Abstract: The laticifers of the Brazil rubber trees(Hevea brasilinsis)were investigated.The resultsindicated that there was significant decrease of the rows and the density of the laticifers ofthe phloem of Brazil rubber trees with increase of the latitude or altitude.There weremuch more rows of laticifers and the denser laticifers at the western and southern sides ofthe phloem than at the northern side at the same height of the rubber tree.

Key words: Sinorhizobium fredii, Diversity, Clustering analysis