Abstract:

For making clear the geographic variations of gutta percha content in bark of Eucommia ulmoides so as to provide scientific guide for developing high yield gutta percha industrialization base, studies were carried out in 16 producing areas from both the main planting areas and introduction areas. Typical sample tree selection and random selection were applied and integrated extraction was used for the 10-year-old gutta percha content test in this study. The results showed that there were significant differences in DBH (diameter at breast height), barks thickness and gutta percha content among samples from different producing areas. On the whole, gum content decreased gradually along with the latitudinal increase. In the areas with similar latitude, gum content was higher in eastern areas than that in western areas. Higher latitude, more precipitations, higher average annual temperatures and longer frost-free period favored the formation and accumulation of gutta percha in bark, which resulted in higher gum content.

Key words: Bark of Eucommia ulmoides , Gutta percha, Producing area, Variation dynamic