The Genetic Diversity Study Of Ulmus Pumila L.var.sabulosa And With Notes On Its Reiationship To Ulmus Pumila L.

The research objects are Ulmus pumila L.var.sabulosa which distribution on Hunshandake sandland and Ulmus pumila as comparision.The results of the morphologic,palynology,anatomy and RAPD indicate that:There are same characteristics between Ulmus pumila L.var.sabulosa and U.s pumila in the shape characteristic, pollen shape characteristic and the structure of leaf, but also has differences. The results show that U. pumila L.var.sabulosa has occurred variation in the shape characteristic, pollen shape characteristic and the structure of leaf for acclimatize itself to entironment in the long process of evolvement.118 reproducible loci are yielded based on 14 decamer primers from U.s pumila L.var.sabulosa and U. pumila,of which 83 are polymorphic .The average is 8.4 per decamer primers and the percentage of polymorphic loci equaled 70.34%. The percentage of polymorphic loci, Nei's (1973)gene diversity and Shannon's information index are choosed to estimate the genetic diversity of U. pumila L.var.sabulosa and U. pumila, the results show that U. pumila L.var.sabulosa and U. pumila has higher genetic diversity level, of which U. pumila L.var.sabulosa are higher than U. pumila distinctly. The coefficient of gene differentiation (Gst) based on supposing Hardy-Weinberg among populations is 0.3762, which reveal that 37.62% of the genetic variance existed among populations and 62.38% within populations. There were conform genetic diversity in the six populations, while there were definite gene differentiation for being obstructed. According to the genetic distance and cluster analysis (UPGMA), U. pumila L.var.sabulosa and U. pumila can be sorted into 2 different groups. The results demonstrate that U. pumila L.var.sabulosa has existenced and keeped biggest gene differentiation as endless evolution. There are pertinence between the geography distribution and cluster results of the populations U. pumila L.var.sabulosa and U. pumila.The results demonstrate that U. pumila L.var. sabulosa can be regarded as a variety of U. pumila based on the results of the morphologic, palynology, anatomy and RAPD.