作 者 ：Wang Jin-Wu, Li Mao-Xue, Yang Ji
期 刊 ：植物分类学报 1991年 6期
Keywords:P. cyrtoncma, Variation, Evolution,
Abstract:
The present paper is a report on combined cytological and taxonomical studies
of Polygonatum odoratum and P. cyrtonema. Based on the extensive field observation and
mass collection for some years, the authors made a detailed comparison of the variation pat-
tern of morphology、cytology as well as geographic distribution between forms
of P. odoratum and P. cyrtonema. The results show that: Form I: Stem angular, leaves
elliptic, peduncles with one, rarely two flowers, perianth 1.7-2.0 cm long, stamens adnate to
perianth in the middle part or a little lower. The karyotype formula is 2n=20=12m+8sm
(2SAT); Form II: Stem angular, leaves narrow-oblong, peduncles with 2-3 flowers,
perianth 2.8-3.2 cm long, the position of stamens on perianth is above the middle part.
It has the karyotype 2n=20=8m+1osm(4SAT)+2st; Form III: Stem terete, leaves
oblong-lanceolate, peduncles with 3- 10 flowers, perianth 1.5- 2.0cmlong, stamens are
adnate to perianth also above the middle part. In this form, two kinds of karyotypes are
found: 2n = 22 = 6m+8sm+8st and 2n = 20 = 4m+6sm (2SAT) +10st; Form IV: Stem terete,
leaves elliptic, peduncles with 1-4 flowers, perianth 2.3-2.8 cmlong, stamens adnate to
perianth above the middle part. The karyotype formulae are 2n = 20 = 4m+14sm (2SAT)+2st
and 2n = 20 = 10m+10sm (2SAT); Form V: Stem terete, leaves oblong-lanceolate, peduncles
with 3-5 flowers, perianth less than 2.0cm long, stamens adnate to perianth above the mid-
dle part. It is of the karyotype 2n=22=4m+8sm(2SAT) +10st. It is pointed out that
the P. odoratum collected from the Qinling Range may be a hybrid or an intermediate in the
evolutionary process from P. odoratum to P. cyrtonema. The differences between the differ-
ent forms of P. cyrtonema are obvious and stable, and are probably derived from the
chromosomal variation. The different forms of P. cyrtonema may have evolved
from P. odoratum along different courses.