珍稀濒危植物珙桐过氧化物酶活性和丙二醛含量

Peroxidase activity and MDA content of endangered species Davidia involucrata.

采用比色法测定了不同年龄级、部位和叶位珙桐叶的过氧化物酶(POD)活性和丙二醛(MDA)含量,以探讨珙桐的生理生态适应性。结果表明:不同年龄级同一生长时期珙桐叶的POD活性和MDA含量不同,同年龄级同层的POD活性随叶位增大先升后降,MDA含量随叶位增大逐渐升高;同叶位不同层及同层不同叶位的珙桐叶的POD活性和MDA含量不同。珙桐叶POD活性和MDA含量对生长期敏感,同年龄级同叶位的珙桐叶随叶片的生长、衰老,POD活性和MDA含量逐渐升高,即珙桐叶POD活性和MDA含量受生物和非生物因子影响显著,且不同年龄级、叶位、层次存在差异。

To understand the eco-physiological adaptability of Davidia involucrata, the peroxidase （POD） activity and MDA content of D. involucrata leaves of different age class and at different leaf layer and leaf position were analyzed by the method of colorimetry. The results showed that the D. involucrata leaves of different age class but at the same growth phase had different POD activity and MDA content. With increasing leaf position, the POD activity of the leaves of same age class and at the same leaf layer had a decrease after an initial increase, while the MDA content was increasing. The POD activity and MDA content of the leaves at same leaf position but at different leaf layer and those at different leaf position but at same leaf layer also varied. Growth phase had greater effects on the leaf POD activity and MDA content. With the growth and senescence of leaf, the POD activity and MDA content of the leaves of same age class and at same leaf position increased gradually. The POD activity and MDA content of D. involucrata leaves were affected by both biological and non-biological factors, and varied with leaf age class, leaf position, and leaf layer.