Variation in seed characters of Magnolia officinalis from different locations.

The length,width,thickness,length/width ratio and 100-seed weight of Magnolia officinalis seeds from 15 natural distribution regions in China were measured and their germination rates were tested.The results showed that there were significant differences among seeds from different region in seed characters and 100-seed weight.Correlation analysis between seed characters and geographical climatic factors showed that the main variation was of geographical locations.The annual mean temperature,annual precipitation and frost-free period were the leading ecological factors restricting the seed variation.The results of test showed that there were significant differences in germination rates among different seed sources.The seeds from Ningqiang had the highest germination rate,while that from Kaixian the minimum.The seeds from Jingning,Wuyishan and Longsheng had high germination potential.According to cluster analysis on 5 trait-location mean values including seed size and quality and geographical climatic factors,the Magnolia officinalis from 15 natural distribution regions could be divided into 2 provenance regions,i.e.south-east M.officinalis provenance region and north-west provenance region.