Activity And GC-MS Identification Of Endogenous Inhibitory Substance In The Seed Of Paris Polyphylla Var. Yunnanensis

Paris polyphylla var.yunnanensis?Franch.?Hand.-Mazz is a precious traditional Chinese herbal medicine with beautiful and peculiar flower shape,full and bright red fruit,which has high economic value.The main breeding methods are tissue culture,rhizome propagation and seed propagation.Among them,seed propagation is the most reliable and efficient breeding method in the artificial seedling breeding work.However,in the process of seedling raising,it takes 18 months for the seed to be unearthed.In this paper,based on seed dormancy,bioassay and the appraisal of inhibiting substance,it is discussed that the relationship between endogenous inhibitors and seed dormancy of Paris polyphylla var.yunnanensis.It provides the basis for further study on dormancy mechanism and breaking dormancy technology of Paris polyphylla var.yunnanensis seed.The results are summarized as follows:1.Anatomical observation showed that the majority of the fresh seeds of Paris polyphylla var.yunnanensis embryo is small,embedded in the endosperm.The seed germination were not found through both tissue culture and wet sand culture;The good quality seeds has high viability.There is no permeability barrier of the endosperm;Paris polyphylla var.yunnanensis seed coat and endosperm methanol extract significantly inhibite the germination of Brassica campestris L.ssp.Pekinensis,Triticum aestivum and Vigna radiata seeds.It shows that seed dormancy of Paris polyphylla var.yunnanensis is depending on its after-ripening and the inner inhibitory substances in different parts of the seed.2.There are endogenous inhibitory both in seed coat and endosperm,and the inhibitory action from endosperm is stronger than seed coat.Three receptor plant seedlings show different sensibility to the endogenous inhibitory of seed coat and endosperm,Brassica campestris L.ssp.Pekinensis?Oil?seeds are significantly more sensitive than Triticum aestivum?Starch?seeds and Vigna radiate?Protein?seeds.Inhibition by Paris polyphylla var.yunnanensis seed coat and endosperm methanol extraction,the strength of growth indexes about seed germination and seedling are rating as:germination rate>seedling root length>seedling height>fresh weight.3.The inhibitory substances in the seed coat and endosperm cause the physiological response of the three receptor plant seedlings,and start the antioxidant enzyme system.With the increase of seed coat methanol extract concentration,the activity of superoxide dismutase?SOD?and peroxidase?Pod?increased first and then decreased,while catalase?CAT?activity continued to decline.After treatment with methanol extract from endosperm,the activity of SOD and POD were significantly increased compared with control group,and CAT activity decreased significantly.With the increase of seed coat and endosperm methanol extract concentration,the activity of amylase,acid phosphatase,protease decreased significantly.It demonstrated that the endogenous inhibitors in the seed coat and endosperm of Paris polyphylla var.yunnanensis have a significant inhibitory effect on the decomposition and utilization of starch,fat,protein,so that the seed germination is inhibited.4.Through the bioassay research about the seed coat and endosperm extracts separation phases of Paris polyphylla var.yunnanensis,the results showed that the methanol extract had the most inhibitory effect and was the best solvent for the bioactivity determination.Ethyl acetate was the second,petroleum ether was the weakest.The inhibitory effect of the seed coat and endosperm on the seed germination and growth index was in the order of root growth>germination rate>seedling height.5.The results of GC-MS analysis showed that there were 19 organic compounds in the seed coat extract and 22 in the endosperm extract.These compounds were mainly organic acids,esters and phenols.The relative content of organic acids is the highest.The most similar compounds are palmitic acid(C₁₆H₃₂O₂),benzoic acid?C₇H₆O₂?,cinnamic acid?C₉H₈O₂?,acetic acid?C₂H₄O₂?,butyrate?C₄H₈O₂?,octanoic acid(C₈H₁₆O₂),phenol?C₆H₆O?,methyleugenol(C₁₁H₁₄O₂),dibutyl phthalate(C₁₆H₂₂O₄)et al.The species and quantity of organic compounds in different parts of Paris polyphylla var.yunnanensis seed are different,and the kinds of organic compounds extracted from endosperm are more than those in seed coat.The kinds of organic compounds isolated from ethyl acetate extract were obviously more than those of other extracts,and the content of organic compounds in methanol extract was significantly higher than that in other extracts.