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Phytoremediation is one of the safest and sustainable approaches to reclaim metal contaminated soil. The present study assessed the phytoremediation potential of lemongrass (Cymbopogon flexuosus Stapf.) by growing it on soil mixed with different concentrations of tannery sludge i.e., 5, 10 and 15% regarded as 5% TS + S, 10%TS + S, and 15% TS + S whereas the soil without tannery sludge was taken as control (0%TS + S). After 35 days of growth, the plants were harvested to record various morpho-physiological attributes and accumulation of various heavy metals in above and below ground plant parts. Results revealed that soil mixed with TS reduced the morphological attributes i.e., the fresh weight, dry weight, number of roots, number of leaves, number of tillers, and shoot length up to 37.50, 26.86, 23.46, 56.25, 16.13 and 19.31%. Moreover, tannery sludge application enhanced the free radicals i.e., 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and regulated the antioxidant activities. Overall metal uptake was higher in the root than shoot whereas the amount of heavy metals uptake by plants was the highest at 15% concentration. The trend of metal uptake was recorded as: Cr > Cd > Cu > Mg > Fe > Zn > Ni > Pb. [ABSTRACT FROM AUTHOR]

We investigated salt toxicity effects and related physiological as well as anatomical changes for adaptation in Cynodon dactylon. Eleven ecotypes from different areas of Pakistan were examined for their survival capacity in a controlled environment. The experiment was designed in a two factor Completely Randomized Design (ecotypes and 4 salt levels 0, 100, 200, 300 mM NaCl). Differently adaptive populations displayed specific structural and functional adaptations with respect to photosynthesis and photosynthetic pigments to withstand salinity. The ecotypes from saline and waterlogged areas exhibited higher Photosynthetic rate to same level of increase in salinity level. Transpiration rate of all ecotypes showed variations with different salinity levels and stomatal conductance increased in all ecotypes with increasing salinity. Similarly, all ecotypes responded significantly as far as chlorophyll contents were concerned. Most ecotypes consistently showed high leaf blade thickness and sclerenchyma thickness with elevated salinity except for plants collected from saline, waterlogged and salt affected wasteland. Different salt levels decreased the metaxylem cell area while phloem area increased in the ecotypes correspondingly. Cynodon ecotypes possessed low abaxial stomatal density at 300 mM salinity. Overall, physiological and anatomical adaptations to saline environments appeared very specific in grasses and supported life cycle under salt stress. [ABSTRACT FROM AUTHOR]