几种菊科入侵植物和非入侵植物的化感作用比较

以萝卜为受体,采用培养皿法比较研究了几种菊科入侵种和非入侵种的化感潜力。结果表明：入侵种和非入侵种都具有化感作用,且入侵种在高浓度下的化感抑制作用强度不一定都大于非入侵种。在0.2 g.mL-1浓度时,艾蒿和黄鹌菜的综合化感作用强度分别是小飞蓬的2.5和3.1倍;而紫茎泽兰和银胶菊则是小飞蓬的3.8和3.5倍。而不同植物浸提液对萝卜的不同检测指标影响不同。其中,紫茎泽兰对萝卜种子发芽和幼苗生长的影响主要表现为化感抑制作用。银胶菊和除0.025 g.mL-1外的黄鹌菜各浸提液都使萝卜种子萌发受较强的抑制,且抑制强度随浸提液浓度的升高而增大,而对幼苗生长则表现为＂低促高抑＂的规律。小飞蓬和苦荬菜对萝卜种子萌发和幼苗根长为抑制作用,但对其苗高和鲜质量为促进作用。除0.025 g.mL-1外,艾蒿对萝卜种子萌发和幼苗根长有较强的抵制,对其苗高和鲜质量则呈＂低促高抑＂的规律。

Compare the allelopathy of some invasive and non-invasive Compositae species

To compare the allelopathy of invasive and non-invasive species,the allelopathic potential of aqueous extracts of some Compositae plants to radish were studied by using indoor Petri dish bioassay method.The results showed that both invasive and non-invasive species had allelopathic potential.And the allelopathic inhibition effect of invasive species wasn＇t entirely stronger than that of non-invasive species.When the concentration of aqueous extracts was 0.2 g？ml-1,the synthetical allelopathic effect indices of Artemisia argyi and Youngia japonica were 2.5 and 3.1 times that of Conyza canadensis,while those indices of Eupatorium adeno-phorum and Parthenium hysterophoru were 3.8 and 3.5 times that of Conyza canadensis,respectively.And besides,it varied from the effects of different plant aqueous extracts on the different examination indexes of radish.Concretely,Eupatorium adenophorum mainly had significantly inhibitory effects on the radish seed germination and seedling growth.The aqueous extracts of Parthenium hysterophoru and Youngia japonica mostly exhibited inhibitory effects on the radish seed germination,while they accelerated the radish seedling growth with low volatile concentration and inhabited it with high concentration.Conyza canadensis and Ixeris chinensis inhabited the radish seed germination and root growth but accelerated its seedling height and fresh weight.For Artemisia argyi,its effects on radish seed germination and root growth were similar to the preceding two,but it exhibited allelopathic inhibition under high concentration and allelopathic stimulation under low concentration to radish seedling height and fresh weight.