三种有机酸对镉胁迫下油菜生理特性的影响

Effects of Organic Acids on the Growth of Rape Under Cd Stress

通过盆栽实验研究了低分子量有机酸(酒石酸、柠檬酸、草酸)对镉胁迫下油菜(BrassicaChinensisL.)生长发育的影响.结果表明:加入低浓度(0-0.5mmol.kg-1)酒石酸、柠檬酸、草酸能够使Cd胁迫下的油菜植株干重显著增加、叶绿素含量较0有机酸组分别增加65.3%(P<0.05)、62.9%(P<0.05)和43.8%(P<0.05);叶细胞膜透性及MDA含量降低;油菜抗氧化酶(SOD、POD、CAT)的活性升高.随着有机酸浓度的增加(0.5-1mmol.kg-1),酒石酸缓解作用持续增强,叶细胞膜透性及MDA含量较0有机酸组分别降低66.9%(P>0.05)和18.5%(P>0.05),接近CK组水平;而柠檬酸、草酸的缓解作用却有所降低.三种有机酸对Cd胁迫的缓解顺序为:酒石酸>柠檬酸>草酸.

Through pot cultivation experiments, effects of low-molecular-weight organic acids （tartaric acid, citric acid and oxaltc acid） on the growth of rape under Cd stress were studied. The results showed that at the low concentration of three organic acids （0 -0.5mmol· kg^-1）the dry weight of plant was increased evidently and the concentration of chlorophyll was increased by 65.3 % （P〈 0.05）, 62.9 % （P〈 0.05） and 43.8 % ） （P〈 0.05） Severally, the activities of protective enzyme （SOD,CAT and POD） were enhanced, and the content of MDA and permeability of cell membrane were decreased. However, with increasing concentration of organic acids（0.5 - 1mmol· kg^-1）, the amelioration capability on CA toxicity of tartaric acid was enhanced, the content of MDA and permeability of cell membrane were reduced by 66.9% （P〉0.05） and 18.5% （P〉0.05）, close to CK group level while citric acid and oxaltc acid were reduced. The sequence of the ameliorating effect of three organic acids was： tartaric acid〉citric acid〉oxaltc acid. Key words： organic acids; CA; i＇ape; physiological characteristics