广西被子植物二新记录属

在第四次中药资源普查中采集了大量标本,经过对这些标本进行仔细鉴定并查阅相关资料,确定其中两号标本为香茜属(Carlemannia Benth.)和粘腺果属(Commicarpus Standl.)植物。这两属植物在广西尚无报道,为首次记录。香茜属植物叶对生,子房下位,无托叶,雄蕊仅有2枚,这和茜草科相似但又不同,系统位置较混乱,以前曾放于茜草科( Rubiaceae)和忍冬科( Caprifoliaceae)中,最近该属和蜘蛛花属独立成香茜科( Car-lemanniaceae)。该属植物共有3种,沿喜马拉雅山脉向东一直分布到缅甸、越南北部。我国西藏东南、云南南部、广西西北部分布一种即香茜( Carlenannia chinenesis Hook. f.)。粘腺果属是紫茉莉科( Nyctaginaceae)主产热带地区的1个属,全世界约25种分布于热带非洲和阿拉伯半岛南部,在南亚、东南亚和墨西哥至热带美洲也有少量分布。中国产2种,其中广西产1种即中华粘腺果[ Commiaicarpus chinensis ( L.) Heim.]。该种植物分布广泛,从南亚次大陆向东至中南半岛、马来半岛,向北到我国西沙群岛、海南岛以及广州附近,在广西首次记录,产凤山县和凌云县。     

Karyomorphology ofCrossostylis (Rhizophoraceae)

We present the first report on somatic chromosome numbers and morphology in eight of 13 recorded species ofCrossostylis, one of inland genera of Rhizophoraceae. The chromosome number ofCrossostylis is 2n=28 in all species examined; therefore, the genus hasx=14, a number which is the smallest and unknown elsewhere in the family. Based onCrossostylis raiateensis, we further present that 24 of 28 chromosomes at metaphase have centromeres at median position, and the remaining four at submedian or subterminal position. The chromosome morphology seems to imply thatCrossostylis might be a tetraploid with the original base numberx=7, but an extensive study in the other inland genera is needed to find such a small chromosome number.     

四角果科（Carlemanniaceae）的系统位置评述

四角果科（Carlemanniaceae）科下有四角果属Carlemannia（3种）和蜘蛛花属Silvianthus（1种1亚种）。这两属建立之初均置于茜草科,此后又被多个分类及系统学家将它们移至忍冬科;1965年由Airy Shaw将它们从忍冬科独立成四角果科,得到了部分学者的赞同,但其系统位置仍存在争议,认为与与苦苣苔科、虎耳草科、马鞭草科和绣球花科等科的关系错综复杂;科下两属间的关系也仍然值得探讨。APGII认为四角果科与木樨科素馨属或女贞属近缘,但支持率不高。本文对四角果属和蜘蛛花属系统位置的研究和现状进行了评述;将Silvianthus bracteatus ssp. tonkinensis (Gagnep.) H. W. Li作为线萼蜘蛛花Silvianthus bracteatus ssp. clerodendroides (Airy Shaw) H.W.Li的异名归并;并对今后的研究提出了建议。     

Basic chromosome numbers of terrestrial orchids

The chromosome numbers of forty-one Brazilian species belonging to 11 genera of preferentially terrestrial orchids (subfamilies Cypripedioideae, Spiranthoideae, Orchidoideae, and Vanilloideae) were examined. Previous records for these subfamilies were reviewed in order to identify the ancestral chromosome numbers of terrestrial orchids. The variation observed within the subfamilies Spiranthoideae (2n=28, 36, 46, 48 and 92), and Orchidoideae (2n=42, 44, ca. 48, ca. 80, 84, and ca. 168) was similar to that previously reported in the literature. In the subfamily Spiranthoideae, some species of Prescottia (subtribe Prescottiinae) and some genera of Spiranthinae showed a bimodal karyotype with one distinctively large pair of chromosomes. The analysis of chromosome numbers of the genera in subfamilies revealed the predominance of the polyploid series 7, 14, 21, 28, 42 with a dysploid variation of ±1 in each ploidy level. These results suggest that the basic chromosome number of terrestrial orchids is x₁=7 for the subfamilies Spiranthoideae and Orchidoideae, as well as other Epidendroid orchids, and that the majority of the genera are composed of palaeopolyploids.     

A review of chromosome cytology in Hyacinthaceae subfamily Ornithogaloideae (Albuca, Dipcadi, Ornithogalum and Pseudogaltonia) in sub-Saharan Africa

The chromosome cytology of Hyacinthaceae subfamily Ornithogaloideae is reviewed within the framework of a recent molecular-based classification, with particular emphasis on its center of diversity in sub-Saharan Africa. We also provide new chromosome counts for sections that are unknown or poorly known cytologically. Albuca subgen. Namibiogalum (9 spp.) probably has an ancestral base number of x = 10 but subgen. Albuca (± 70 spp), subgen. Monarchos (9 spp.) and subgen. Osmyne (36 spp.) have x = 9. The pattern in subgen. Urophyllon (3 spp.) is remarkable: although x = 6 is likely, the species in the section exhibit a range of 2n = 12, 10, 8, 6 and 4 (exclusive of polyploidy). All karyotypes have three large chromosome pairs and a variable number of small chromosomes. Pseudogaltonia (2 spp.) has x = 9 and Dipcadi (26 spp.) possibly x = 9 in series Uropetalum and x = 6 in series Dipcadi, which exhibits a pattern of descending dysploidy leading to n = 3 in D. marlothii. In Ornithogalum (± 130 spp.) chromosome numbers are known for only 24 of the ± 84 sub-Saharan species, mostly from subgen. Aspasia and subgen. Ornithogalum sect. Linaspasia, both of which have x = 6, and from subgen. Galtonia, which has x = 8. In contrast, x = 7 is basic for the Eurasian sects. Honorius and Melophis, and x = 18 seems likely for sect. Cathissa. Sect. Ornithogalum, the cytology of which we does not examine in detail, may have x = 9. Polyploidy is apparently rare in the sub-Saharan African ornithogaloids, in marked contrast to the high frequency of polyploidy among Eurasian species. In Albuca just 3 or possibly 4 sub-Saharan species (9% or 13% of those counted) are exclusively polyploid and 5 more have diploid and polyploid races; and in sub-Saharan Ornithogalum, only the tropical O. gracillimum is exclusively polyploid, and the western southern African O. hispidum has diploid and polyploid races.     

Chromosome numbers of miscellaneous Malagasy Acanthaceae

Meiotic chromosome numbers are reported for 12 species in eight genera of Acanthaceae from Madagascar. Chromosome numbers of 11 species are reported for the first time. Counts inMendoncia (n=19) andNeuracanthus (n=20) are the first for these genera. A new chromosome number (n=30) is reported inJusticia. Systematic implications of the chromosome counts are addressed and basic chromosome numbers for these eight genera of Malagasy Acanthaceae are discussed.     

Chloroplast DNA restriction site data support a narrowed interpretation ofEupatorium (Asteraceae)

Chloroplast DNA (cpDNA) restriction site analysis was used to assess relationships among samples of Eupatorieae from eastern North America. A total of 270 cpDNA variants was recorded from 35 species using 13 restriction enzymes. Phylogenetic analysis usingGalinsoga, Flaveria, andHelianthinae as outgroups indicated that samples ofAgeratina, Hofmeisteria, Mikania, andStevia, each of which have relatively high base chromosome numbers, formed an unresolved basal polytomy. The remaining samples examined formed a well-supported clade, within which there was a split betweenBrickellia, which hasx = 9, and a number of genera withx = 10. Within thex = 10 clade, there was an unresolved trichotomy, with one group ofAgeratum, Conoclinium, Fleischmannia, andCritonia, a second ofLiatris andTrilisa, and a third ofEupatorium s.s. Within theEupatorium s.s. clade there were three further clades, withE. sect.Verticillata diverging first, and a subsequent split between species originating from North America and those from Asia. The cpDNA restriction site data provided support for a relatively narrow interpretation ofEupatorium, and indicated that a high chromosome base number is plesiomorphic for Eupatorieae.     

The neotropical angiosperm familiesBrunelliaceae andCaryocaraceae: First karyosystematical data and affinities

Chromosome numbers are polyploid, 2n = 28 inBrunellia comocladiifolia andB. mexicana, and 2n = 46 inCaryocar brasiliense, C. microcarpum andC. villosum. The chromosome are small in both genera, with a length of ca. 1,6-0,4µm. Interphase nuclei correspond to the prochromosomal and the chromocentric type, respectively. This is in conformance with the systematic placement ofBrunelliaceae intoCunoniales, and ofCaryocaraceae intoTheales. Brunellia exhibits affinities to various other orders ofRosidae (andHamamelididae), and is suggested to be primarily apetalous. On a comparative basis, the chromosome numbers found in both families are interpreted as paleopolyploid (4 x and 6 x). This apparently is in correspondence with their rather primitive features, systematic isolation, relatively depauperate status, and evidently great age.     

Karyological studies of four genera of theChloranthaceae

Karyological observations on 7 species and 2 varieties of 4 genera belonging to theChloranthaceae demonstrate the presence of three basic chromosome numbers within the family, i.e., x = 8 (Hedyosmum), 13 (Ascarina) and 15 (Chloranthus, Sarcandra). The karyomorphology ofChloranthus andAscarina is similar, whereasSarcandra andHedyosmum display unique characteristics. Both karyological aspects, i.e., chromosome number and karyomorphology, demonstrate remarkable diversity ofChloranthaceae and complex relationships between its genera. A distant affinity betweenChloranthaceae andPiperales is suggested.Presented at the XV International Botanical Congress Yokohama 1993, Symposium on Relationships and Evolution of Primitive Angiosperms: Multidisciplinary Approaches.     

Zur systematischen Stellung der GattungProckia: Karyologie und Epidermisskulptur im Vergleich zuFlacourtia (Flacourtiaceae),Grewia (Tiliaceae) und verwandten Gattungen

Detailed analyses of karyology and leaf morphology do not support relationships betweenFlacourtiaceae andTiliaceae. In spite of different chromosome numbers,Prockia (2n = 18),Flacourtia (2n = 22) andRawsonia (2n = 22) are very similar in karyomorphology, indicating a certain karyological uniformity withinFlacourtiaceae. Lacistema (2n = ca. 62) appears more isolated. On the other hand, theTiliaceae Grewia (2n = 18) andLuhea (2n = 36) have much in common and differ remarkably from the Flacourtiaceous genera. The salicoid leaf-teeth ofProckia are also found inIdesia, but never inTiliaceae. Epidermis ultrastructure reveals certain relationships betweenProckia andFlacourtia in contrast to the strongly differingGrewia. Idesia has a rare und unique epidermis sculpture. — Basic chromosome numbers and chromosomal evolution within theFlacourtiaceae are discussed.

     

Cytology and systematics in JapaneseArisaema (Araceae)

Chromosome numbers are determined from 37 populations attributed to 22 taxa of JapaneseArisaema. Of them, chromosome numbers ofA. limbatum var.conspicuum (2n=26),A. minus (2n=26),A. nambae (2n=28) andA. seppikoense (2n=26) are determined for the first time. New chromosome numbers, 2n=26, are reported forA. aequinoctiale, A. limbatum, A. stenophyllum, A. undulatifolium andA. yoshinagae. Three modes of basic chromosome numbers,x=14,x=13 andx=12, occur in JapaneseArisaema. Precise karyotypic comparisons of 20 taxa reveal that taxa withx=14 andx=13 share 26 major chromosome arms and have an obvious chromosomal relationship. One of two submeta-centric chromosomes inx=13 corresponds to two telo-centric chromosomes inx=14. InA. ternatipartitum with 2n=6x=72, ten out of 12 basic chromosomes are the most similar in size and arm ratio with larger ten chromosomes ofA. ringens among JapaneseArisaema examined. A basic chromosome number ofx=14 is the commonest in the genusArisaema and the remaining basic chromosome numbers,x=13 andx=12, seem to be derived through dysploidal reduction by translocating large segments of major arm of telo-centric chromosome onto other minor arm of telo-centric followed by loss of the remainings including a centromere, and by loss of two telo-centrics fromx=14, respectively. Some systematic problems of JapaneseArisaema are discussed based on new cytological data.Arisaema hatizyoense, A. minus andA. nambae are accepted as independent species.     

The phylogenetic position of Apterosperma (Theaceae) based on morphological and karyotype characters

Classifications of Theaceae have usually placed the endangered monotypic genus Apterosperma in tribe Schimeae (x=18), whereas recent molecular phylogenetic evidence supports its transfer to tribe Theeae (x=15). Molecular data have not resolved the phylogenetic position of Apterosperma within Theeae. We investigated the chromosome number and karyotype of Apterosperma in the context of molecular and morphological phylogenetic evidence to provide further insight into the placement of Apterosperma within Theaceae. The chromosome number and karyotype was found to be 2n = 30 = 26m + 4sm, consistent with the transfer of Apterosperma to tribe Theeae. When the chromosome data were incorporated into a data set of 46 other nonmolecular characters, Apterosperma was placed as the first-diverging lineage within the clade comprising tribe Theeae. This supports its placement based on molecular data. The low intrachromosomal asymmetry (type 1A) of Apterosperma, presumably ancestral for the family, is also consistent with this placement. Character optimization strongly supports a base chromosome number of x=15 for tribe Theeae. Because of variable and sometimes conflicting chromosome count reports of species in tribes Schimeae and Stewartieae, the base chromosome number of Theaceae could be either x=15 or 17.     

Another perspective on cytoevolution in Lobelioideae (Campanulaceae)

The Lobelioideae is a cosmopolitan group whose cytoevolution is discussed on a model of primitively high diploid chromosome numbers, in which x = 14 is relatively plesiomorphic and x = 21 may be even more plesiomorphic. This model is suggested from the high frequency of lobelioid genera with x = 14, the probably plesiomorphic condition of x = 17 in the sister group Campanuloideae (Campanulaceae), and the primitive x = 15 in Stylidiaceae (Campanulales). It contrasts with that for a primitive x = 7 and paleopolyploidy to higher chromosome numbers. In our analysis, the genus Lobelia shows three broad cytoevolutionary groups, which probably have phylogenetic and infrageneric taxonomic significance: (1) woody diploids with x = 21 in Chile and woody diploids with x = 14 in Africa, Asia, and Hawaii; (2) herbaceous diploids with several series of dysploid chromosome numbers n = 19, 13, 12, 11, 10, 9, 8, 7, 6, mainly in Africa and Australia; (3) widespread and speciose herbaceous taxa based on a very derived n = 7, with recent frequent euploid rises (neopolyploidy) at or below the species level in subgenus Lobelia and allied or segregate genera. Other woody and herbaceous lobeliad genera have comparable cytoevolutionary patterns. New chromosome counts for Australian Lobelia, Pratia, and Isotoma illustrate the last two cytoevolutionary groups.     

Distribution of sequences related to the Bg transposable element of maize in Zea and related genera

Thirty-four accessions from Zea and 10 accessions from related genera were assayed for the presence of Bg, a transposable element originally found in maize (Zea mays ssp. mays). Bg-like sequences, identified as hybridizing bands on Southern blots, were visualized in all Zea accessions and were present in approximately equal numbers in teosinte and maize. With the exception of Tripsacum dactyloides, all accessions from related genera failed to hybridize with the Bg probes, even at reduced stringency. A comparison of the restriction patterns of related inbred lines revealed numerous common hybridizing fragments. An index of molecular similarity (MS) was used to determine the degree of similarity between pairs of inbred lines. Computed MS values endorse an inbred relationship and are in good agreement with published results of cluster analysis on these inbred lines.     

Pathways of karyological differentiation in palms (Arecaceae)

Karyological data are given for 56 palm taxa coming from all 6 palm subfamilies. In 11 genera and 17 species, chromosome numbers are reported for the first time. Most chromosome numbers in palms range between 2n = 36 and 2n = 26 in dysploid series. Species of the same genus usually exhibit identical chromosome numbers which additionally may be constant in larger groups of closely related genera (Coryphoideae trib.Corypheae with nearly always 2n = 36,Arecoideae subtribesEuterpeinae andRoystoneinae with 2n = 36,Arecoideae subtrib.Butiinae with mostly 2n = 32). Polyploidy among palms is of minor significance but the endemic Madagascan genusVoanioala (2n = 606 ± 3) is the most striking exception. — With respect to structure of interphase nuclei and longitudinal differentiation of prophase and metaphase chromosomes, the palm family is highly differentiated. Euchromatin types with different prophase condensation properties and fluorochrome and C-banding patterns of heterochromatin permit a discrimination of several subfamilies on the nuclear level (Arecoideae, Ceroxyloideae, Nypoideae, Phytelephantoideae, Calamoideae).Arecoideae andCeroxyloideae, andNypoideae andPhytelephantoideae have some features in common. Subfam.Coryphoideae s. l. is a non-uniform group. — Nuclear characters among palms exclusively found in recentCoryphoideae subtrib.Thrinacinae link palms with other monocotyledons. Most probably, such a nuclear condition represents an ancestral state in the evolution of palm genomes within subfam.Coryphoideae s. l., but also the conspicuous nuclear characters of the other modern palm subfamilies appear to be derived from a similar starting point, since transitional character states are still present in subfam.Calamoideae and some taxa of subfam.Arecoideae. Early karyoevolution in palms obviously did not involve numerical change of the ancient chromosome number of 2n = 36 which started subsequently, as a dysploid reduction in numerous parallel series, independent in subfam.Coryphoideae (2n = 36 to 2n = 28),Calamoideae (2n = 36 to 2n = 26),Ceroxyloideae (2n = 34 to 2n = 26), andArecoideae (2n = 36 to 2n = 28). Possible mechanisms of karyological change are discussed. — Karyological characters are compared to morphological, ecological, taxonomical, and chorological features, and give some new insight into older and more recent phases of palm evolution. (1) Strong deviations in vegetative or floral morphology are often accompanied by major karyological differences, and sometimes the direction of advancement can be traced through intermediate stages. (2) Apart fromCoryphoideae subtrib.Thrinacinae, the strongest concentration of apparently original karyological traits is found in the more basal members of each subfamily. (3) The most successful and actively radiating colonizers of the forest floors in evergreen tropical forests which belong to completely different subfamilies (Old WorldLicuala, New WorldChamaedorea andGeonoma), appear to be very advanced karyologically.     

A phylogenetic analysis of chloroplast DNA restriction site variation inPoaceae subfam.Pooideae

A phylogenetic analysis was conducted on chloroplast DNA restriction site variation in 34 genera of grasses (familyPoaceae), including 28 genera from subfam.Pooideae (representing tribesAveneae, Brachypodieae, Bromeae, Meliceae, Poeae, Stipeae, andTriticeae) and representatives of three other subfamilies,Arundinoideae, Oryzoideae, andPanicoideae. Analyses of all 34 genera always distinguishedPooideae as monophyletic, regardless of which nonpooid genus functioned as outgroup; six separate analyses of all 28 pooid genera, each including one of the six nonpooid genera as outgroup, resolved five identically-constituted clades withinPooideae (in four cases), or (in the other two cases) yielded results that were less well resolved, but not in conflict with those of the other four analyses. The four best-resolved analyses distinguishedMeliceae as the earliest diverging lineage withinPooideae, andStipeae as the next. Above the point of divergence ofStipeae is a dichotomy between supertribeTriticodae (including tribesBrachypodieae, Bromeae, andTriticeae), and a clade comprisingPoeae andAveneae. The analysis supports some tribal realignments, specifically the assignment ofBriza, Chascolytrum, Microbriza, andTorreyochloa toAveneae, andArctagrostis, Catabrosa, andSesleria toPoeae. The analysis also suggests that the pooid spikelet (i.e., glumes shorter than lemmas and florets two or more) is plesiomorphic inPooideae, and that spikelets with one floret, and those with glumes longer than the first lemma, each have evolved more than once withinPooideae. Results also indicate that small chromosomes and chromosome numbers based on x=c. 10–12 are plesiomorphic withinPooideae. Alternative states of these characters (chromosomes large, chromosome numbers based on x=7) are interpreted as synapomorphies or parallelisms of clades that includeTriticodae, Aveneae, andPoeae. Lanceolate lodicule shape may be a synapomorphy of the clade that includesStipeae, Triticodae, Aveneae, andPoeae, and loss of lodicule vascularization a synapomorphy of the entirePooideae.     

Genome size in Bulgarian Centaurea s.l. (Asteraceae)

Thirty-nine species and subspecies of the genera Centaurea, Colymbada, Psephellus and Cyanus (all included in Centaurea s.l.) including many rare and endemic taxa of preponderantly Bulgarian distribution have been investigated with Feulgen DNA image densitometry for holoploid and monoploid genome size (C- and Cx-values). Cyanus varies gradually 2.17-fold between 0.74 pg and 1.56 pg (1Cx). In the remaining taxa two major genome size groups are found, which differ about 1.8-fold in Cx-value. Low values occur in Centaurea subgenera Acrolophus, Solstitiaria, Phalolepis (0.77 pg to 0.90 pg, 1Cx) and Jacea (0.95 pg to 1.09 pg, 1Cx), high values in the genera Colymbada (1.65 pg to 1.93 pg, 1Cx) and Psephellus (1.79 pg, 1Cx, in P. marschallianus). Cx-values support a distinction of Colymbada from Centaurea. Genome size variation is discussed with regard to phylogeny, life form (annual versus perennial), polyploidy, chromosome basic numbers, altitude of occurrence and climate, endemism, and rarity.     

国产驴蹄草的细胞地理学研究

为探讨国产毛茛科(Ranunculaceae)驴蹄草属(Caltha)两种植物的演化,该文利用传统染色体压片技术和流式细胞术,并结合前人染色体研究结果,对我国驴蹄草23个居群和花葶驴蹄草10个居群进行了细胞学研究。结果表明:驴蹄草是由四倍体(2n=4x=32)、六倍体(2n=6x=48)和八倍体(2n=8x=64)构成的多倍体复合群,花葶驴蹄草具有四倍体(2n=4x=32)和八倍体(2n=8x=64)两种倍性水平。驴蹄草和花葶驴蹄草均是四倍体较为常见,目前尚未见有二倍体报道。由于驴蹄草和花葶驴蹄草大部分居群采自中国青藏高原地区,可能在冰期时存在古二倍体,其适应性较弱,逐渐被其他的倍性取代,这是由于不同细胞型对环境适应性的结果。驴蹄草可能存在两条进化路线:一条是从甘肃到达云南;另一条是从西藏到达云南。前期分子系统学研究显示花葶驴蹄草与驴蹄草的亲缘关系较近,该研究结果中花葶驴蹄草染色体比驴蹄草要小,花葶驴蹄草可能比驴蹄草相对进化。目前花葶驴蹄草只有10个居群,还需进一步增加居群量来解析其演化路线。     

Ultrastructure of nuclear inclusions and the separation ofVerbenaceae andOleaceae (incl.Nyctanthes)

TEM observations were carried out on 40 taxa of the familyVerbenaceae and 35 taxa of the familyOleaceae, in order to ascertain distribution, ultrastructure and morphology of the intranuclear proteinic inclusions in the mesophyll parenchymatic cells. The investigated genera amount to some 25% and 60% respectively of the genera of the two families. Inside theVerbenaceae, lamellar inclusions (L-type) occur in 6 out of 23 investigated genera: they are mostly present inside the tribesCitharexyleae andVerbeneae (both belonging toVerbenoideae), while they are absent in other subfamilies. All of the investigatedOleaceae genera show intranuclear crystalline inclusions (C 1-type) of three different shapes. Among theAsteridae this is a character peculiar toOleaceae. They appear to be a well defined natural group, including the controversial genusNyctanthes.     

Chromosome numbers of the European seagrasses

The chromosome numbers of the five European seagrasses have been determined in material from several sites along the coasts of the Atlantic Ocean, the North Sea and the Mediterranean:Zostera marina L., 2n = 12;Z. noltii Hornem., 2n = 12;Posidonia oceanica (L.)Delile, 2n = 20;Cymodocea nodosa (Ucria)Aschers., 2n = 14, 2n = 28;Halophila stipulacea (Forsk.)Aschers., 2n = 18. The difference in chromosome morphology betweenZ. marina andZ. noltii supports the division of the genus into two subgenera.