外源亚精胺对铅胁迫下茶树生长的影响

选取龙井43为材料,采用盆栽试验,研究了外施1.0 mmol·L^-1的亚精胺（Spd）对不同浓度重金属铅（Pb²⁺）胁迫下茶树株高、地径和叶片相关抗氧化酶活性、渗透调节物质含量、丙二醛（MDA）含量、细胞膜透性以及叶绿素含量等生理指标的影响。结果表明,低浓度铅胁迫能够促进茶树生长,而高浓度铅胁迫影响了茶树正常生长;喷施外源亚精胺有效缓解了随着胁迫Pb²⁺浓度升高对茶树造成的伤害,提高了叶片抗氧化酶活性、可溶性蛋白含量和叶绿素含量,降低了叶片脯氨酸（Pro）含量、MDA含量和相对电导率（RC）,从而促进茶树生长。表明外源亚精胺对铅胁迫下茶树生长具有积极的促进作用。

Effects of Exogenous Spermidine on Growth of Tea Plant under Lead Stress

By adopting the pot experiment and using Longjing 43 cultivar as test material, the effects of 1.0 mmol·L^-1 exogenous spermidine on the growth of tea plant, and the physiological indexes in leaves such as the activity of leaf antioxidant enzymes, osmotic adjustment substances content, MDA content, cell membrane permeability and chlorophyll content were investigated under different concentration lead stress. The results showed that: low concentration of lead stress could promote the growth of tea plant, while high concentration of lead stress influence the growth of tea plant. Applying exogenous spermidine could effectively mitigate the damage of tea plant caused by increase of lead stress, promote the growth of tea plant, improve the activity of antioxidative enzyme, soluble protein content, chlorophyll content, and reduced the proline content, MDA content and the relative conductivity, so to promote the growth of tea plant. It suggested that 1.0 mmol·L^-1 exogenous spermidine has a positive role in promoting the growth of tea plant under lead stress.