当归自毒作用和其对不同作物的化感效应

Autotoxicity of Angelica sinensis and Allelopathy on Tested Plants

为探讨当归(Angelica sinensis)连作障碍产生的原因和建立合理的轮作制度,在室内采用离体生测方法,研究当归水浸提物对当归、油菜(Brassica campestris)、小麦(Triticum aestivum)和蚕豆(Vicia faba)的化感效应。结果表明:当归具有较强的自毒作用,且自毒作用随浓度增加而增加;当归水浸液浓度为0.0125,0.0250,0.0500和0.1000g.mL-1时,当归发芽率分别为36.25%,5.83%,0.83%和0%。当归水浸提物对3种植物种子萌发均表现为化感抑制作用,并且化感抑制作用随浓度增加而增加,种子萌发次序是油菜>小麦>蚕豆。在同一浓度处理下,对小麦和油菜胚根的化感抑制作用大于胚芽,而对蚕豆胚根的化感抑制作用小于胚芽。油菜和小麦的萌发率和萌发指数大于蚕豆。当归水浸提物对去胚乳小麦幼芽、幼根的平均抑制率分别为5.63%和18.01%;当归对黑暗条件下培养的油菜幼芽、幼根的抑制率分别为16.25%和50.36%,表明当归化感物质对植物非光合作用的抑制作用强于光合作用。因此,当归的自毒作用是造成连作障碍的原因之一;当归对蚕豆的化感作用小于油菜和小麦,蚕豆可以用于当归轮作体系,缓解因自毒作用而引起的连作障碍。

In order to find the succession cropping obstacle of Angelica sinensis（a common traditional Chinese medicinal plant） planting,the effects of aqueous extract from Angelica sinensis root on the germination rates of Angelica sinensis,Brassica campestris,Triticum aestivum,Vicia faba were studied in this paper.Results showed that the autotoxicity of Angelica sinensis was high and increased with increased aqueous concentration.The germination rates of Angelica sinensis were 36.25%,5.83%,0.83% and 0% when the concentrations of aqueous were 0.0125,0.0250,0.0500 and 0.1000 g·mL-1,respectively.Inhibiting effects of Angelica sinensis were ordered as Brassica campestrisTriticum aestivumVicia faba.At the same concentration of aqueous,the inhibiting effects of aqueous on root growth were higher than sprout growth of Brassica campestris and Triticum aestivum,but the effect on root growth were smaller than sprout growth of Vicia faba.And the germination rate and germination index of Vicia faba was higher than those of Brassica campestris and Triticum aestivum.It is concluded that autotoxicity of Angelica sinensis is an obstacle in succession cropping system,and inhibiting effects of Angelica sinensis on Vicia faba were smaller then on Brassica campestris and Triticum aestivum.Vicia faba is an alternative crop for rotation systems to reduce the autotoxicity of Angelica sinensis.