作 者 ：Li Lin-chu
期 刊 ：植物分类学报 1993年 5期
Keywords:Larix potaninii, Larix,
Abstract:
The present paper reports the karyotype of Larix potaninii Batal.
endemic to China, and discuss classification of Larix and its systematic position in
the Pinaceae based on karyotype and other data. The karyotypic formula of the
species is K(2n)=24= 12m+ 8sm+4st, which belongs to Stebbins’2A type and
the chromosome complement of relative length is 2n=24=4L+8M2+8M1+4S.
The karyotype of the genus Larix (10 species) is composed of six pairs of longer
metacentric chromosomes and six pairs of shorter submetacentric or subtelocentric
chromosomes with arm ratio>2. This karyotype is an advanced one. It seems
that Sect. Multiserales is more advanced than Sect. Larix. On the basis of the
comparison among the karyotypes of pinaceous genera, the author finds that
Larix and Pseudotsuga are much more closely related to each other than any of
them to the others. Therefore, it may be more appropriate to group these two
genera into Subfamily Laricoideae, which is a more advanced one. The conclusion
is also supported by the data from morphology, anatomy, palynology,
biochemistry, palaeobotany and so on.