Karyomorphological Studies in Some Species ofParnassiaL. (Saxifragaceaes.l.) in East Asia and Intraspecific Polyploidy ofP. palustrisL.

[摘要] Karyomorphological information is one of the most important characters for cytotaxonomy. We described karyomorphology of 14 species ofParnassiain East Asia. They had commonly the resting chromosomes of the simple chromocenter type and the mitotic prophase chromosomes of the proximal type. The somatic chromosome number of2n=14was shown in three species, that of2n=18was shown in six species, that of2n=18or 36 was shown in two species, that of2n=32was shown in one species, that of2n=36or 36+1~8 s was shown in one species, and that of2n=18, 27, 36 or 45 was shown in one species. They were commonly monomodal (gradual) decrease in length from the largest to the smallest chromosomes. However, their absolute chromosome sizes were different from each other. Average chromosome sizes were recognized as three types small (1.21 μm), medium (1.7–2.36 μm), and large (3.1–3.75 μm).Parnassia palustrisshowed four cytotypes that could be likely cytogeographically correlated with habitats, polyploidy, and sizes of pollen grains.

[学科分类] 植物学