Preliminary Studies On Seed Biological Characteristics And Seed Dormancy Mechanism Of Nanjing Linden (Tilia Miqueliana)

This article mainly take the Nanjing Linden distributed in Emperor hided valley of Anhui Province and Nanjing Forestry University campus as the research object.The Seed biological characteristics were observed and analysed,the seed dormancy mechanism were widespread researched.Results showed,1,The seed biological characteristics showed that the seed is fruit actually,the mesocarp turned linnification,the seed coat is densely covered by the wax,the fruit shell and the seed coat are very hard,and have the certain hindrance function to seed absoring water.The seed plumpness of greenbelt was higher,the seed plumpness of single tree was extremely low. Meanwhile,the size and the weight of seed from different place of production also have the difference.2,Each kind of stratification can not broke the dormancy of the seed with fruit shell. Under the orthogonal L9(34)experiment,obtained the optimum approach of hucked seed to break the dormancy is 70℃hot water soaked seeds 20min,1 000mg·L-1GA3 solution soaked 6h,then 5℃low temperatures stratificated 60d,the germination rate can reach to 14%, which was the best method of break the Nanj ing Linden seed dormancy at present.3,The germination in vitro indicated that,the key factor of inhibiting seed germination is in the endosperm.Removed the endosperm or treated the kernel with gibberelin solution can eliminate the suppression of endosperm.The embryo do not have the determining factors which restrained seed germination.4,The growth inhibitor of Nanjing Linden seed extracted and bioassied showed,growth inhibitor were all contained in the fruit shell,seed coat,and endosperm.The growth inhibitor of fruit shell distributed in the phases of Ether and the phases of Methanol,while the growth inhibitor of seed distributed in the phases of Methanol which inhibit activity is the strongest.