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1.
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
2.
陆树刚 《中国科学院研究生院学报》1993,31(4):385-391
本文研究云南产鳞毛蕨属植物的属下分类并列出所有的种类。该属植物在云南现知至少有88种，属下可划分为3个亚属和12个组。为了使这些类群之间的特征轮廓清晰，本文提供了分亚属及分组的检索表。 相似文献
3.
4.
The present paper is the Supplement 2 to the Flora of Xizang, based upon
a collection in 1980 by Mr. W. L. Chen et al. from Mêdog, the south-eastern part of
Xizang. In the paper 11 new species are desribed and 10 new-record species are repor-
ted. All the type specimens are kept in the Herbarium of the Institure of Botany,
Academia Sinica (PE). 相似文献
5.
陆树刚 《中国科学院研究生院学报》1990,28(6):471-476
本文修订了鳞毛蕨属泡鳞亚属的特征范围，对该亚属的2个组12个种进行了分类研
究，发现其中有新种1个，云南新分布的种5个。本文还对长期混淆不清的Dryopteris labo-rdei与D．gymnosora 的分类特征还进行了清理，恢复前者为独立存在的种。 相似文献
6.
钱家驹 《中国科学院研究生院学报》1984,22(3):227-230
This paper deals with some species of Lunathyrium Koidz. in N. E. Asia;
including the eastern mountainous district of N. E. China; Far East Region of U. S. S. R.; Korea and Japan. 相似文献
7.
eterachopsis was proposed by the senior author as an independent genus of
the family Aspleniaceae in 1940 with 2 species. Since then much study on its morpho-
logy, anatomy, gametophyte and palynology has been carried out by Nayar, Bir, Chan-
dra & Nayar and Chang et al., and they are of the opinion that the genus like Ceterach,
is a comparatively primitive element in the family Aspleniaceae. The queer zigzag pa-
tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae,
and also suggests its antiquity in evolution. So far only 3 species (C. dalhousiae, C.
paucivenosa and C. magnifica) are recognized, the former from W. Himalayas, also
known from Africa, while the latter two from W. S. China (Yunnan). However, in
the past forty years the Chinese botanists have discovered 2 more species as new in N.
W. Yunnan, thus bringing the total known species of the genus up to 5. The present
paper is a brief summary on the genus Ceterachopsis, which will be published in detail
in the Flora Sinica vol. 4.
Pteridologists are also divided in their views regarding the generic status of Cete-
rachopsis with 5 well-defined species in Yunnan and the East Himalayas. We prefer
to mintain it as a genus separate from Asplenium on account of its distinct morpholo-
gical features. It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way. 相似文献
8.
One new species of the genus Mecodium, M. paramnioides H. G.Zhou et W. M. Chu, is described from Guangxi, China. 相似文献
9.
王中仁 《中国科学院研究生院学报》1994,32(1):82-92
Nine new species and twelve new varieties of Athyriaceae from the Hengduan
Mountains, China, are described. 相似文献
10.
发现滇桂三相蕨Ataxipteris dianguiensis W. M. Chu & H. G. Zhou和多形叉蕨Tecataria polymorpha (Wall. ex Hook.) Copel.为海南新分布, 并为滇桂三相蕨指定了后选模式，讨论了燕尾叉蕨T. simonsii (Baker) Ching和中型叉蕨T. media Ching的异同，澄清了三叉蕨T. subtriphylla (Hook. & Arn.) Copel.和多形叉蕨的形态变异，把云南产狭基叉蕨T. polymorpha var. subcuneata Ching & Chu H. Wang处理为多形叉蕨的异名。至此，海南产叉蕨科植物为8属20种。 相似文献