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本文报道了中国苹果属Malus Mill．21种36类型的核型和6个多倍体类型的减数分裂联会构
型。 (木+多)(木+衣)海棠组Sect．Docyniopsis和花楸苹果组Sect．Sorbomalus中的滇池海棠系Ser．
Yunnanenses 属2A型，陇东海棠系Ser．Kansuenses中的变叶海棠M．toringoides和花叶海棠M．
transitoria属2A、2B则，三叶海棠系Ser．Sieboldianae属2B型，苹果组Sect．Malus中的苹果系
Ser．Pumilae和山荆子系Ser．Baccatae除小金海棠M．xiaojinensis 2B型外，均属3B型。减数分
裂观察结果有同源四倍体，节段异源三倍体和异源三倍体类型。本文还讨论了种类间在核型上的差异、栽培种的起源，核型的演化趋势以及无融合生殖类型的分类学处理。 相似文献
2.
本文报道浙江产菝葜属smilax 7个种的染色体数目和核型。S．nipponica有两种核型，2n＝
26和2n=32，均为3B型，但后一种细胞型的雄株的第一对染色体大小不等，可能为性染色体；S.
riparia 2n=30，属3B型；S．siebodii n＝16；S. china有两个染色体数目，2n＝96 和n＝15；
S. davidiana 2n=32，属3B型，对减数分裂MI的观察发现n＝16；S．glabra 2n=32，亦属3B
型：S. nervo-marginata var．liukiuensis 2n=32，属3C型。讨论了种间在核型上的差异、属的基数、
核型演化趋势和性染色体等问题。 相似文献
3.
In the work mitotic chromosomes in root-tips of 7 species native to Sichuan Pro-
vince were examined and their karyotypes were analysed based on 7-8 cells at mitotic meta-
phase, using Levan et al.'s (1964) nomenclature. The list of species and origin of the materials
used in this work are provided in the appendix. The micrographs of mitotic metaphase of all
the materials are shown in Plates 1 and 2; the idiograms in Fig. 1, 1-9, and the parameters
of chromosomes are provided in Tables 1-9. All the chromosome countings and karyotypes in
this paper are reported for the first time.
Characteristics of the karyotypes may be summarized as follows:
1. 2n=38 are found in all the materials except A. sichuanensis, which has 3 cytotypes, i.e,
2n=38+5B, 2n=38+lB and 2n=38+OB (Plate 2, 1-2, Fig. 1, 5-6).
2. The karyotypes are of two major types: the karyotype of A. flaviflora falls into 3C in
Stebbins's (1958, 197l) classification of karyotypes and those of all the other species into 2C.
The two types are also different from each other in the number of large and medium-sized
chromosomes pairs and morphology of the first pair of chromosomes (compare Plate 2, 5, Fig.
1, 9 with the other micrographs and idiograms).A. flaviflora with the karyotype 3C also differs
from the other species in a series of gross morphological characters: the species is of a yellow and
campanulate corolla.
3. The species with caespitose leaves (A. caespitosa and A. omeiensis) have essentially the
same karyotype, which is rather different from those of the species with scattered leaves. There
are two pairs of small sm chromosomes (arm ratio ≥1.90) in the former karyotype (Tables 1
and 3), but all the small chromosomes are m or sm with arm ratio <1.80 in the latter karyotypes. 相似文献
4.
本文对安徽南部贝母属的5种植物的核型进行了研究，结果如下：祁门贝母Fritillaria qimenensis
D C.Zhang et J．Z．Shao：2n=24+4Bs=3m+lsm+8st(2sc)+12t(2sc)+4Bs。铜陵黄花贝母F．monantha
Miq．var．tonglingensis S．C.Chen et S．Ｆ．Yin本文报道2个细胞型，细胞型I：2n=24+5Bs=4m+8st
(2sc)+12t(2sc)+5Bs；细胞型II：2n=24=2m+2sm+8st(2sc)+12t(2sc)。窄叶小贝母F.xiaobeimu Y．K．
Yang，J．Ｚ．Shao et M．M．Fang：2n=24=2m+2sm+10st(4sc)+lot。宁国贝母F．ningguoensis S．C.
Chen et S．F．Yin：2n=24=2m+2sm+8st(2sc)+12t。浙贝母F.thunbergii Mig．：2n=24=2m+2sm+8st(2sc)+12t(2sc)。除浙贝母外，其余均是近年发表的新种或新变种，其染色体数目和核型均为首次报道。 相似文献
5.
本文对浙江产的Disporum sessile， Tricyrtis macropodo， Scilla rcilloides，Ophiopogon japoni-
cus,Liriope platyphylla和Allium macrostemon的核型作了分析，并报道了Polygonatum odoratum
和Asparagus cochinchinensis 的单倍体染色体数目。其中绝大多数为国产材料的首次记载。 相似文献
6.
本文对陕西、四川和河北的Paris 2种，Cardiocrinum giganteum, Smilacina 2种，Allium
2种， Asparagus 2种，以及Convallaria majalis 的核型作了分析，其中Paris polyphylla var.
latifolia， Smilacina henryi 和 Allium ovalifolium 的染色体报道为第一次。 首次发现Perisverticillata 中四倍体细胞宗的存在。本文对Paris的核型、地理分布和分类作了分析讨论。 相似文献
7.
王中仁 《中国科学院研究生院学报》1985,23(5):344-351
Two new species and one nataral hydrid close to Dryopteris chrysocoma
(Christ) C. Chr. are found by means of cytological study, which shows that D. chrysoco-
ma circumscribed in the past is not a single diploid in its range, but consists of seve-
ral cytotypes.
D. para-chrysocoma is a sexual diploid with narrowly lanceolate laminae that are
almost glandless. The scales on the rachis and pinna rachis are pale brown, longer in
length (4-7 mm) and denser. Indusium lacks glands too. The ultimate segments are
narrower and separated by arrow spaces. These characters distinguish it from D. chry-
socoma.
D. zinongii is a sexual tetraploid. It is recognised by its ovate laminae, sparse,
small and dark brown scales on the rachis and pinna rachis (1-2mm in length),
broad segments closely adjacent one another and membranous indusia.
D. × daliensis is shown to be an apomictic triploid which has rather irregular meio-
sis. There are some free chromosomes at the first metaphase, some lagging chromoso-
mes and bridges at the first anaphase and some micronuclei in young spores. Some un-
paired univalents can even be seen at diplotene. Approximately 14 univalents, 14 bi-
valents and 27 trivalents were observed at late diakinesis. Although a large number of
SMCs were counted, a definite chromosome number has so far proved impossible to be
obtained. This is possibly caused by variable pairing of the three genomes and diffe-
rent trivalent numbers formed in each SMC. As a result, generally less than 64 abor-
tive spores are formed in each sporangium, but the sporangium with 32 spores could
also be found rarely. All these show that this hybrid may be derived from the cross be-
tween a diploid and a tetraploid which have homoeologous genomes.
D. × daliensis is morphologically intermediate between D. zinongii and D. para-
Chrysocoma. in respect to characters such as ovate-lanceolate laminae, brown rachis sca-
les with a dark central stripe, 2-3 mm in length, and abortive spores in unequal size
and different shapes etc. In addition, they are often found growing together in Cang
Shan, Yunnan. It is therefore reasonable to consider that the latter two are probably
the parents of the former.
These new cytotypes show the presence of Dryopteris chry-socoma complex which
is generally characterized by shell-shaped indusia and glandular fronds. Accoding to
the morphology, D. woodsiisora Hayata, D. tenuissima Tagawa, D. alpicola Ching et Z.
R. Wang, D. fangii Ching, Fraser-Jenkins et Z. R. Wang and D. pseudochrysocoma
Ching etc. should be the members of this complex. In order to clarify the relation-
ships between all the members of D. chrysocoma complex, a great deal of further cy-
togenetic study, including artificial hybridization and analysis of meiosis in both wild
and synthesized hybrids, is required.
The author is grateful to Prof. R. C. Ching and Mr. C. R. Fraser-Jenkins of the
British Museum (Natural History) for their kind and helpful suggestion, and thank
Mr. Q. Xia and Mr. Y. L. Ma for their help in the field work. 相似文献
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9.
本文首次报道和分析了阿魏属Ferula L.分布区东缘3个种的染色体数目和核型。 太行阿魏F.
licentiana Hand.-Mazz．的核型公式为2n=22=14m+2sm+6st(2sat)，铜山阿魏F．licentianc
Hand．-Mazz．var．tunshanica(Su)Shan et Q．X．Liu的核型公式为2n=22=14m+8st(2sat)，
硬阿魏F．bungeana Kitag．的核型公式为2n=22=12m+6sm+2st。 它们的核型都属2A型．在此基
础上从染色体角度进一步论证了铜山阿魏作为太行阿魏的变种和硬阿魏从近前胡亚属 Subgen.
Peucedanoides(Boiss.)Korov．中分出的合理性．根据已有资料，提出该属的染色体基数为X=11,
基本核型公式为2n=22=14m+4sm+4st。 本属核型对称性偏高，核型变异性偏小，与该属的自然性和稳
定性以及该属的分类地位的合理性和可靠性相吻合。 本文还分析了国产阿魏属内各种类的核型，进化程度，并对它们进行了细胞分类处理，对于出现与经典分类不一致的原因进行了讨论。 相似文献
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