连作对当归生长的障碍效应及机制研究

Effects of continuous cropping obstacle on growth of Angelica sinensis and its mechanism

目的:通过研究连作当归的生理生化效应,探讨当归的连作障碍机制。方法:测定分析当归的生长指标、叶片光合参数、保护酶活性等生理生化指标和产量、品质的变化。结果:连作导致当归生长发育受阻,药材产量、挥发油含量和浸出物含量下降。连作胁迫使叶片光合色素(Chla,Chlb,Chla/Chlb)含量降低,光合速率降低;叶片保护酶SOD,POD,CAT活性降低;叶片膜脂过氧化作用增强,MDA、脯氨酸和可溶性糖含量增加。结论:连作通过降低植株保护酶活性引起活性氧代谢失调,导致活性氧积累和膜脂过氧化损伤。这种影响的外在表现是植株光合色素含量降低,光合作用强度下降,干物质积累减少,可溶性糖含量升高,生长受抑,病害严重,产量和品质下降。

Objective： To study the effects of continuous cropping obstacles on growth of Angelica sinensis.Method： The growth indexes,photosynthetic characteristic,activity of leaf protective enzymes,and the yield,essential oil content and extract content were determined.Result： Continuous cropping decreased the growth and the yield,essential oil content,extract content of A.sinensis.Photosynthetic pigment,which include Chla and Chlb,and photosynthetic rate of A.sinensis leaves decreased.Activity of leaf SOD,POD and CAT were also inhibited.The content of proline,soluble sugar and MDA increased.Conclusion： Through decreasing the activity of protective enzymes and their ability of cleaning free radical,continuous cropping made free radical remain in plant so that induced membrane lipid peroxidization,electrolytic leakage became heavier,content of proline and soluble sugar increased.The external manifestation of this influences were that plant growth was inhibited,content of photosynthetic pigments decreased,so did the intensity of photosynthesis and respiration,content of dry mass.