Abstract:

Based on field investigation and analysis of the natural distribution of Quercus mongolica in China, eight populations of Q. mongolica (Daxing’anling, Jiaying, Shuangyashan in Heilongjiang Province, Jiaohe in Jilin Province, Daqinggou in Inner Mongolia Autonomous Region, Kuandian in Liaoning Province, Wulingshan and Zanhuang in Hebei Province) were selected and investigated. Material collection and measurement were made on the eight populations(thirty individual plants each population). Morphological diversities among/within populations were discussed on the basis of traits such as the apical bud, the leaf blade, the acorn, and the cupule. Analysis of variance for all traits showed that there was significantly difference among populations and among individuals within populations.The mean phenotypic differentiation coefficient(V_ST)showed that the variation among populations(53.97%) was slightly higher than that within populations. The acorn became larger, the shape of the acorn changed from nearly spherical to oblong, and the shape of leaf blade from long obovoid to broadly obovoid, upon increase of the longitude and latitude.The acorn got smaller as the altitude became higher. There existed correlations among the morphological traits mentioned above. According to the UPGMA cluster analysis based on the Euclidean distance, the populations of Q.mongolica investigated could be divided into four groups.

Key words: Quercus mongolica, natural population, phenotypic diversity