Studies on chemical constituents from leaves of Diplopanax stachyathus Research Status and Endangered Causes of Diplopanax stachyanthus MORPHOLOGICAL CHARCTERS OF THE GENUS DIPLOPANAX HAND.-MAZZ. AND IT‘S SYSTEMATIC IMPLICATION Microsporogenesis and Development of Male Gametophyte in Endangered Species Diplopanax stachyanthus Hand.-Mazz. Studies on the correlation between the branch and leaf morphological variation of Diplopanax stachyanthus and the environmental factors