| Jug Lans mandshurica is one of the rarer broad-leaved trees in the northeast area of China. But in nowadays, the distribution range and population of Jug Lans mandshuricat reduced markedly, because of the long-term exploitation of it. For studying the germplasm resource of Jug Lans mandshurica, this research gathered 160 wild species and 10 exotic species(from Japan) of it from 17 sampling points in the northeast area of China, where is the main distribution area of Jug Lans mandshurica, as experimental materials. The study extracted the genomic DNA of the 170 samples with the improved method, and analysed 30 samples in each province in the northeast area of China with SRAE Filted 12 pairs of primers which had better polymorphism, and applied them to amplify the genomic DNA of Jug Lans mandshurica. The results:(1) The research applied SRAP to the study of Jug Lans mandshurica for the first time. Established the SRAP-PCR reaction system, and found RNA didn't influence the results of PCR. Optimized five main factors influencing the amplification of PCR, and got the suitable reaction system of 20μL: 60ng of DNA template, 1×buffer, 2.5mM of Mg2+, 0.1mM of dNTPs, 2.0unit of Taq DNA polymerase, 0.3uM of each primer and the best annealing temperature is 49℃.(2) Amplified 90 samples of Jug Lans mandshurica with 12 pairs of primers, and got 342 bands: 28.5 bands for each pair of primers on average, 312 polymorphism bands among them, accounts for 91.22% of the total number, and their sizes are between 200-2500bp.(1) The effective number of alleles of Jug Lans mandshurica in the 17 extant populations are between 1.2048～1.2992. According to effective number of alleles, Shannon diversity index, Nei diversity index, the extant populations of Jiamusi have higher genetic diversity and that of Zuojia have lower genetic diversity.(3) The variation of Jug Lans mandshurica mainly exists in population. The mutation inpopulation accounts for 72.95%, and that among populations accounts for 27.05%(p＜0.001); The genetic distance of Jug Lans mandshurica is related to the distance of populations conspicuously(r=0.6778, p＜0.01).(4) The genetic similarity coefficient of Jug Lans mandshuric in the 17 sampling points are between 0.54～0.94. The 17 points are obviously divided into 2 groups when the genetic similarity coefficient is 0.54. Jug Lans mandshurica in Zuojia were introduced from Japan, and the similarity of seed source between them and Chinese wild species is small. |
