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To explore the mint (Mentha haplocalyx Briq.) Tolerance and enrichment of chromium physiological mechanisms, pot method, to study different concentrations at different time. Cr6 processing antioxidant enzymes (SOD, POD, CAT) activity in the different organs of the mint, malondialdehyde (MDA), the chromium content of the subcellular fractions chromium distribution and chlorophyll content, root activity, photosynthetic rate. The results show that presents the trend first and then decreased with increasing of Cr6 quality concentration, SOD, POD, CAT, three enzyme activities, in a the Cr6 mass concentration of 40mg / L, which all peaks; 50 days, three enzymes The activity of the overall growth trend. With the strengthening of of Cr6 stress concentration and time, MDA has been showing a rising trend, root, stem, leaf MDA content variations are 1.85 times, 2.03 times, 1.07 times; 2.31 times, 2.52 times and 1.59 times. At the subcellular level, the subcellular distribution of chromium in the roots followed by cell wall gt; plastid gt; nucleus gt; mitochondrial gt; soluble fraction, and the highest chromium content in the root cells is cell wall content of 57% to 75 %; subcellular distribution of chromium in the leaves followed soluble fraction gt; cell wall gt; chloroplast gt; nucleus gt; mitochondria, the chromium content of the leaves in the soluble fraction (including soluble substances and vacuole) accounted for 50% of the chromium content of the whole cell ~ 60%, the highest subcellular fractions. Organ level, the three organs compared root leaves, the chromium content in the organs on the chromium content in the three organs the highest total chromium content of the whole plant, up to 93%, the lowest 80%, followed by stem gt; according to the difference compared, the greater the concentration of stress quality, the longer the time, the higher the chromium content in the organs. Treated for 20 days and 50 days after the root activity low 22.41% respectively, compared with the control root activity, 29.12%, 24.55%, 44.31% and 25.19%, 47.80%, 48.26%, 63.37%, and the processing of various concentrations of root activity tended to decrease . Under 10mg/LCr6 mass concentration, chlorophyll a, chlorophyll b, carotenoid content higher than that of the control, under 20 ~ 60mg / L Cr6 mass concentration, chlorophyll a, chlorophyll b, carotenoid content lower than that of the control, The downward trend. Cr6 mass concentration stress, mint leaf net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 mole fraction (Ci) and transpiration rate (Tr) values ??with the control compared to most of the significant difference. Mint body's antioxidant enzymes, the vacuole in of chromium tolerance and detoxification in the cell wall of the root and leaves play an important role.
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