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沙参属10个种的染色体研究

傅承新, 刘鸣远   

  1.  (哈尔滨师范大学生物系,哈尔滨)
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:1987-06-18 发布日期:1987-06-18
  • 通讯作者: 傅承新

Chromosome Studies of 10 Chinese Species of Adenophora Fisch.

Fu Cheng-Xin, Liu Ming-Yuan   

  1. (Department of Biology, Harbin Normal Universisy, Harbin)
  • Received:1900-01-01 Revised:1900-01-01 Online:1987-06-18 Published:1987-06-18
  • Contact: Fu Cheng-Xin

摘要:

 本文报道了我国黑龙江产桔梗科沙参属的10种1变种的染色体数目和核型,对其中
    7种作了减数分裂行为的观察。  其中6种1变种为首次报道,并发现2n=68的4x种。该
    属染色体基数多为17(x=17),但Adenophora trachelioides和A.remotiflora的基数为18
    (x=18),为该属独特基数。核型的共同特征是:小型,以中部(m)、近中部(sm)着丝点
    染色体为主,至少具一对近端着丝点染色体和一对随体染色体。该属染色体的演化处于二种
    水平:  数目变化(包括多倍化和非整倍体变化)和结构变异。  多倍化是该属物种形成的主要
    途径之一。结合其它性状讨论了这些种的分类,并确立1个四倍体新种(A. amurica)和1个
新组合(A.pereskiifolia ssp.alternifolia)。

关键词: 沙参属, 染色体数目, 核型, 黑龙江

Abstract:

This paper is a cytological part of biosystematic studies on Adenophora Fisch. in
Heilongjiang, China. Chromosomal numbers and karyotypes of 10 spp. and 1 var. are reported.
The results are summarized in Table 1.  The chromosomal numbers and karyotypes of 6 spp.
and 1 var. are first reported, including tetraploid species (2n=68) (A. pereskiifolia var. alterni-
folia, A. amurica and A. gmelinii).  The basic number of chromosomes in the genus is mainly
17 (x=17), but that of A. trachelioides and A. remotiflora (2n=36) is 18 (x=18), an unique
one in the genus.  The karyotypes of all the species examined are relatively uniform, which
means that they are derived from a common ancestral type.   The  chromosomes  are smaller,
varying between 2-4 μm.  The majority of chromosomes are m and sm ones.  And a pair
of sat-chromosomes and a pair of st chromosomes are always present.  The centromeric terminali-
zation value of chromosomes is 57.5-61.9%, showing higher symmetry of karyotypes in the
genus.  The karyotype of A. tetraphylla (2n=34) is the most symmetrical among these species.
Based on its morphological characters and distribution, the species may be considered as a re-
latively primitive member of the genus.
     The results show two revolutionary trends in karyotypes of the genus: number variation
(including polyploidy and aneuploidy) and structural variation.  The polyploidy is one of
the principal patterns of speciation in the genus. Combined with the other characters, these spe-
cies are taxonomically discussed, and two new taxa (A. amurica Fu et Liu and A. pereskiifolia
ssp. alternifolia (Fuh ex Y. Z. Zhao) Fu et Liu) are confirmed. A. trachelioides and A. re-
motiflora (both 2n=36) with obvious petioles seems more advanced than the other species (2n
34).

Key words: Adenopora, Chromosomal number, Karyotype, Heilongjiang