金冠鳞毛蕨复合体的三个新细胞型     

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   

法斗观音座莲——一个假定的属间杂交种     

秦仁昌  王中仁 《中国科学院研究生院学报》1982,20(3):347-350

  Angiopteris sparsisora Ching, sp. nov.      Species nova ab omnibus affinibus adhuc cognitis recedit rhizomate repente, dorsi- ventrali, habitu minore stipite tenui, levi, paleis  brunneis  lineari-lanceolatis  margine irregulariter fimbriatis peltati-fixis, pinnulis basi cuneatis vel late cuneatis, distincte breviterque petiolulatis, soris longitudine variis, inter se separatis a margine magis re- motis, paraphysibus rudimentalibus brevibus sparse praesentibus.      Tota planta 1—1.2 m alata, rhizomate repente, carnoso, cylindrico, dorsiventrali, 5— 6 cm diametro, radicoso, apice frondes 2—3 emittente, stipite 35—70 cm longo, 4—8 mm crasso, levi viridi, supra medium uni-geniculato (in frondibus pinnatis usque subbipin- natis), paleis brunneis lineari-lanceolatis basi rotunda peltati-fixis margine varie fimb- riatis sparse vestito; lamina stipite longiore, bipinnata aut subb ipinnata raro superne simpliciter pinnata; pinnis 2—3(—7)-jugis, ,alternis vel suboppositis, oblongis, 45— 55 cm longis, 18—23 cm latis, petiolo 4—16 cm longo suffultis, basi tumidis, pinnatis vel interdum simplicibus vel basi pinnatifidis; pinnulis plerumque 8—12-jugis, alternis vel suboppositis, patentibus, 8—18 cm longis, medio 1.5—3cm latis, lanceolatis, acuminatis, basin versus cuneatis vel late cuneatis, breviter petiolatis, pinnula terminali confomi paulo majore, petiolulata, hasi baud in alas decurrente, margine serrulatis; venis utrin- quo distinctis, patentibus, simplicibus vel furcatis, prope marginem curvatis; pagina frondis textura in sicco virescente, chartacea, rachi, costis, costulis venisque subtus sparsim minuteque paleaceis.  Soris breviter linearibus, 2—4 mm longis,  10—32-spo- rangiatis, inter se separatis, a margine 2—3 mm, remotis; paraphysibus sparsis brevibusrudimentalibus.  Sporis globulosis, suparficie dense tubuculatis.       Yunnan austro-orientalis:  Xichou Xian, Fadou, S. K. Wu 4203 (typus, PE), 4198, 8, October, 1962; ibidem, Z. R. Wang 566-1, 566-2, 566-3, 566-4, 566-5, 15, January, 1978; ibidem V. M. Chu 8212, 15, January, 1978. in valley under evergreen broad- leaved forests, alt. 1500—1550m.       In the tropical rain forest in southeastern Yunnan, China, the members of Angiopte- ris Hoffm. and Archangiopteris Christ et Gies. are often growing side by side in great abundance.  In January 1978 the second writer made a botantical trip there and col- lected in one locality ample herbarium material of an Angiopteris, which is identical with A. sparsisora Ching (ined.), based upon type specimens gathered by Mr. S. K. Wu from the same locality in 1962.  To our great surprise, however, this distinct taxon reveals a number of important morphological characteristics intermediate between An- giopteris and Archangiopteris as diagnosed above.       The present species resembles Archangiopteris in small build with creeping dorsi- ventral rhizome, unigeniculate, thin, smooth stipe in pinnate to bipinnatifid fronds, spa- ringly clad in linear-lanceolate peltately affixed scales with variously fimbriate margin, lamina 1—2 pinnate or subbipinnate, pinnules distinctly and shortly stipitate, base cuneate or broadly cuneate, sori of different length separated from each other by broad spaces, and rather far away (2—3 mm) from the margin, paraphyses few, rudimentary and short, but, on the other hand, it also similar to Angiopteris in usually bipinnate fronds, the petiole of pinnae with swollen base (blackish upon drying), short (2—4 mm long) linear sori consisting of 5—16 pairs of sporangia and globulax spores with densely tubucular sporoderms.  All the above characteristics combined clearly indicate the spe- cies is in all likelihood a natural hybrid between  Angiopteris  and Archangiopteris, pending cytological investigation and the reason for presently placing it in Angiopteris rather than in Archangiopteris is because of the fact that in overall impression the newtaxon appears more like the former than the latter.  相似文献   

蹄盖蕨科的亚科划分     

王中仁 《中国科学院研究生院学报》1997,35(1):32-36

 蹄盖蕨科的建立对蕨类植物的分类起了很大的推动作用，然而，即使按秦仁昌的狭义概念，它仍然是一个极其复杂的大科。自秦仁昌把该科划分为21个属以后，属级水平上的分类问题比较清楚了，但亚科、亚属和组的划分至今仍不成功。本文主要根据该科三个染色体基数X=42、41和40，结合孢子囊群着生的位置及其它形态特征，将其划分为3个亚科：冷蕨亚科、蹄盖蕨亚科和双盖蕨亚科。  相似文献   

教师要自我修德     

王中仁 《湖南教育》2001,(14):54-54

一是要树立正确的人生观。教师是以教育事业为己任，要堂堂正正做人，清清白白为师，踏踏实实做事，要格外重视个人品德修养，格外珍惜党和人民给予的施展才华、教书育人的机会，努力为教育多做贡献，为学生多传道、多授业、多解惑，把自己的理想、追求和事业融进广大学生之中，成为人民的好教师。否则，只为自己打算，只为自己奋斗，只为自己言乐，即使身在教师队伍，最终也会辜负党的培养、人民的重托。  相似文献   

横断山蹄盖蕨科新分类群     

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