采用大田试验研究了两种化学催熟剂(敌草快和农达)对生长后期油菜角果的叶绿素含量、抗氧化酶系统(CAT、SOD、POD活性)、细胞膜透性及MDA含量的影响.结果表明:采用敌草快催熟,油菜角果皮叶绿素含量下降,SOD、POD、CAT活性及细胞膜透性和MDA含量显著提高,导致角果膜脂过氧化,且作用强度随处理浓度的增加而增加;采用农达催熟,油菜角果皮叶绿素含量所受影响较小,SOD、POD和CAT活性上升缓慢,细胞膜透性和MDA含量增加不明显.随着催熟时间的推移,油菜角果保护酶活性受到不同程度的抑制,这可能与催熟剂干扰酶系统分子结构有关.
A field experiment was conducted to study the effects of ripeners Diguat and Roundup on the chlorophyll content, activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), cell membrane permeability, and malondialdehyde (MDA) content of rapeseed pods. Under effects of Diquat, the chlorophyll content decreased, while the activities of SOD, POD, and CAT, cell membrane permeability, and MDA content increased significantly, leading to the peroxidation of membrane lipid. These effects increased with increasing Diquat concentration. After treated with Roundup, the chlorophyll content had less change, activities of SOD, POD, and CAT increased slowly, and cell membrane permeability and MDA content had no obvious increase. With the increasing time of ripeners treatment, the activities of protective enzymes were inhibited to different degree, possibly due to the changes of molecular structure of antioxidant enzyme system under effects of the ripeners.