| The revisory method CTAB was used to extract DNA from Amentotaxus Argotaenia (Hance) Pilger plant-leaves which were gathered from lushan Mountain, Jinggangshan Mountain, Longmen of Tonggu, Mingyueshan Mountain and Junfeng Mountain in Yichun and Guanshan Mountain in Yifeng. The recycling parameters were optimized and optimal reaction system suitable for RAPD-PCR and ISSR-PCR amplification was established in the paper. RAPD assessment of genetic variation and genetic diversity in 74 species and ISSR assessment of 66 species were carried out.The results show that acetone in the solution for extraction affected greatly on the abstraction of genomic DNA, Which can low the rate of the output and rise the purity of output. Simultaneously, the extraction time affected rarely on the abstraction of genomic DNA. The optimal reaction system of RAPD for Amentotaxus argotaenia was determined as follows: 2ul lOxTaq polymerase corresponding buffer, template DNA 70ng, Mg~2+ 2.0mmol/L, dNTP 0.2mmol/L, primer 0.60μmol/L and Taq DNA polymerase 1.5U separately in total 20μl reaction volume; The optical amplification program was also obtained: 94℃ 5min, lcycle; 94℃ 1min, 36℃ 1min, 72℃ 2min, 40 cycles; 72℃ 10min, 1 cycle. The optimal ISSR-PCR conditions in the experiments were as the following: in 20μl PCR reaction system, 2μl 10×DNA Taq polymerase buffer, 1.8U Taq DNA polymerase, 0.2μmol/1 primer, 0.18 mmol/L dNTP, 1.5~ 2.5mmol/lMgCl2, 10ng/μl temper DNA; The optical amplification program was also obtained: 94℃ 5min, lcycle; 94℃ 30 S, 50 ℃ (46℃-54 ℃ ) 45S, 72 ℃ 1.5min, 35 cycles; 72 ℃ 7min, 1 cycle; 4 ℃ 30min, 1 cycle.120 PAPD primers were used to screen the suitable primers with 5 samples from different populations for assessing the genetic diversity of Amentotaxus argotaenia, of which 12 PAPD primers with high resolution and multiple polymorphic bands were screened. The 12 PAPD primers were empolyed to test the genetic diversity of 74 samples from 8 populations. The total 90 PAPD bands were amplified, 51 of which was polymorphic bands. The percentage of polymorphic bands is 83.61%. One hundred ISSR primers were used to screen the suitable primers with 7 samples fromdifferent populations for assessing the genetic diversity of Amentotaxus argotaenia, of which 10 ISSR primers with high resolution and multiple polymorphic bands were screened and was empolyed to test the genetic diversity of 66 samples from 8 populations. The total 61 ISSR bands were amplified, 51 of which was polymorphic bands. The percentage of polymorphic bands is 83.61%.0,1 matrix constructed according to amplified maps was inputed into computer. As for RAPD data, the result of POPGENE analysis indicated that the level of genetic diversity of Amentotaxus argotaenia was high. The DK population possessed the highest level of genetic diversity (PPL=74.44%, h=0.3178, 1=0.4567), while the Lushan Mountain population (PPL=10%, h=0.0414,1=0.0605) exhibited lower levels of genetic diversity. Nei s genetic diversity analysis and analysis of molecular variance (AMOVA) showed that there was a certain level of genetic differentiation (Gst= 0.2619, ?st=19.89%) among the eight populations. The differentiation may be caused by barriers of gene flow. The dendrograms of genetic relationships among populations was constructed based on Nei s genetic distance. The Xiping and Suichuan populations clustered in a clade, then lushan population and them clade, which showed lushan population was progeny of them.As far as ISSR data is concerned, the result of POPGENE analysis indicated the levels of genetic variation of Amentotaxus argotaenia (Ht=0.2931, Hs=0.2135) was higher than other endangered or relict gymnosperms. Nei s genetic diversity analysis of molecular variance (AMOVA) showed that there was a certain level of genetic differentiation (Gst=0.2710,Ost=26.62%) among the eight populations. The dendrograms of genetic relationships among populations was constructed based on Nei s genetic distance. The Daxikang and Xiaoxikang populations clustered in a clade, the Tonggu and Junfeng populations had a close relationship and the Xiping and Suichuan populations clustered in a claede too. The correlation between genetic distance and geographic distance was supported.In view of the genetic information available for Amentotaxus argotaenia, it was suggested that the Daxikang and Xiaoxikang populations should be incorporated into Guanshanshan Mountain nature reserve to long-timely and effectively preserve theliving space of Amentotaxus argotaenia. Simutaneously, adult plants or seedings mutually should cross-transplant among population to enchance the gene flow. By the means, the genetic diversity resources of species can be preserved to the greatest extent.
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