| Abies chensiensis, an endangered plant mainly distributed in Qinling Mountains and Dabashan Mountains, was listed as one of national protected plants at aecond category in China. There have been no reports about the study of seed germinating characteristics of A. chensiensis until now, The objectives of this study were to 1) identify whether cold stratification was effective for breaking the dormancy of Abies chensiensis seeds and find out the optimum duration of cold stratification; 2) determine the optimal temperature for germination and whether altemation temperatures affected germination;3 test whether germination was affected by light;4)choose the better germination texture between silver sand and filter paper.(1) The 1000-seed weight of Abies chensiensis was (32.87±1.01)g , which was higher than other fir seeds, The viability of seedlot was lested by TTC(1.0%). The results of seed dissection, reflecting the high seed abortion. Showed that the percentages of viable seeds, empty seeds and shrumken seeds were 26.00%, 20.50%and 34.75%. respectively. Gemnination lests were performed to determine the effects of cold stratification (4℃ for 0, 14, 21 and 28 days), temperatures (two constant temperatures 20℃, 25℃ and an alternating 20-30℃),light (in light of 8 h·d-1, 100 mol·m-2·s-1 and in darkness)and germination textures (filter paper and silver sand) on germination rate, The results showed that cold stratification could increase seed germination repcenlage and germination energy; the longer the duration of cold stratification, the higherthe germination rate; but the percentages of germination energy did not increase if the duration was longer than the other two temperature regirnes, because a 9-day treatrnent showed 90% of the biggest germination percentage in 25℃; and the alternating 20-30℃ did not increase the germination percentages of the seeds of Abies chensiensis. Compared with those in darkness, light (8h·d-1, 100 mol·s -1) did not increase germination percentages, although it did increase germination energy; light was not indispensable for germination of Abies chensiensis, although it did increase germination energy; light was not indispensable for germination of Abies chensiensis seeds, but did accelerate the process of germination. Great differences were found for germination percenlage and germination energy in two gernianation textures; the percentages of germination and germination energy on silver asnd were 19.75% and 16.755 respectively, but 8.00%on filter paper. The result showes that silver sand was a tetter germination texture for Abies chersiensis seeds than filter paper. Perhaps because silver sand could offer more sufficient water for the germination of bigger seeds such as Abies chensiensis than filter paper.(2) The reproductive phenology was mainly influenced by temperature and sunlight. The dynamics of reproductive module was mainly decided by the biological properties. They started the first reproductive activity at 21a and 40-85a was the best. The key environmental factors are sunlight, soil and moisture. On the application of life table theory, the life table of reproductive module was accomplished. The life table described the key phase of reproductive dynamics process and carried forward the population dynamics to module level. The shape and resident of seedlings were the last and key phase of Abies chensiensis reproduction. The key environmental factor influencing the sexual reproduction of Abies chensiensis sunlight and the activity of human and animals also played an important role.The asexual reproductive abttity of was Abies chensiensis the result of inner and outer factors co action. It showed a lower-higher-lower trend with increase of DBH. The duding ability of the root was stronger, so the stump should be as low as possible and could not overpass 30cm.Sunlight was the key factor influencing budding ability and the survival of seedlings. Among 3 type asexual reproductive means, the contribution ratio of stump was the most and the property of the seedling...
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