窿缘桉根及凋落叶对假臭草种子萌发和幼苗的化感作用

摘要

采用培养皿滤纸发芽法，研究窿缘桉(Eucalyptus exserta )根及其凋落叶不同质量浓度的水浸提液(12.5、25、50和100 g/L)对假臭草种子萌发及其幼苗生长的影响.实验结果表明：窿缘桉根浸提液对假臭草种子萌发及其幼苗的生长无显著作用(P >0.05)，其浓度大小对实验结果的影响不大，而用窿缘桉凋落叶浸提液对假臭草种子进行培养后则表现出极为显著的抑制作用(P<0.01)，且存在明显的剂量效应，其中以100 g/L 浓度的凋落叶浸提液抑制效应最强，其假臭草种子发芽率、发芽指数和活力指数相比对照组分别下降了52.7%、91.5%和100%，在此浓度下，种子失去生长活力，无法萌发为幼苗.%By the method of germination on the paper,this article studied the effects of different mass concentrations of aqueous extract (12.5,25,50 and 100 g/L)from root and leaf litter of Eucalyptus exserta on the seed germination and seedling growth of Eupatorium catarium .The results show that:Root aqueous extracts of Eucalyptus exserta has no significant effects on seed germination and seedling growth of Eupatorium catarium (P >0.05),while leaf litter extract of Eucalyptus exserta has a very marked inbibitional effects on seed germination and seedling growth ofEupatoriumcatarium (P<0.01), which expresses in a dose-dependent manner and the strongest under the concentration of 100 g/L.Under this concentration,the germination percentage,germination index and the vitality index of Eupatorium catarium decrease 52.7 %,91.5 % and 100 % comparing with that under the concentration of the control group respectively(P<0.01),and the seed will lost its vitality and ability to grow into seedling,too.