P<0.05) in the Bt cotton rhizosphere as compared to non Bt cotton rhizosphere through out the observation period. At most of the growth stages numbers of micro, meso and macro fauna were more in Bt cotton rhizosphere as compared to non Bt cotton rhizosphere. The temporal and spatial variations observed in number of nematodes, collembola and ants between Bt and non Bt cotton plants rhizosphere were significant. The present study shows that the Mech 162 variety of Bt cotton was not posing any risk to soil microorganisms and soil biochemical properties.

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A soluble and thermostable peroxidase enzyme (POD) was extracted from the leaf of Citrus medica. The enzyme was purified 15.10-fold with a total yield of 28.6% by ammonium sulfate precipitation followed by Sephadex G-100 gel filtration chromatography. The purified enzyme came as a single band on native polyacrylamide gel electrophoresis (PAGE) as well as sodium dodecyl sulfate (SDS) PAGE. The molecular mass of the enzyme was about 32 kD as determined by SDS-PAGE. The enzyme was optimally active at pH 6.0 and 50°C temperature. The enzyme was active in wide range of pH (5.0-8.0) and temperature (30-80°C). From the thermal inactivation studies in the range of 60-75°C, the half-life (t(1/2)) values of the enzyme ranged from 8 to 173 min. The inactivation energy (Ea) value of POD was estimated to be 21.7 kcal mol(-1). The Km values for guaiacol and H(2)O(2) were 8 mM and 1.8 mM, respectively. This enzyme was activated by some metals and reagents such as Ca(2+), Cu(2+), Mg(2+), Co(2+), ferulic acid, and indole acetic acid (IAA), while it was inhibited by Fe(2+), Zn(2+), Hg(2+), and Mn(2+), L-cysteine, L-proline, and protocatechuic acid.

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Abstract. Transgenic crops are new products of agriculture biotechnology. The environmental risks and benefits of transgenic crops are topic of hot debate. Current agriculture management practices and ecosystems have their own impacts on the environment and further any additional negative effect of transgenic crops may mitigate their positive impacts as well as increase the background value of negative impacts due to new agriculture practices. Most of the risk assessment studies on transgenic plants have done observations on changes in their respective aboveground environment and its biota. Very few reports are available on the impacts of transgenic plants or their products (that they release in soil) on soil biota (both invertebrates and. microorganisms) and soil processes mediated by them. However, observations of these studies were not delivering anything conclusively and creating state of confusion also regarding impact of transgenic plants on soil ecosystem. As some of the studies suggested that If production and release of the transgene products from transgenic plants through different routes in soil exceed to its consumption/ biodegradation, may lead to their accumulation beyond threshold levels, which may have acute as well as chronic effect on soil ecosystem. Impacts of transgenic plants are also dependent upon spatial and temporal environmental variables. Whereas some of the studies observation suggests that transgenic plants don't have any negative impact on soil ecosystem. Keeping this status in background we prepared this manuscript. Our manuscript is divided in two parts, first part comprises review of the available literature on impacts of commercialized transgenic plants on soil ecosystem and its diversity, and in second part keeping above information as background, a framework is proposed for future comparative impact assessment of transgenic plants and its non transgenic isoline on soil ecosystem. In this approach each transgenic crop along with its non-transgenic isoline should be dealt separately according to its construct. The proposed approach is precautionary at each step, if there is any doubt at any stage they should be clarified by repetition of experiments. This approach will be helpful in filling of information gaps, which still exists in impact assessment studies of transgenic plants on soil ecosystem. This approach suggested monitoring should be carried out prior as well as post release of transgenic plants. Impact assessment of transgenic plants with respect to soil ecosystem should be made mandatory in current regulatory framework of transgenic crops throughout the world, to assure the use of transgenic technology without affecting the diversity and functioning of soil ecosystem.