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1.
祝正银 《广西植物》2011,31(5):572-574
描述了四川西部天南星属(天南星科)植物一新种,即川西天南星.  相似文献   

2.
Sex allocation models predict that cosexuality is stabilized by high allocation to attractive structures in pollen-limited species or by high allocation to shared structures that contribute to both genders. High investment in unilateral fixed costs favor the evolution of dioecy or gender change. With these predictions in mind, I studied sexual mass allocation at flowering in the monoecious Arum italicum (Araceae) and compared it with information available for its sex labile relative Arisaema dracontium. In A. italicum, 68% of biomass was allocated to structures believed to be involved in pollinator attraction and capture. This allocation pattern contrasts with that of Arisaema dracontium, in which 70% of biomass was allocated to scape, considered to be a unilateral fixed cost. The importance of attractive structures in A. italicum was further supported by a disproportionate increased allocation, in larger inflorescences, to the appendix (an attractive structure) compared to fertile flowers. In addition, an increase in inflorescence mass involved a disproportionate increase in mass allocation to male, rather than female, flowers. This pattern also contrasts with a size-related gender change from male to female in Arisaema species. These findings were consistent with sex allocation model predictions and shed light on the evolution of sex lability in Arisaema species.  相似文献   

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4.
天南星属植物的花粉形态   总被引:2,自引:1,他引:1  
利用扫描电镜对天南星科天南星属(Arisaema)8组25种植物的花粉进行研究(其中,12种前人未观察过,12种中11种为我国特有)。结果显示:本属花粉形态基本一致,即球形,无萌发孔,无覆盖层,具微刺,是一个非常自然的类群。但各个种在花粉粒大小,刺长,刺的形状,刺基部上径,刺的密度和刺间纹饰方面差别较大,可以作为区别种的依据。这进一步证实了前人的结论。花粉形态支持学者们关于天南星属是本科最进化的类群之一的观点。天南星属花粉可能由线花组从花粉大小适中、刺密度居中向大或小、密或疏的方向发展;刺间表面纹饰对探讨组间演化关系意义不大。Murata等对于花粉刺间具较密颗粒为曲序组特征的界定可疑;把A.yunnanense Buchet、A.bathycoleum Hand.-Mazt.和A.prazeri Hook.f.归入曲序组似乎不妥。A.consanguineum Schott和A.fraternum Schott的花粉形态没有支持李恒对这两个种的归并。  相似文献   

5.
高黎贡山是云南与缅甸北部交界的山脉。这一地区的植物区系深受科学界的注意。由于地形险峻,自然植被保存完好,但研究的也较少。高黎贡山是特有现象最丰富的地区。这里有天南星科植物58 种,属于11个属,以南星属为主,含35种。天南星科植物中,10种为高黎贡山所特有,6种为分布到高黎贡山的云南特有种,7种为分布到高黎贡山的中国特有种。植物地理学研究表明高黎贡山的植物区系是东亚植物区系的一部分,是东喜马拉雅植物区系的起源地之一。  相似文献   

6.
The evolution of Arisaema is reconstructed, based on combined sequences (2048 aligned bases) from the chloroplast trnL intron, trnL-trnF spacer, and rpl20-rps12 spacer obtained for species from all 11 sections, including sectional type species and geographically disjunct East African and North American/Mexican species. Analyses were rooted with a representative sample of the closest outgroups, Pinellia and Typhonium, to rigorously test the monophyly of Arisaema. Sections in Arisaema are mostly based on leaf, stem, and inflorescence characters and, with one exception, are not rejected by the molecular data; however, statistical support for sectional relationships in the genus remains poor. Section Tortuosa, which includes eastern North American A. dracontium and Mexican A. macrospathum, is demonstrably polyphyletic. The third New World species, A. triphyllum, also occurs in eastern North America and groups with a different Asian clade than do A. dracontium/A. macrospathum. The genus thus appears to have entered North America twice. Fossil infructescences similar to those of A. triphyllum are known from approximately 18 million-year-old deposits in Washington State and can serve to calibrate a molecular clock. Constraining the age of A. triphyllum to 18 million years (my) and applying either a semiparametric or an ultrametric clock model to the combined data yields an age of approximately 31-49 my for the divergence of A. dracontium/A. macrospathum from their Asian relatives and of 19-32 my for the divergence between African A. schimperianum and a Tibetan/Nepalese relative. The genus thus provides an example of the Oligocene/Miocene floristic links between East Africa, Arabia, the Himalayan region, China, and North America. The phylogeny also suggests secondary loss of the environmental sex determination strategy that characterizes all arisaemas except for two subspecies of A. flavum, which have consistently bisexual spathes. These subspecies are tetraploid and capable of selfing, while a third subspecies of A. flavum is diploid and retains the sex-changing strategy. In the molecular trees, the sex-changing subspecies is sister to the two non-sex-changing ones, and the entire species is not basal in the genus.  相似文献   

7.
Summary. Arisaema candidissimum W. W. Sm. (Araceae) was last recorded in its native China in 1932, but in 1993 and 1994 it was again observed in Yunnan Province. The colour variation, history and rediscovery of the species are discussed.  相似文献   

8.
Arisaema species exhibit gender diphasy, or sex change, where individual plants produce either male, monoecious or female inflorescences depending on their size. Three basic sex-change patterns have been described in Arisaema. Type I species change between male and monoecious phases, type II species change between male, monoecious and female phases, while type III species change between male and female phases. Theoretical models suggest that sex ratios should be biased toward males, the sex with the lowest cost of reproduction. The goal of this study was to examine sex-ratio variation among Arisaema species that differ in sex-change patterns. Data from an extensive literature review, consisting of all available studies reporting Arisaema sex ratios, were combined with data from extensive field surveys of Arisaema dracontium and Arisaema triphyllum in southern Indiana, USA. This data set contains nearly 30 000 plants from 12 species. All species conformed to either the type I or type III pattern of sex change. There was little evidence for a distinct type II pattern of sex change, given that plants with monoecious inflorescences were rare relative to plants with pistillate inflorescences. The mean sex ratio in type I species (79.9% male) was significantly greater than in type III species (63.7% male). The data are consistent with the prediction that type I species are likely to have greater costs associated with female reproduction. We suggest that all Arisaema species have similar patterns of floral development, but differ in their ontogenetic patterns for male and female flowering.  相似文献   

9.
光镜、电镜下观察了天南星科天南星族下斑龙芋属2 个种及近缘属13 个种植物的叶表皮形态特征。实验结果显示, 4 属植物的叶表皮组成及其形态特征较相似, 属间不存在明显差异, 但某些特征在种间存在差异, 可作为种的鉴别特征。叶表皮特征支持将单籽犁头尖和昆明犁头尖两个种合并为一个种。15 个种的气孔器均具有2 个副卫细胞, Stebbins and Khush 认为这是气孔器类型中较具2 个以上副卫细胞更进化的一种类型, 而天南星科大多数族的气孔器都具有2 个以上的副卫细胞, 这也证明了天南星族是天南星科较进化的族。  相似文献   

10.
Leaf epidermis of 2 species in genus Sauromatum Schott were examined under light microscope and scanning electron microscope ( SEM) and compared with that of 13 species in genera Typhonium, Pinellia and Arisaema in the same tribe Area of Araceae . The result reveals that the characters of leaf epidermis between the several genera generally are very similar . However , some of the characters in the species of the same genus are variable and can be used to identify its species . The characters of leaf epidermis support to merge Typhonium kunmingense into Typhonium calcicolum . The stomata apparatus of 15 species are all brachyparacytic types with 2 subsidiary cells . This type of stomata apparatus is considered more evolutional than that with more than 2 subsidiary cells which existed in majority tribes of Araceae . This also verify some taxonomists’viewpoint that tribe Area is more evolutional in family Araceae .  相似文献   

11.
斑龙芋属(天南星科)及近缘属植物的叶表皮形态   总被引:3,自引:0,他引:3  
光镜、电镜下观察了天南星科天南星族下斑龙芋属2个种及近缘属13个种植物的叶表皮形态特征。实验结果显示,4属植物的叶表皮组成及其形态特征较相似,属间不存在明显差异,但某些特征在种间存在差异,可作为种的鉴别特征。叶表皮特征支持将单籽犁头尖和昆明犁头尖两个种合并为一个种。15个种的气孔器均具有2个副卫细胞,Stebbins andKhush认为这是气孔器类型中较具2个以上副卫细胞更进化的一种类型,而天南星科大多数族的气孔器都具有2个以上的副卫细胞,这也证明了天南星族是天南星科较进化的族。  相似文献   

12.
Arisaema lushuiense G. W. Hu & H. Li, a new species of Araceae from Gaoligong Mountains in northwestern Yunnan, China, is described and illustrated. It is similar and closely related to A. auriculatum Buchet, but differs by its basically green spathe with semi‐rotund to broadly ovate, 6–8 mm long auricles; the appendix of the spadix is 3.5–5.0 cm long and the apex of the appendix depressed with faint longitudinal ridges and grooves, slightly curved forward, with purplish black color, and exserted 1.0–1.5 cm from the spathe throat.  相似文献   

13.
Arisaema saddlepeakense is described from Saddle Peak, Andaman Islands, India. It belongs to section Fimbriata and is allied to A. album.  相似文献   

14.
? Premise of the study: We developed novel microsatellite markers in Arisaema serratum, a perennial herb that possesses pitfall flowers and exhibits labile sex expression, to facilitate research on parentage and pollination biology in this species. ? Methods and Results: By using procedures for enrichment of desired microsatellite-containing fragments and PCR-based isolation of microsatellite arrays, we detected 18 novel microsatellite loci. Thirteen were highly polymorphic: the number of alleles per locus ranged from six to 46, the observed heterozygosities ranged from 0.320 to 0.940, and the expected heterozygosities ranged from 0.440 to 0.976. Nine of the 13 markers successfully amplified regions in congeneric species. ? Conclusions: These highly polymorphic markers will facilitate further studies on the mode of pollination and other aspects of reproductive biology in A. serratum.  相似文献   

15.
本文描写了高黎贡山地区察隅南星Arisaema bogneri P.Boyce et H.Li、腾冲南星五叶变种A.tengtsunense H.Li var.pentaphyllum H.Li、缅甸南星A.burmaense P.Boyce et H.Li;第一次报道会泽南星A.dahaiense H.Li在高黎贡山的分布,对该种的果序和果实作了补充描述。  相似文献   

16.
17.
Lin J  Zhou X  Pang Y  Gao H  Fei J  Shen GA  Wang J  Li X  Sun X  Tang K 《Bioscience reports》2005,25(5-6):345-362
A novel agglutinin gene was cloned from Arisaema lobatum using SMART RACE-PCR technology. The full-length cDNA of Arisaema lobatum agglutinin (ala) was 1078 bp and contained a 774 bp open reading frame encoding a lectin precursor (proproprotein) of 258 amino acid residues with a 23 aa signal peptide. ALA contained three mannose-binding sites (QXDXNXVXY) with two-conserved domains of 45% identity, ALA-DOM1 and ALA-DOM2. The three-dimensional structure of ALA was very similar to that of GNA (Galanthus nivalis agglutinin). ALA shared varying identities, ranging from 40% to 85%, with mannose-binding lectins from other species of plant families, such as Araceae, Alliaceae, Iridaceae, Lillaceae, Amaryllidaceae and Bromeliaceae. Genomic sequence of ala was also cloned using genomic walker technology, and it was found to contain three putative TATA boxes and eight possible CAAT boxes in the 5′-flanking region. No intron was found within the region of genomic sequence. Southern blot analysis indicated that the ala belonged to a multi-copy gene family. Expression pattern analysis revealed that the ala preferentially expressed in the tissues with the higher expression being found in spadix, bud, leaf, spathe and tuber. The cloning of the ala gene not only provides a basis for further investigation of its structure, expression and regulation mechanism, but also enables us to test its potential role in controlling pests and fungal diseases by transferring the gene into plants in the future.  相似文献   

18.
Traditional plant use in Nepal has been documented for millennia. The importance of plants as medicine has not diminished in any way in recent times, and traditional medicines are still the most important health care source for the vast majority of the population. This paper examines the ethnobotany and traditional use of plants extracted from the vulnerable alpine zone in the Dolpa, Humla, Jumla and Mustang districts of Nepal. The results of this ethnobotanical study indicate that a very large number of plant species is used as traditional medicines. There were 107, 59, 44 and 166 species of ethnomedicinal importance in surveyed areas of Dolpa, Humla, Jumla and Mustang district respectively. Of these, 84 common species, used at least in two districts, were selected to enumerate their ethnomedicinal properties. The 84 species belonged to 75 genera and 39 families. The commonest species in this pharmacopoeia were: Allium wallichii, Cordyceps sinensis, Dactylorhiza hatagirea, and Rheum australe. A total of 21 species were most common in three districts and 59 in two districts. The genera Aconitum, Allium, Arisaema, Berberis, Corydalis, Gentiana, Hippophae, Juniperus and Rhododendron each possessed two species with ethnomedicinal use. Labiatae was the most medicinally important family with five species used, followed by Araceae, Compositae, Liliaceae, Polygonaceae, Ranunculaceae, Scrophulariaceae and Umbelliferae, each contributing four species.  相似文献   

19.
Pistia stratiotes (water lettuce) and Lemna (duckweeds) are the only free-floating aquatic Araceae. The geographic origin and phylogenetic placement of these unrelated aroids present long-standing problems because of their highly modified reproductive structures and wide geographical distributions. We sampled chloroplast (trnL-trnF and rpl20-rps12 spacers, trnL intron) and mitochondrial sequences (nad1 b/c intron) for all genera implicated as close relatives of Pistia by morphological, restriction site, and sequencing data, and present a hypothesis about its geographic origin based on the consensus of trees obtained from the combined data, using Bayesian, maximum likelihood, parsimony, and distance analyses. Of the 14 genera closest to Pistia, only Alocasia, Arisaema, and Typhonium are species-rich, and the latter two were studied previously, facilitating the choice of representatives that span the roots of these genera. Results indicate that Pistia and the Seychelles endemic Protarum sechellarum are the basalmost branches in a grade comprising the tribes Colocasieae (Ariopsis, Steudnera, Remusatia, Alocasia, Colocasia), Arisaemateae (Arisaema, Pinellia), and Areae (Arum, Biarum, Dracunculus, Eminium, Helicodiceros, Theriophonum, Typhonium). Unexpectedly, all Areae genera are embedded in Typhonium, which throws new light on the geographic history of Areae. A Bayesian analysis of divergence times that explores the effects of multiple fossil and geological calibration points indicates that the Pistia lineage is 90 to 76 million years (my) old. The oldest fossils of the Pistia clade, though not Pistia itself, are 45-my-old leaves from Germany; the closest outgroup, Peltandreae (comprising a few species in Florida, the Mediterranean, and Madagascar), is known from 60-my-old leaves from Europe, Kazakhstan, North Dakota, and Tennessee. Based on the geographic ranges of close relatives, Pistia likely originated in the Tethys region, with Protarum then surviving on the Seychelles, which became isolated from Madagascar and India in the Late Cretaceous (85 my ago). Pistia and Protarum provide striking examples of ancient lineages that appear to have survived in unique or isolated habitats.  相似文献   

20.
Other than studies on sex-labile Arisaema species, studies of gender patterns in Araceae are scarce. The modification of phenotypic and functional gender was investigated in three populations of the monoecious Arum italicum Miller. The probability of reproduction and the number of inflorescences produced increased with plant size, and flower number (total, male, staminodes, female, pistillodes) increased with both plant and inflorescence sizes. However, plant and inflorescence sizes were poor predictors of floral sex ratio (female to male flower ratio). In contrast, change in floral sex ratio towards increasing femaleness was found among inflorescences sequentially produced by a plant. This change could not be explained by either a decrease in inflorescence size or a change in the mating environment. Differences in functional gender did not appear to be related to plant size or stage in the flowering period. Instead, different patterns of functional gender were found between plants with different number of inflorescences. Multi-inflorescence plants showed a functional gender around 0.5, while plants with one inflorescence showed a more extreme functional gender (either male, female, or functionally sterile). Sex of flowers in this species did not seem to exhibit a phenotypic trade-off.  相似文献   

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