A Classification Synopsis of the Genus Dryopteris from Yunnan

The genus Dryopteris of the Dryopteridaceae is one of the largest genera in pteridophytes, which contains about 300 species and is distributed throughout the world. There are about 200 species of this genus in China, of which at least 88 are present in Yunnan. In this paper, the author presents a classification synopsis of the genus Dryopteris. Subg. I Pycnopteris (T. Moore )Ching 1 species Subg. II. Dryopteris Sect. 1. Hirtipedes Fraser-Jenkins 19 species Sect. 2. Pandae Fraser-Jenkins 1 species Sect. 3. Fibrillosae Ching 18 species Sect. 4. Chrysocomae S. G. Lu 7 species Sect. 5. Caespitosae S.G.Lu 5 species Sect. 6. Pallidae Fraser- Jenkins 10 species Sect. 7. Marginatae Fraser-Jenkins 7 species Sect. 8. Splendentes Fraser- Jenkins 2 species Sect. 9. Purpurascentes Fraser- Jenkins 1 species Sect. 10. Nephrocystis H. I tô 3 species Subg. llI. Erythrovariae (H. I tô ) Fraser-Jenkins, emend. S.G. Lu Sect. 11. Erythrovariae 11 species Sect. 12. Variae Fraser- Jenkins 3 species A key to these groups is given and all the species are enumerated in the pres- ent paper.     

中国鳞毛蕨属泡鳞亚属的分类研究

鳞毛蕨属ＤｒｙｏｐｔｅｒｉｓＡｄａｎｓ．泡鳞亚属ＳｕｂｇｅｎｕｓＥｒｙｔｈｒｏｖａｒｉａｅ（Ｈ．Ｉｔｏ）Ｆｒａｓｅｒ－ＪｅｎｋｉｎｓｉｎＢｕｌ．Ｂｒ．Ｍｕｓ．Ｎａｔ．Ｈｉｓｔ．Ｂｏｔ．１４（３）：１９５．１９８６．Ｔｙｐｅ：Ｄｒｙｏｐｔｅｒｉｓｅｒｙ...     

Diploid and triploid offspring of triploid agamosporous fernDryopteris pacifica

A cytological and reproductive study of the diploid and triploid agamosporousDryopteris pacifica was made to elucidate the origin of its infraspecific cytotypes. Some triploids produced 16 spore mother cells (SMCs) sometimes with n=41II+41I chromosomes, in addition to eight SMCs with n=123II, in each sporangium. In the former case the 16 SMCs usually underwent abnormal meiosis to give rise to some 50 spores, some of which were regular-shaped; in the latter the eight SMCs multiplied into 32 spores by normal meiosis. We found that spores from one of the triploid plants developed into either diploid or triploid gametophytes, which further apogamously produced diploid or triploid sporophytes, respectively. This novel mechanism of ploidy reduction is discussed in relation to the origin of diploid agamosporous ferns, the taxonomic complexity of the species, and the correlation of agamospory with polyploidy. The mechanism is also compared to that operating in agamospermous angiosperms.     

Cytological Observations on Some Species of Dryopteris and Polystichum from China

Cytological observations on five Dryopteris species and four Polystichum species from China are reported. Most of the materials examined were field-fixed in Emei Shan, Sichuan province, and one of them was in Dali Xian, Yunnan province. Only the count of Dryopteris goeringiana was made from the plant brought from Wuling Shan, Beijing and grown in the garden of our Institute. All the materials were fixed in 1:3 acitic acidalcohol, and stained with acetocamine. All the counts were made at diakinesis or metaphase I of meiosis in SMCs .The results of the observation on them are summarized in table 1. Of these, the chromosome numbers for six species are first report. Five species are sexual: diploid: D. goeringiana, D. porosa, D. subinaequalis, D. yui and P. stenoghyllum. Three spe cies are sexual tetraploid: P. acutidens, P. erosum and P. moupingense. Only D. juxtaposita is an apomictic triploid. The vouchers are preserved in the Herbarium of our Institute (PE). We are indebted to Prof. R. C. Ching and C. R. Fraser-Jenkins for identification of the materials.     

Effect of storage method on spore viability in five globally threatened fern species

Spore germination of five globally threatened fern species [Culcita macrocarpa C. Presl, Dryopteris aemula (Aiton) O. Kuntze, D. corleyi Fraser-Jenkins, D. guanchica Gibby and Jermy and Woodwardia radicans (L.) Sm.] was determined after 1, 6 or 12 months of storage in glass vials (dry storage) or on agar (wet storage) at -20, 5 or 20 degrees C. In all species, storage technique, storage temperature and the technique-temperature interaction all had a significant effect on germination percentage. In most cases, the germination percentage was best maintained by wet storage at 5 or 20 degrees C. In the case of the hygrophilous species C. macrocarpa and W. radicans, 6 or 12 months' dry storage killed most spores. Only Woodwardia radicans germinated in the dark during wet storage at 20 degrees C. Wet storage at 5 degrees C prevented dark germination, and reduced bacterial and fungal contamination. Wet storage at -20 degrees C killed all or most spores in all species. In the three Dryopteris species, the differences among the storage conditions tested were smaller than in C. macrocarpa and W. radicans, and the decline in spore viability during storage was less marked, with high germination percentages being observed after 12 months of dry storage at all three temperatures. Dry storage, which has lower preparation time and space requirements than wet storage, was generally more effective at the lower temperatures (-20 or 5 degrees C).     

红盖鳞毛蕨孢子囊早期发育与质体分化的研究

利用光学显微镜和透射电子显微镜观察了红盖鳞毛蕨(Dryopteris erythrosora(Eaton)O.Ktze.)孢子囊的发育及在此期间质体的分化过程。研究表明:(1)红盖鳞毛蕨孢子囊的发育类型属于薄囊蕨型;(2)绒毡层为混合型,即内层绒毡层为原生质团型,外层绒毡层为腺质型;(3)孢子囊原始细胞中的质体通过3条路径分化,其一,原始细胞中含淀粉粒的质体通过分裂分配到下方细胞,继而进入孢子囊柄;其二,原始细胞分裂产生的新生质体被分配到上方细胞,进而被分配到除顶细胞外的原基细胞中,顶细胞将含淀粉粒的质体通过分裂分配到外套层原始细胞中;其三,顶细胞也将具淀粉粒的质体通过分裂分配到内部细胞,使分裂产生的孢原细胞和绒毡层原始细胞具新生质体;造孢细胞和孢子母细胞的质体具淀粉粒,孢子母细胞还具油体,新生孢子中具造粉体和油体;两层绒毡层具新生质体,随着退化外层绒毡层出现造粉体,内层绒毡层出现油体;(4)红盖鳞毛蕨与少数被子植物小孢子发育阶段质体分化模式类似,由前质体分化为造粉体再到油体。研究结果为蕨类植物质体在孢子囊发育过程不同组织细胞中的差异分化提供了新观察资料,为蕨类植物发育生物学和系统演化研究提供科学依据。     

A Taxonomical Study of the Family Aspidiaceae from the Mainland of Asia

The object of this paper is to deal with the taxonomical problems of the family Aspidiaceae from the mainland of Asia. In recent years I have had the opportunity to study copious materials of the family from this region, and recognized the following nine genera, namely, Lastreopsis Ching, Ctenitis C. Chr., Ctenitopsis Ching, Pleocnemia Presl, Arcypteris Underw., Tectaria Cavanilles, Quercifilix Cop., Hemigramma Christ and Pteridrys C. Chr. et Ching. The members of this family are middle-sized, terrestrial ferns; rhizome erect or suberect, dictyostelic, scaly; leaves tufted, generally uniform, simple pinnate to tripinnatifid; veins free or anastomosing, forming areoles with or without free included veinlets; rachis and costa raised on the upper surface, and, as a rule, covered with pale brown multicellular articulate hairs (ctenitis-hairs); sori round or in a few cases acrostichoid; indusia reniform, or in some genera absent; spores bilateral with perispore. Dryopteridaceae and Lomariopsidaceae are closely related to Aspidiaceae, and both were placed in the latter family by the fern students in the past. The main differences of Dryopteridaceae from Aspidiaceae are: leaves pale green when dried; costa and costule grooved and free from articulate hairs (ctenitis-hairs) on the upper side; veins free or very rarely anastomosing (venatio cyrtomii). In general appearance the genus Ctenitis of Aspidiaceae is very similar to the bipinnate species of Dryopteridaceae, such as Dryopteris filix-mas (Linn.) Schott, but its costa and costule are raised and covered by ctenitis-hairs on the upper side, and the leaves turning dull brown when dried, so that it has no difficulty in distinguishing the genus from the true Dryopteris. The recognition of the free-veined Ctenitis and its allies as the primitive tectarioid ferns is very important in delimiting both Aspidiaceae and Dryopteridaceae, which were all mixed up in the past. Moreover, from the standpoint of plant geography, these two families are also distinct, for the Dryopteridaceae are mainly ferns of the temperate regions and the mountains in subtropics in the Northern Hemisphere, but the Aspidiaceae are pantropical by origin. The chief differences of Lomariopsidaceae from the Aspidiaceae are: rhizome creeping or high-climbing; leaves strongly dimorphous, free from the ctenitis-hairs; sori acrostichoid. That Holttum has made Aspidiaceae a subfamily Tectarioideae of the family Dennstaedtiaceae proves to be very unnatural, because there is hardly any affinity between the two families; while Aspidiaceae of Copeland is a terrible mixture of Thelypteridaceae, Athyriaceae, Dryopteridaceae and Aspidiaceae (sen. strict.) and a few other families, for even he himself admitted that no one can use the definition to identify any unknown members of his family. Finally, I feel grateful to my teacher, Professor R. C. Ching, for his constant encouragement and warm guidance received both in the course of my study and in the prepara-tion of the present paper.     

A Taxonomic Study on the Genus Dryopteris Subgenus Erythrovariae (H. Ito) Fraser-Jenkins from Yunnan

In the present paper, the circum cription of the genus Dryopteris subgenus Erythrovariae (H. Ito) Fraser-Jenkins is revised, and a taxonomic study on the subgenus from Yunnan Province is carried out .The subgenus contains 2 sections, 12 species in Yunnan, of which D. yongdeensis W. M. Chu is a new species, D. championii, D. erythrosora, D. gymnosora, D. indusiata and D. integriloba are first recorded from Yunnan. The confusion between Dryopteris labordei and D. gymnosora is clarified, the former being treated as an independentspecies.     

Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum,Pteridaceae)

We investigated the different processes involved in spore liberation in the polypod fern Adiantum peruvianum (Pteridaceae). Sporangia are being produced on the undersides of so-called false indusia, which are situated at the abaxial surface of the pinnule margins, and become exposed by a desiccation-induced movement of these pinnule flaps. The complex folding kinematics and functional morphology of false indusia are being described, and we discuss scenarios of movement initiation and passive hydraulic actuation of these structures. High-speed cinematography allowed for analyses of fast sporangium motion and for tracking ejected spores. Separation and liberation of spores from the sporangia are induced by relaxation of the annulus (the ‘throwing arm’ of the sporangium catapult) and conservation of momentum generated during this process, which leads to sporangium bouncing. The ultra-lightweight spores travel through air with a maximum velocity of ~5 m s^-1, and a launch acceleration of ~6300g is measured. In some cases, the whole sporangium, or parts of it, together with contained spores break away from the false indusium and are shed as a whole. Also, spores can stick together and form spore clumps. Both findings are discussed in the context of wind dispersal.     

Morphological and chromosomal variation of the Dryopteris varia (L.) Kuntze complex (Dryopteridaceae) in Korea

The Dryopteris varia complex is highly variable in morphology, resulting in taxonomic confusion in delimiting taxon boundaries and determining relationships. We have examined the variation in morphology, chromosome number and mode of reproduction of the Korean members of the D. varia complex to clarify their taxonomic identities. Landmark analysis of the leaf blades and pinnae and the principal components analysis of 31 morphological characters revealed seven entities within the D. varia complex in Korea; these comprise D. varia s. str., D. pacifica, D. sacrosancta, D. bissetiana, D. saxifraga, D. saxifragivaria, and the Suak population which is considered to be a new taxon. Mitotic chromosome counts and examination of reproduction modes indicated that D. bissetiana in Korea appears to be agamosporous with diploid (2n = 82) or triploid (2n = 123) chromosome numbers. However, D. saxifraga is sexual diploid or agamosporous triploid, and the other taxa are agamosporous triploid. Dryopteris bissetiana, D. saxifraga and D. saxifragivaria are similar in major morphological characteristics, but show differences in attachment and shape of rachis scales. The results also suggest that agamosporous triploid D. saxifragivaria was probably derived from hybridization between sexual diploid D. saxifraga and D. bissetiana.     

A Preliminary Study on Cytology of Chinese Pteris

Cytological and biosystematic studies on the genus Pteris have made a great contribution to the theory of speciation and evolution in ferns. Sino-Japanese area is one of the speciation centers of this genus. But only a few Chinese species have been known cytologically. As a preliminary study, ten species of the genus Pteris and two species of the related genera Pteridium and Histiopteris were observed. All the materials were collected from southwest and south China. Their young sori were fixed in ethanol and glacial acetic acid (3:1), in the field. The preparations were made with acetocarmine squash method. The vouchers are deposited in PE. The results of observation are summarized in Table 1. Of Pteris, four species are agamosporous, eight are polyploid, six are actually the members of species complexes. Only two species are purely sexual diploids. Pteris cretica L. var. nervosa (Thunb.) Ching et S. H. Wu has 58 autobivalents at meiosis of spore mother cell, and usually produces 32 diplospores per sporangium. It is obviously an agamosporous diploid. Apart from 32-spored sporangium, some 4-, 8-, 16-, 64-, 13-, 34-, 36-spored, completely abortive or partly abortive sporangia were also found in the fixed material of a single individual. For explaining these unusual types of sporangia at least nine sporogenesis routes can be inferred. It may not be impossible that besides mainly producing functional diplospores, P. cretica var. nervosa also gives a few functional giant spores with a doubled or multiplied somatic chromosome number, which means that polyploids may be simply derived from the spores produced by their diploid parent. The spores in a sporangium are usually tetrahedral, but a few bilateral ones are also found in some sporangia. Sometimes, the bilateral spores are even more than the tetrahedral ones in a sporangium. Pteris vittata L. from the type locality shows 58 bivalents at diakinesis of meiosis. Without doubt, it is a sexual tetraploid, which was also found in south Guangdong and south Yunnan. However, Its natural ancestral diploid has been widely found in the subtropical regions of China, such as Sichuan, Guizhou, Yunnan and Hubei provinces. A sterile triploid with the chromosome number of n=201Ⅰ+26Ⅱ+5Ⅲ and a sterile tetraploid hybrid with the chromosome number of n=9Ⅰ+45Ⅱ+3Ⅲ+21Ⅴ were found in south Yunnan and south Guangdong respec tively. It is evident that P. vittata L. sensu lato is a species complex which includes several cy totypes. Its hexaploid form was reported from south India by Abraham et al. The distribu tion pattern of different cytotypes in P. vittata complex may indicate that the tropics is more favourable to formation and surviving of polyploid than the subtropics. However, it is most possible that Chinese subtropics is the origin place of the ancestral member in the P. vittata complex. In gross morphology, the tetraploid and triploid forms are only bigger and stronger than the diploid form. But the diploid can also grow rather big in cultivation. They can har dly be distinguished from each other. Therefore, they are not given formal names here. The author fully agree with Prof. T. Reichstein when he said in 1983 that it was hoped that a new nomenclature could be adopted for the cytotypes of species complex in future. The special chromosome number of Pteris deltodon Bak .was counted in this work for the first time. It has 55 bivalents at meiosis of SMC. This number is the only exception in the genus Pteris, and shows that aneuploidy may have taken place in this genus. However, the pos sibility can not be ruled out that P. deltodon is an allotetraploid came from two diploid species respectively with the chromosome number 26 and 29. Pteris gallinopes described by Prof. Ching in i983 is an agamosporous tetraploid with 116 autobivalents at meiosis, different from the related triploid species P. dactylina Hook. and P. henryi Christ. P. ensiformis Burm^。 P. muftifida Poir. and P. semipinnata L. are sexual tetraploids with n=58. P. excelsa Gaud. and P. oshimensis Hieron. var. paraemeiensis Ching are agamosporous triploids with n = 87 autobivalents. P. wallichiana Agardh is a sexual diploid with n=29. The high frequency of polyploids and agamospory among these random sampled Chinese species futher confirms the conclusion that both polyploidy and apomixis have played an important role in speciation and evolution of the genus Pteris. Pteridium aquilimum (L.) Kunh var. latiusculum (Desv.) Underw. ex Heller and Histiopteris incisa (Thunb.) J. Sm. have n=52 and n=96 respectively. They are both sexual tetraploids. Their chromosome numbers show again that the genera Pteridium and Histiopteris are distinquished from the genus Pteris by different basic numbers. This project is supported by the National Natural Science Foundation of China.     

New Cases of Parthenogenesis and Polyploidy in the Genus Ramazzottius (Tardigrada,Hypsibiidae) and a Hypothesis Concerning Their Origin

Summary

Specimens of the genus Ramazzottius Binda and Pilato, 1986 (Eutar-digrada, Hypsibiidae) were obtained from 2 moss and 1 lichen sample(s) collected in the Emilian Apennine Mountains. R. tribulosus was only found in one sample, whereas R. oberhaeuseri was found in all three. The first species had only diploid specimens, with 6 bivalents during the first meiotic division; the second had only females showing various polyploid cytotypes in addition to the diploid bisexual cytotype cited for this area. One of the triploid and the tetraploid cytotypes were characterized by the presence of univalents at oocyte metaphase. In contrast, another cytotype had “bivalents” in triploid number. Though the large number of cytotypes found in a single sample may be attributed to chance, it is better explained by an in loco origin, at least in some cases.     

Studies of the Chinese Woodsiaceae (2) — Comparative Morphology and Anatomy of Mature Sporophytes

the comparative studies of morphology and anatomy of 19 species of Chinese Woodsiaceae are reported in the present paper. It includes anatomy of root, rhizome, rachis and joint on stipe; comparative morphology of the fronds and its parts, trichomes and indusia and an observation of the spores under SEM. The information is applied to discussing phylogeny and systematics briefly. The anatomical studies do provide taxonomic studies with evidence so that they should not be abandoned. For example, the stipe joints of Woodsia have two types, the stipe joint below the attachment point of the base pair of pinnae and the stipe joint just at the attachment point of that; the abscission layer of the former does not have pinna trace in it and the basic chromosome number is 39. However, the abscission layer of the latter does and the basic chromosome number is 41. It is obvious that the anatomical cha-racters can be used for infrageneric subdivision of Woodsia.     

A revision of Dryopteris sect. Diclisodon (Dryopteridaceae) based on morphological and molecular evidence with description of a new species

Dryopteris sect. Diclisodon is a small section of ferns with about 12 species mainly distributed in East Asia. Here, we carried out morphological and phylogenetic analyses of this section. A new species from southwest China, D. gaoligongensis, is described and illustrated. Dryopteris gaoligongensis resembles D. indonesiana and D. sparsa, but differs by having a creeping rhizome and large 4-pinnate fronds. We also show that D. glabrior Ching & Z.Y. Liu is a distinct species; however, because it is a later homonym of D. glabrior Copel., it should be renamed D. renchangiana. We conclude that a species previously known as D. nitidula, also an illegitimate homonym, should be recognized with a new name, D. sinonepalensis. We resolve the phylogenetic position of D. yoroii as sister to other sampled species of D. sect. Diclisodon. Our phylogenetic analyses confirm the distinctiveness of D. gaoligongensis, D. renchangiana, and D. sinonepalensis. A key to species of D. sect. Diclisodon in China is provided.     

中国25个蕨类植物名称原白中排印错误之更正

根据《国际藻类、菌物和植物命名法规》（深圳法规）规则9.2的精神,对我国25个蕨类植物名称的原白中指定的主模式标本错误做了更正,这些植物名称是粤里白、峨眉里白、云南姬蕨、阔基凤丫蕨、川西蹄盖蕨、无盖蹄盖蕨、贡山蹄盖蕨、哈巴蹄盖蕨、假轴果蹄盖蕨、大盖蹄盖蕨、金佛山蛾眉蕨、城口假冷蕨、墨脱红线蕨、镰羽复叶耳蕨、离脉柳叶蕨、弓羽柳叶蕨、木坪贯众、秦岭贯众、强壮鳞毛蕨、西天目鳞毛蕨、百山祖鳞毛蕨、离柄沙皮蕨、毛根蕨、长柄线蕨和长瓦韦。     

Early quantitative method for measuring germination in non-green spores of Dryopteris paleacea using an epifluorescence-microscope technique

A method is described to determine germination by blue-light excited red fluorescence in the positively photoblastic spores of Dryopteris paleacea Sw. This fluorescence is due to chlorophyll as evidenced from 1) a fluorescence-emission spectrum in vivo, where a bright fluorescence around 675 nm is obtained only in red light (R)-irradiated spores and 2) in vitro measurements with acetone extracts prepared from homogenized spores. Significant amounts of chlorophyll can be found only in R-treated spores; this chlorophyll exhibits an emission band around 668 nm, when irradiated with 430 nm light at 21°C.
Compared to other criteria for germination, such as swelling of the cell, coat splitting, greening, and rhizoid formation, which require longer periods after induction for their expression, chlorophyll fluorescence can be used to quantify germination after two days. This result is confirmed by fluence-response curves for R-induced spore germination; the same relationship between applied R and germination is obtained by the evaluation with the epifluorescence method 2 days after the light treatment as compared with the evaluation with bright-field microscopy 5 days after the inducing R.
Using this technique we show for the first time that Ca²⁺ contributes to the signaltransduction chain in phytochrome-mediated chlorophyll synthesis in spores of Dryopteris paleacea .     

宽带蕨属（水龙骨科）的系统学研究

对喜马拉雅和横断山地区特有的水龙骨科的宽带蕨属Platygyria Ching&S.K.Wu植物进行了形态学、分类学、生态和植物地理学的观察与分析,探讨了该属植物的系统位置、亲缘关系和生态适应性,推测宽带蕨属是随着喜马拉雅山脉的隆升,由瓦韦属Lepisorus（J.Sm.）Ching网眼瓦韦群植物适应高寒生态环境演化而来的新生类群。确定宽带蕨属有5种,即川西宽带蕨P.soulieana（Christ）X.C.Zhang&Q.R.Liu、多变宽带蕨P.variabilis Ching&S.K.Wu、耳基宽带     

Spore fitness components do not differ between diploid and allotetraploid species of Dryopteris (Dryopteridaceae)

BACKGROUND AND AIMS: Although allopolyploidy is a prevalent speciation mechanism in plants, its adaptive consequences are poorly understood. In addition, the effects of allopolyploidy per se (i.e. hybridization and chromosome doubling) can be confounded with those of subsequent evolutionary divergence between allopolyploids and related diploids. This report assesses whether fern species with the same ploidy level or the same altitudinal distribution have similar germination responses to temperature. The effects of polyploidy on spore abortion and spore size are also investigated, since both traits may have adaptive consequences. METHODS: Three allotetraploid (Dryopteris corleyi, D. filix-mas and D. guanchica) and three related diploid taxa (D. aemula, D. affinis ssp. affinis and D. oreades) were studied. Spores were collected from 24 populations in northern Spain. Four spore traits were determined: abortion percentage, size, germination time and germination percentage. Six incubation temperatures were tested: 8, 15, 20, 25 and 32 degrees C, and alternating 8/15 degrees C. KEY RESULTS: Allotetraploids had bigger spores than diploid progenitors, whereas spore abortion percentages were generally similar. Germination times decreased with increasing temperatures in a wide range of temperatures (8-25 degrees C), although final germination percentages were similar among species irrespective of their ploidy level. Only at low temperature (8 degrees C) did two allotetraploid species reach higher germination percentages than diploid parents. Allotetraploids showed faster germination rates, which would probably give them a competitive advantage over diploid parents. Germination behaviour was not correlated with altitudinal distribution of species. CONCLUSIONS: The results of this study suggest that (i) relative fitness of allopolyploids at sporogenesis does not differ from that of diploid parents and (ii) neither does allopolyploidization involve a change in the success of spore germination.     

云南鳞毛蕨属毛柄组的分类研究

本文记载了云南产鳞毛蕨属植物18种,其中新种3种,云南新分布的种3种。对一些长期混淆不清的种还进行了分类学讨论。     

云南鳞毛蕨属纤维鳞毛蕨组的分类研究

本文记载云南产鳞毛蕨届纤维鳞毛蕨组植物16种,其中6种为云南新分布,1种为新改级。