VEGETATIVE DIASPORES IN JAPANESE MOSSES

Abstract

  Among 1183 taxa of mosses recorded in Japan, specialized vegetative diaspores were found in 186 species (15.7%). Eight types of specialized vegetative diaspores (deciduous shoot apices, flagella, caducous branchlets, bulbils (s. str.), rhizoidal tubers, gemmae (s. str.), caducous leaves and endogenous gemmae) have been reported in these gemmiferous species. It is noteworthy that some primitive groups of mosses such as Sphagnales and Andreaeales, have no specialized vegetative diaspores. As a result of the examination of vegetative diaspore production and sexuality in Japanese mosses, the following conclusions were obtained: 1) over half of Japanese moss species (54.1%) are dioicous; 2) specialized vegetative diaspores are found more frequently in dioicous mosses than monoicous ones; 3) monoicous mosses growing under unstable conditions often produce specialized vegetative diaspores.