贵州水青冈种质资源的遗传多样性分析及DNA指纹图谱构建

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Abstract： To enhance the conservation and utilization of Fagus longipetiolata germplasm resources in Guizhou province，China，this study developed SSR molecular markers to analyze genetic diversity and construct DNA fingerprints of 10O samples colected from six natural populations.Results showed that all12 polymorphic SSR primer pairs were derived from the chloroplast genome （cpSSR），collectively producing 136 alleles.The mean polymorphism information content （PIC） across the cpSSR loci was 0.767，indicating a high degree of genetic polymorphism. The average number of alleles （Na） ，average number of effective alleles （Ne） ， and average Shannon 'S index （I） for the six populations were 5.125，3.686，and 1.356，respectively， suggesting relatively high genetic diversity.Among the populations，the Duyun population exhibited the highest genetic diversity （ I=1.589 ）.Analysis of molecular variance （AMOVA） indicated that genetic variation mainly occurred within populations （93% ），which was consistent with the low level of population genetic differentiation Fst=0.091 ）. This pattern may be attributed to higher gene flow（ Nm=2.490 ），which likely constrained divergence among populations.Population structure analysis grouped the 10O samples into two genetic subgroups，with the majority exhibiting high genetic purity （ ⩾0.6） . The probability of identity （PI） and probability of identity for siblings（Pisibs） values were 1.11×10-9 and 3.74×10-6 ， respectively， supporting strong discriminatory power of the SSR markers.DNA fingerprints for allsamples were constructed using five core primer pairs.This study provides a scientific basis and technical support for the identification，preservation，breeding and parentage tracing of Fagus longipetiolata in Guizhou province， China.

Key words： Fagus longipetiolata;cpSSR markers;genetic diversity ; population structure;fingerprinting

水青冈（FaguslongipetiolataSeem.）是壳斗科（Fagaceae）水青冈属（Fagus）的高大落叶乔木[1-2]该物种具有分枝高、树体通直且木材坚硬的特点，有较高的经济价值，常被用作家具和农具的原材料[3]，且极具观赏价值。（剩余19956字）