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Scarcity of water and emission of greenhouse gases (GHGs) are the two key environmental issues affecting crop production in India.Reducing the carbon footprint (CF) and water footprint (WF) of crop production can help to mitigate the environmental hazards that stem from GHG emissions and water scarcity.The CFs and WFs of three major cereal crops,rice,wheat,and maize,were estimated for the year 2014 under the environmental conditions in India,based on national statistics and other data sources.To...  相似文献   
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A deoxy lupane triterpene carboxylic acid, lup-20(29)-en-24-oic acid (1), was isolated from the active chloroform extract of Finlaysonia obovata, a latex exuding mangrove plant. Its structure was evaluated on the basis of different spectroscopic methods, including extensive 1D and 2D NMR spectroscopy. Lup-20(29)-en-24-oic acid (1) has shown moderate antimicrobial activity, against some fish pathogens.  相似文献   
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Distribution of aluminum (Al) within plant components and Al-induced changes in cell wall polysaccharides in root tips of Eucalyptus camaldulensis Dehnh. seedlings were compared with those of Melaleuca cajuputi Powell. In E. camaldulensis , 0.5 mM Al (pH 4.2 for 40 d) reduced plant dry weight by 50%, increased callose concentration in the root tips and induced leaf necrosis. In comparison with M. cajuputi , Al concentrations were higher in roots and leaves of E. camaldulensis on both a fresh weight basis and in the cell sap, but were lower in the cell wall. Al increased pectin, hemicellulose and cellulose concentration in the cell walls of E. camaldulensis root tips. Al-induced leaf necrosis and growth reduction in E. camaldulensis is discussed in the context of potentially toxic concentrations of Al in plant tissue and changes in polysaccharide content which could reduce water and nutrient uptake and cell wall extensibility in roots.  相似文献   
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An experiment was conducted to examine the effect of CO2 enrichment on the nitrate uptake, nitrate reduction activity, and translocation of assimilated-N from leaves at varying levels of nitrogen nutrition in soybean using 15N tracer technique. CO2 enrichment significantly increased the plant biomass, apparent leaf photosynthesis, sugar and starch contents of leaves, and reduced-N contents of the plant organs only when the plants were grown at high levels of nitrogen. A high supply of nitrogen enhanced plant growth and increased the reduced-N content of the plant organs, but its effect on the carbohydrate contents and photosynthetic rate were not significant. However, the combination of high CO2 and high nitrogen levels led to an additive effect on all these parameters. The nitrate reductase activity increased temporarily for a short period of time by CO2 enrichment and high nitrogen levels. 15N tracer studies indicated that the increase in the amount of reduced-N by CO2 enrichment was derived from nitrate-N and not from fixed-N of the plant. To examine the translocation of reduced-N from the leaf in more detail, another experiment was conducted by feeding the plants with 15NO3-N through a terminal leaflet of an upper trifoliated leaf under depodding and/or CO2 enrichment conditions. The export rate of 15N from the terminal leaflet to other plant parts decreased by depodding, but it increased by CO2 enrichment. CO2 enrichment increased the percentage of plant 15N in the stem and / or pods. Depodding increased the percentage of plant 15N in the leaf and stem. The results suggested that the increase in the leaf nitrate reduction activity by CO2 enrichment was due to the increase of the translocation of reduced-N from leaves through the strengthening of the sink activity of pods and / or stem for reduced-N.  相似文献   
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