作 者 ：Liang Guo-Lu, Lin Meng-Jia, Chen Jia-Yu, Liu Jun-Su
期 刊 ：植物分类学报 1992年 6期
Keywords:Tea,
Abstract:
Nine forms of Camellia sinensis (L) Kuntze from Guizhou, Yunnan,
Sichuan and Fujian Provinces were cytotaxonomically studied in this work. The
wall degradation hypotonic method was used for preparing chromosome samples
which were stained in Giemsa. The micrographs of their somatic metaphase
are shown in Plates 1-2, the ranges of chromosome relative lengths, arm ratios,
karyotype formulae and classification of karyotypes according to Li and
Chen (1985) are shown in Table 1 and the idiograms in Fig. l. The main points
are mentioned as follows:
(1) All these forms are found to be diploid with 2n = 30, and they are reported
for the first time except Yunnan(Fengqing)cultivated form.
(2) All the karyotypes of the forms examined are relatively uniform, which re-
veal the gradual decrease in size from the longest to the shortest chromosomes,
similar chromosomal relative length, smaller chromosome types varying between
2- 5μm. The karyotype mainly consists of metacentric (m) and submeta-
centric (sm) chromosomes. Sat-chromosomes are difficult to be discovered
on mid -metaphase chromosomes. The cytological information confirms the close
relationship among these tea forms.
(3) According to the asymmetry of karyotype, the nine tea forms are divided
into two types: one consists of the arbor with macrophyll, i.e. Guizhou and
Yunnan( Fengqing and Tengchong)cultivated forms, which have the”2A”
karyotype possessing metacentric(m) and submetacentric(sm) chromosomes. The
karyotypes might be of the most symmetrical or primitive type ;the other consists of
the bush or microarbor with mostly medium- and microphyll, less frequently
macrophyll, i.e. Qianmei 419, Qianmei 502, Yaan,Fuding, Sichuan and Qianmei
101 cultivated forms, which have the “2A” and “2B” karyotypes, consisting of
metacentric (m), submetacentric (sm) and a pair of subtelocentric (st)
chromosomes, and more asymmetrical than that of the first karyotype. They
might be more advanced.
(4) In recent years, two subspecies, i.e. ssp. “yunnan”and ssp. “bohea”,
including seven varieties, in C. sinensis were recognized but not formally published
by Zhuang et al. (1981). From the present work and the previous reports the au-
thors agree with Zhuang’s classification, because recognition of two subspecies is re-
markably consistent with the two kinds of karyotypes reported here. C.sinensis ssp.
“yunnan” with arbor and macrophyll characters has more symmetrical karyotype
than that of C. sinensis ssp. “bohea” with bush or microarbor and mostly medium-
and microphyll characters. That is to say, ssp.”yunnan” is more primitive than
ssp. “bohea”.
(5) Based on the karyotype analysis of arbor and macrophyll teas reported
before and here (see Table 3), the authors support the viewpoint that Yunnan-
Gui zhou Plateau is the original center of tea Plants, whereas Assam form in In-
dia is derived.