【摘要】 随着工农业的发展，重金属污染越来越严重，对环境和人类健康造成了极大的威胁。以1年生香樟幼苗为供试材料，采用土培盆栽的方法，探究了在Cd质量分数为20 mg·kg^-1胁迫时施加不同质量分数(5、10、40 mg·kg^-1)的吲哚乙酸（IAA）对香樟幼苗光合色素、抗氧化酶活性、渗透调节能力的影响。结果表明：Cd胁迫对1年生香樟幼苗生理生化特性均有显著抑制作用，而施加吲哚乙酸可有效缓解Cd对香樟的胁迫，主要表现为吲哚乙酸可增加香樟叶片叶绿素质量分数，降低可溶性糖质量分数、可溶性蛋白质量分数、丙二醛（MDA）质量摩尔浓度、抗坏血酸质量摩尔浓度、谷胱甘肽质量摩尔浓度。外源添加不同质量分数的吲哚乙酸对香樟幼苗Cd胁迫均有不同程度的缓解，其中，施加10 mg·kg^-1吲哚乙酸对香樟Cd胁迫的缓解作用最显著，与仅Cd污染处理未施加IAA相比，叶绿素a、叶绿素b、总叶绿素质量分数分别显著增加60.67%、58.58%、60.13%,可溶性蛋白质量分数、可溶性糖质量分数、丙二醛质量摩尔浓度、抗坏血酸质量摩尔浓度、谷胱甘肽质量摩尔浓度分别显著降低了57.7%、34.89%、22.22%、28.55%、66.03%。外源吲哚乙酸通过缓解由Cd污染导致的氧化胁迫，增强香樟幼苗的光合作用效率，从而提高香樟抗逆境胁迫能力，减少Cd毒害。更多还原

【Abstract】 Using one-year old Cinnamomum camphora seedlings as experimental materials, the effects of indoleacetic acid（IAA） with different mass fractions(5, 10 and 40 mg·kg^-1) on photosynthetic pigments, antioxidant enzyme activity, and osmoregulation ability of C. camphora seedlings under Cd stress of 20 mg·kg^-1 were investigated using soil culture and pot culture methods. The results showed that Cd stress significantly inhibited the physiological and biochemical characteristics of one-year old C. camphora seedlings, while applying IAA could effectively alleviate Cd stress on C. camphora seedlings, mainly manifested by increasing the chlorophyll content of C. camphora leaves, reducing the contents of the soluble sugar, soluble protein, malondialdehyde（MDA）, ascorbic acid, and glutathione. Exogenous addition of different contents of IAA alleviated Cd stress in C. camphora seedlings to varying degrees. Among them, applying 10 mg·kg^-1 IAA had the most significant effect on alleviating Cd stress in C. camphora. Compared with the treatment with only Cd pollution and without IAA, the contents of chlorophyll a, chlorophyll b, and total chlorophyll increased significantly by 60.67%, 58.58% and 60.13%, respectively. The contents of soluble protein, soluble sugar, MDA, ascorbic acid, and glutathione decreased significantly by 57.7%, 34.89%, 22.22%, 28.55% and 66.03%, respectively. Exogenous IAA can alleviate the oxidative stress caused by Cd pollution, enhance the photosynthetic efficiency of C. camphora seedlings, improve the ability of Cinnamomum camphora to resist stress, and thereby reduce Cd toxicity.更多还原