Abstract
Several experiments were carried out to investigate morphology and germination trait of achene in Rumex nipponicus, endangered species, for understanding basic characteristics of this species for its conservation. In our experiments on the germination trait, stratification (low and/or high temperature) and dry-dark treatment were performed; R. nipponicus achene consists of three pieces of perianth with long spines in their edge like R. obtusifolius. However, the former possesses a protuberance in each perianth unlike the latter, which has just one in total. On the other hand, achene of R. nipponicus would not be likely to have deep dormancy because, for instance, the effects of stratification and dry-dark treatment on their germination were not indicated.
