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王中仁 《中国科学院研究生院学报》1989,27(6):421-438
本文报道了中国产10种凤尾蕨属植物和2种蕨属和栗蕨属植物的细胞学研究结果。 在凤尾蕨
属中,8种是多倍体或具有多倍体细胞型,4种是无性孢子繁殖的后代,6种实际上是种复合体或种复合
体成员,单纯有性生殖的二倍体只有2种。凤尾蕨至少具有9条孢子发生路线,在其同一个体上除了产
生二倍孢子外,还可能产生少量加倍或多倍孢子;广义的蜈蚣草实际上是个种复合体,其祖先的二倍体
细胞型广泛分布于中国亚热带地区说明这里可能是该复合体的起源中心;岩凤尾蕨具有不寻常的染色 体数目n=55,这说明在本属和本科中可能存在着非整倍体进化。 相似文献
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王中仁 《中国科学院研究生院学报》1983,21(1):102-104
The spores of all specimens of Cystopteris in the Herbarium of the Institute of
Botany, Academea Sinica have been examined under light microscope. The result of
the survey shows for the first time that the distribution of Cystopteris dickieana Sim
with non-spiny spores is also quite wide-spread in China, including provinces Xinjiang,
Xizang, Qinghai, Gansu, Sichuan, Hebei in northwestern China and Tibetan plateau.
The range of altitude for this species varies from 1800 to 5400(5600) m, but C. fragilis
(L.) Bernh. from 210 to 4600 m. The differences in the altitudinal distribution range
seem to suggest that C. dickieana is more tolerant of cold conditions than C. fragilis.
There are also variations in size and ornamentation of the spores in each of the two
species. Their ploidy and relationships await futher cytogenetical study from livingmaterials. 相似文献
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王中仁 《中学物理教学参考》2012,(4):28+55
"幸福"是一个极富诱惑力的美丽词汇,它是人生的理想状态,也是人类追求的目标.费尔巴哈说:一切健全的追求都是对于幸福的追求.幸福是一种追求,是一种向往,是一种主观的心理体验.追求幸福是人的本性.作为教师,有着特殊职业的社会角色,还应有自己的职业幸福.这种幸福是教师在教育教学活动中和育人成功后获得的一种愉悦的情感体验.对于教师,只有在工作中充溢着幸福感,心情愉 相似文献
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综合运用孢粉学、细胞学、生态学和形态学的证据,处理了中国产铁角蕨Asplenium trichomanes L.
的种下分类问题,将其划分为4个亚种和1个变种:原亚种A.trichomanes L.ssp.trichomanes,喜钙亚种
A.trichomanes L. ssp.inexpectans Lovis,四倍亚种A.trichomanes L.ssp. quadrivalens D.E.Meyer emend.
Lovis,粗轴亚种A.trichomanes L.ssp.pachyrachis(Christ)Lovis et Reichst.和哈如变种A.trichomanes L.
var.harovii Moore emend.Midle,并提供了它们在中国的分布情况。查阅研究中国科学院植物研究所
(PE)的标本时发现,一些定名为A.trichomanes L.var.centrochinense Christ(华中变种)的模式标本碎片在形态上和倍性上均不同于已知分类群,认为应给予其新种的分类地位。 相似文献
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The fern Athyrium crenulato-serrulatum Makino is found in the whole of
Northeastern Asia embracing Northeastern China, Korea, Japan, Ussuri and the Far
East USSR. It is similar to the European Athyrium distentifolium, formerly known
as A. alpestre, in having exindusiate round or ovate sori, but differs in several
essential characters, such as the well-spaced fronds are biseriately arranged along a
thick and long-creeping rhizome, the base of stipe is thickened and not attenuated to-
wards the point of attachment, the deltoid-ovate lamina with the basal pinnae as long
as those next above, which all are distinctly petiolate and the rachis, costis and espe-
cially the costules of pinnules clad in fine pale-colored generally septate hairs under-
neath. All these clearly show that the fern in question is not an Athyrium sen. str.
neither Pseudoathyrium Newman to which latter the fern was referred by Nakai.
However, we have been long suspicious of its proper systematic position. In his recent
monograph on the genus Cornopteris (Acta Phytotax. Geobot. 30: 104. 1979.) Kato
has pointed out that C.crenulato-serrulata (Makino) Nakai “has the northernmost
destribution in the genus and exhibits a few characteristics similar to Athyrium, the
swollen base of stipes with projections and cartilaginous lamina margin. By these
characteristics the species is clearly discriminated from other species”. According to
Kurita (1964), Mitui (1970) and Karo (1978) the species in question has chromosome
numbers n=40, the base number of the subfamily Athyrioides instead of x=41, the
base number of the subfamily Diplazioides including Cornopteris Nakai. Since thefern in question fits no other athyrid genera, hence a new genus is proposed. 相似文献
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王中仁 《中国科学院研究生院学报》1997,35(4):317-340
已发表的涉及中国的蹄盖蕨属植物的名称有300多个,它们初步被处理为117种和一些变种和杂种,全文将分4次报道,本篇是第一部分:分种检索表。 相似文献
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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