In order to learn physiological response law to Mn stress and response differences between different organs in Camellia oleifera seedlings, in hydroponic conditions, physiological response features of roots and leaves in C. oleifera seedlings were analyzed and compared by increasing Mn ion concentration to 6 mmol/L in nutrient solution for 20 days. The results show that, under Mn stress, brown speckles appear at the tip and edge of few leaves after 15 days. Compared with CK group, MDA content, SOD activity and POD activity in leaves and roots have significant changes, and the indexes are increased constantly with prolonging stress duration. However, the values of physiological indexes have differences among different organs, both MDA content and SOD activity in leaves are more than those in root, but POD activity in leaves is lower than that in root. Change of SOD activity is much higher than the other two indexes in ifve days. The results indicate that, under Mn stress, the physiological indexes of C. oleifera seedlings synergistically respond to changes of external environment, but different organs suffer stress at different degrees, dominant resistant enzymes and enzyme response speed are different in different organs.%为了解油茶幼苗对锰胁迫的生理响应规律及其不同器官对锰胁迫的响应差异，在水培条件下，将培养液中锰离子浓度提高至6 mmol/L形成锰胁迫，就油茶幼苗根和叶在锰胁迫早期（持续20天）的生理响应特征进行分析与比较。结果发现，锰胁迫第15天后，少数叶片的尖端和边缘出现了褐斑；与对照组相比，处理组幼苗叶与根中的MDA含量、SOD与POD酶活性均发生了显著的变化，且随着处理天数的增加，根和叶的MDA含量、SOD与POD活性均呈增加或增强趋势，但在不同器官中测定的各生理指标值存在差异，如MDA含量叶＞根， SOD活性叶＞根，而POD活性根＞叶；锰胁迫的最初阶段（第0～5天），SOD 活性的变化程度显著大于其他两项生理指标。实验结果说明，在锰胁迫初期，油茶幼苗各生理指标协同响应以应对外界环境的变化，但不同器官所受锰胁迫的毒害程度不同，抗逆境的主导酶以及酶响应的速度都有差异。
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