| Abies beshanzuensis M.H.Wu which is only distributed in Baisanzhu natural reserve, Zhejiang province, is one of the twelve most endangered species in the world and it is also a wild plant of national first class focused protection. To study the plant has very important meanings in such disciplines as botany, geography, climatology, etc. Based on ISSR molecule mark technology, the genetic diversity and genetic variation of different individuals within population were determined, and pollen vitalities, embryo development processes and seed vitality were also studied in this paper. The main results were showed as follows:1. Based on optimized reacting system, 13 primers were screened from 100 ISSR primers, with high stability and repeatability. By using these primers, DNA from 40 individual plants were reporduced, as a result, 91 discernible DNA fragments were generated, of which 39(42.86%) was polymorphic bands, indicating low genetic variations within the species. The level of genetic variation in population originated from seedings (PPB=37.36%) was higher than that in population of old trees (PPB= 16.48%) and population of graft-originated (PPB=20.88%).2. The pollen vitality could not be mensured by benzidine staining method and TTC staining method. But it could be mensured by the method of culture medium. The percentage of pollen bourgeon was 78.5% on the culture medium which consisted of sucrose (5%) and boric acid (20mg/L).3. By observing the paraffin sections, it was indicated that the best time of pollination was the middle and last ten days of May. But the blossom of male cones was from the last ten-day of April to the first ten days of May. So there was reproductive disorder in pollination mechanism of male cones and famle cones. A great deal of ovules were abortive during the function megaspores formed the multicellular formations and the multicellular formations formed macrogametophytes.4. The 1000-seed weight of artificial pollination seeds and of the spontaneouspollination seeds of Abies beshanzuensis was 44.73g and 39.38g. The results of t-test showed that there was significant difference of the seed plumpness between the artificial pollination seeds and the spontaneous pollination.The vitality of the seeds through artificial pollination was 20.2%, while the seeds through spontaneous pollination wasl8.7%.5. The adaptablity of Abies beshanzuensis was poor and the genetic variation was low, so it had higher frangibility than other species of great number population. The sampling action strategies that the old trees were main and the graft trees and seedling trees were assistant was advised to conserve the main germplasm . Adequate germplasm should be conserved timely and effectively for study nowdays and in the future. The genetic diversity of seeding trees was high, the technology system for in vitro reproducing of the megasporophylls, seeds and macrogametophytes of seedling trees should be established. The artificial suplementary pollination should be done between old tree and old tree, old tree and graft tree, graft tree and graft tree. Enforcing studies on breeding and raising seedlings, observing environment continuously were advised. The ture reasons that the macrogametophytes aborted should be further studied.
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