三裂叶蟛蜞菊根系分泌物对菜心的化感作用

Allelopathic potentials of root exudates of Wedelia trilobata on Brassica parachinensis

研究了三裂叶蟛蜞菊根系分泌物对菜心种子萌发和植株生长的影响。结果表明:1)抑制菜心种子萌发效果明显,显著降低了菜心种子的发芽势和发芽率,使菜心幼苗的根长和苗高显著缩短;2)显著降低了菜心植株的叶片叶绿素含量、净光合速率、根系活力、根系鲜质量和地上部鲜质量,株高变矮;3)显著降低了菜心叶片保护酶活性和硝酸还原酶活性,使植株自我保护机制降低,抗逆能力减弱,正常的氮素代谢受阻。

The allelopathic potentials of root exudates of W. trilobata on Chinese cabbage （Brassica parachlnensis Bailey） were studied. Firstly, the root exudates of W. trilobata reduced the seed germination percentage of Chinese cabbage as well as the leaf chlorophyll content, the net photosynthetic rate, the root activity, the fresh root weight, the fresh weight of aerial part and the plant height. Secondly, it significantly inhibited Chinese cabbage＇s activities of catalase, superoxide dismutase and peroxidases. Finally, the root exudates of W. trilobata significantly reduced the activities of nitrate reduetase and the key enzyme concerning nitrogen metabolism in plant. Comprehensively, root exudates of W. trilobata interrupted Chinese cabbage＇s healthy metabolism and normal growth.