Individual Variation of Gutta-percha Content in Barks of Eucommia ulmoides Oliv.

Individual variation of gutta-percha content in barks of Eucommia ulmoides and the correlations between gutta-percha content character in bark and several macroscopic properties were systematically studied by means of selecting the typical plants and random sampling. The result showed that the differences of DBH (diameter at breast height), the bark thickness and gutta-percha content in bark were in significant level among various clones. The gutta-percha content rate among different Eucommia clones had a significant negative relation with the phellem thickness and the ratio of phellem to bark thickness and it also negatively related to DBH, which indicated that larger DBH and thicker phellem led to less gutta-percha accumulations. Gutta-percha content in unit volume of bark related positively significantly with gutta-percha content rate in bark and volume weight of the bark.