title: [Relationships between cadmium accumulation and organic acids in leaves of Solanum nigrum L. as a cadmium-hyperaccumulator].
abstract: The influence of different cadmium concentrations on the organic acid level in leaves of the Cd hyperaccumulator, Solanum nigrum L., in particular, the relationship of organic acids with Cd accumulation in S. nigrum was investigated based on the pot-culture experiment. The results showed that the Cd concentration in S. nigrum leaves exceeded 100 microg x g(-1), the threshold value used to define Cd-hyperaccumulators, and the bioaccumulation coefficient of cadmium in shoots of S. nigrum was higher than 1 when Cd concentration in soil was 25 microg x g(-1). The level of organic acids in leaves of S. nigrum had significant differences between the seedling stage and the mature stage. At the seedling stage, the sequence of organic acids in leaves of S. nigrum was acetic acid> tartaric acid> malic acid> citric acid. On the contrary, the accumulation of organic acids in S. nigrum at the mature stage was approximately in the following sequence malic acid> tartaric acid, acetic acid> citric acid. The significant positive correlation between Cd accumulation in leaves of S. nigrum and the concentration of tartaric acid in leaves of S. nigrum was observed at the seedling stage, whereas there was a significant positive correlation between Cd accumulation in leaves of S. nigrum and both acetic and citric acid concentrations at the mature stage. These results indicated that tartaric, acetic and citric acids in leaves of S. nigrum might act as the indication of Cd hyperaccumulation.
authors.affiliation: Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Rui-lian
authors.initials: RL
authors.lastname: Sun
authors.forename: Qi-xing
authors.initials: QX
authors.lastname: Zhou
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
mesh_terms: D019342:Acetic Acid / Q000032:analysis; D002104:Cadmium / Q000378:metabolism*; D008293:Malates / Q000032:analysis; D009930:Organic Chemicals / Q000032:analysis*; D018515:Plant Leaves / Q000378:metabolism*; D032324:Solanum nigrum / Q000378:metabolism*; D013644:Tartrates / Q000032:analysis; D013997:Time Factors
chemical_list: D008293:Malates; D009930:Organic Chemicals; D013644:Tartrates; D002104:Cadmium; C030298:malic acid; D019342:Acetic Acid; C029768:tartaric acid