作 者 ：Wei Ping-he, Chen Wei-pei, Chen Rui-yang
期 刊 ：植物分类学报 1994年 4期
Keywords:Chromosome, Karyotype, Nymphaeaceae,
Abstract:
The present paper reports the karyotypes of six species in the family
Nymphaeaceae (sensu lato), and discusses its taxonomic position. Results of the karyotype
analysis are as follows: (1) Nelumbo nucifera Gaertn. was found to have the karyotype 2n
= 16 = 9sm +4m + 3st, which belongs to 2B type. There was one heterozygous pair and one
pair of large subterminal chromosomes in the complement. (2) Victoria cruziana Orbign. was
shown to have the karyotype 2n= 24 = 8sm+8m+ 8T, which belongs to 2A type. The
chromosomes were the largest in the Nymphaeaceae. (3) Nymphaea stellata Willd. wag of
2n =28. No. 1 chromosome possessed two satellites. The chromosomes were the smallest in
the Nymphaeaceae. (4) Nuphar pumilum (Timm.) DC. had the karyotype 2n=34=18m
4+16sm, which belongs to 2A type. One satellite was on No. 8 chromosome and the other
was easily detached (5) Euryale fero Salisb. ex Konig et Sims. was of 2n=58. The 58
chromosomes were in 29 pairs. Its chromosomes were small. No. 1 chromosome possessed
two satellites. (6) Brasenia schreberi J. F. Gmel. was shown to have 2n=72. The 72 chro-
mosomes were in 36 pairs, which could be classified into 4 pairs of large chromosomes. 12
pairs of medium-sized ones and 20 pairs of small ones. Three satellites could be seen in some
karyotypes. Except N. nucifera, the karyotypes of all the species are first reported. The
great differences in the karyotype and morphological characteristics between Nelumbo and
the other members of the Nymphaeaceae suggest that the Nymphaeaceae (sensu lato) be di-
vided into two separate orders, namely Nelumbonales and Nymphaeales. Nelumbonales con-
tains a single family Nelumbonaceae and a monotypic genus Nelumbo, while the other plants
belonging to the Nymphaeaceae which constitute the order Nymphaeales. Nymphaeales may
also be divided into two separate families, Cabombaceae and Nymphaeaceae. Cabombaceae
containing Brasenia and other genera is the most primitive in the Nymphaeales. Nymphaea,
Euryale, Victoria and Nuphar are included in the Nymphaeaceae.