The Evaluation On The Heavy Metal Content Of Vineyards In The Changsha-Zhuzhou-Xiangtan Area And The Effects Of Cd On The Physiological Characteristics Of The Grape

In this study, the heavy metal content in the vineyard soil and grape organs was detected, then the vineyard soil environmental quality and safety of grape berries were evaluated, based on extensive sampling investigation from the vineyard of Changsha, Zhuzhou, Xiangtan. Meanwhile, combining with potted experiment with Summer black seedless, Wink, and Vitis davidii Foex, the distribution features of Cd in the grape and the effects of Cd stress on the physiological characteristics of the grapes were analyzed. The main results were as follows:(1) The pH value of Vineyard soil was in the range of 3.45～7.19, and most vineyard soil presented acidic in Changsha, Zhuzhou, Xiangtan. The excessive rate of heavy metals in soil showed as the order of Cd> Hg> Cr> As> Pb. Simultaneously, as the most protruding factor, the excessive rate of Cd reached 47.64 percents, and the maximum of single pollution index was 4.02.(2) Heavy metal content in the grape berry was lower than the national standard value on the basis of analysising 263 samples from 93 vineyards. The distribution of Cd in different grape varieties were same:root> vine> leaf> berry, and the Cd accumulation coefficient in the root and vine were dozens of times higher than berries. There are differences in the Cd accumulation capability of grape berries among varieties. The Cd accumulation coefficient of the berry was positively correlated with vines age.(3) The cell structure and organelle of grape leaves did not express obvious injured symptoms at lower Cd2+ concentrations. When Cd2+ concentration achieved 10mg/kg, the leaf cell structure was damaged and showed some abnormal symptoms, such as the membrane structure damaged, the chloroplast deformed, the thylakoid membrane expansioned or loosen, the chloroplast stroma disintegrated, etc. When subjected to Cd2+ treatment, Vitis davidii Foex was more obviously injured than Summer black seedless and Wink in their leave cells.(4) At lower Cd2+ concentrations, the antioxidant enzyme activity of grape leaves was rising, mainly refering to the CAT, SOD and POD. However, with the Cd2+ concentration increased to a certain value, the antioxidant enzyme activity began to decrease. The MDA content in grape leaves was positively correlated with the Cd2+ concentrations, which showed that Cd2+ stress could cause membrane lipid peroxidation. The chlorophyll content and chlorophyll a/b value was negatively correlated with the Cd2+ concentrations.