Study on Dormancy Mechanism and Breaking Dormancy Method of &i&Viburnum sargentii&/i& Seeds

摘要

Under untreated conditions, the germination rate of Viburnum sargentii seeds is very low. By exploring the relationship between the dynamic changes of physicochemical indicators and endogenous hormones and seed germination during the dormancy and germination of Viburnum sargentii seeds, the mechanism of seed germination of Viburnum sargentii was determined, which provided a theoretical basis for its extensive promotion and development. The contents of soluble sugar and soluble starch were determined by anthrone colorimetry. The soluble protein was determined by Coomassie brilliant blue G-250 staining. The activity of polyphenol oxidase (PPO) was determined by NBT reduction method. The peroxidase (POD) was determined by guaiacol method. And the endogenous hormones ZA, IAA, ABA, GA _( 3 ) were determined by liquid chromatography. Results show : 1) Under natural conditions, the seeds of Viburnum sargentii are difficult to germinate. 2) Under sand storage for 8 months, the germination rate of untreated seeds was 33%. Puncture and peeling treatment could significantly increase the germination rate, and the germination rate of seeds treated with puncture was 92%, and that treated with peel was 98%. 3) Seed germination was accompanied by the decrease in macromolecular substances such as soluble sugar, soluble starch, and soluble protein. 4) The dynamic changes of hormones during seed germination conform to the hypothesis of “three factors”. 5) The treatment of puncture and peeling increased the content of endogenous hormones promoting germination, decreased the endogenous hormones inhibiting seed germination, and increased the ratio of (IAA + GA + ZR)/ABA or GA/ABA. The seeds of Viburnum sargentii have obvious dormancy characteristics. Under the condition of sand storage, both pricking and peeling treatment can effectively promote the process of breaking dormancy, and the effect of peeling treatment is better.