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1.
A quantitative comparison was conducted on the foliage development during sporophyte development of three allopatric ferns in cool temperate and subalpine regions of Hokkaido and Tirol, European Alps. The foliage development ofDryopteris crassirhizoma, D. coreano-montana andD. filix-mas was quantitatively described by the leaf development (NV, number of veins); NV correlates the leaf-shape complexity from a circle (DI, L/2(3.14×S)1/2). Nearly similar patterns were detected on frequency distribution of fertile leaves, fertility increase and number of leaves in threeDryopteris ferns which exhibit funnel-shaped foliage arrangements in mature sporophyte. No difference was found in number of leaves, maximum NV, fertility rate and leaf-shape parameters among three ferns. A positive difference was found only on changes in order of pinnae with maximum number of costa branches (NVP) and the DI of outline of pinnae betweenD. crassirhizoma andD. filix-mas. These allopatricDryopteris ferns seem to have a similar foliage structure, in spite of some sympatricDryopteris ferns capable of producing putative hybrids (D. austriaca andD. amurensis; D. tokyoensis andD. monticola) having different foliage structures in Hokkaido. Contribution No. 3346 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

2.
An intra-species comparison of the life history of various populations ofPolystichum tripteron was undertaken in Hokkaido and Honshu in Japan with respect to some leaf-size characters and fertility during sporophyte development. The developmental process of sporophytes was quantitatively estimated by counting the number of venation (NV: number of midrib branches of the leaf). The mean NV of the fertile leaves decreased slightly with increasing altitude on Mt. Teine near Sapporo and with increasing latitudes from Honshu to Hokkaido. The blade length was longer at any NV in Hokkaido populations than in those of southern Honshu. Longer blade (BL) and pinna length (PL) and lesser number of pinnules of the lowest pinna (NPLP) versus NV were observed in leaf populations from Hokkaido than in those from southern Honshu. The maximum values of lowest pinna length (LPL), NV, number of costa branches (NVLP) and number of pinnule (NPLP) were larger in southern Honshu than in Hokkaido. In the course of leaf-shape formation represented by the ratio of PL to BL versus NV, the Kyoto population seemed to be more differentiated into long-lanceolate fronds than did the Hokkaido population. Initiation of fertility in the sporophyte development and the maximum NV seemed to decrease with increasing altitudes and latitudes in Japan. Contribution No. 2885 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

3.
The foliage development ofDryopteris crassirhizoma Nakai was quantitatively estimated by measurements of shape and size of leaves from different developmental stages of sporophytes, to lead to an understanding of the life history characteristics of the species. The number of midrib branches (NV, number of veins) of the leaf corresponds to the leaf-shape complexity (DI, dissection index; shape complexity from a circle) and length of leafblade (BL). Some quantitative characters, such as leaf uniformity (decrease in NV variation), changes in shape and increase in number of leaves, vary progressively during foliage formation. The sequence of foliage development can be quantified using the parameter NV: for example, 15-NV for leaf uniformity, 30-NV for leaf-shape change from triangular to oblanceolate, 60-NV for increase in leaf number and leaf fertility in the course of sporophyte ontogeny. Contribution No. 3297 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

4.
To understand the life history characteristic for expanding the distributional area to colder climates, developmental age structure of population ofCyrtomium falcatum was observed along southwestern coasts of Hokkaido at the natural northern boundary of its distribution, with reference to the alternation of generations. The length and number of pinna of fertile leaves ofCyrtomium falcatum decrease towards the northern part of Japan. In southwestern Hokkaido, typically dwarf fertile leaves and gametophytes were observed growing together on cliffs nearby the sea. To estimate the developmental ages of small and dwarf leaves, the number of venation (NV: branching number of vein from midrib) of leaves was counted on each sporophyte. The sporophyte with leaves at the simple pinna stage ranging from 0–25NV, is predominant in the population of southwestern coasts of Hokkaido. The fertility of the sporophyte seems to be achieved more than five years after the germination. The gametophytes were also observed at the location to be almost equal in number to sporophytes. The number of gametophytes and sporophytes decreases with advancement of developmental stages. In the same location at Okushiri Isl. with slight gradiency of humidity, the gametophyte is predominant on the drier cliff, while the sporophyte is predominant on the humid hole. The population ofCyrtomium falcatum at the natural northern boundary in Hokkaido, seems to have the life history characteristic with alternation of generations. Contribution No. 2557 from the Inst. of Low Temp. Sci.  相似文献   

5.
To elucidate the quantitative and qualitative expression of fern development, various features of leaf-size and morphology were examined on leaves ofPolystichum tripteron (Aspidiaceae) in Japan. Among ten parameters, the number of branches of the leaf midrib (NV) proved to be the most successful for discrimination between fertile and sterile leaf populations. In the phase-change from sterile to fertile leaves, the NV parameter also gave the strongest correlation, increasing with fertility (r = 0.983), and is therefore a useful tool for research into the life history characteristics of ferns.Contribution no. 2751 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

6.
The temperate fernsPolystichum craspedosorum, P. retroso-paleaceum, P. tripteron, P. braunii andP. microchlamys are distributed widely in Hokkaido: on 13 Hokkaido mountains their average altitudinal distributions are 450, 479, 570, 689 and 964 m above sea level, respectively. The developmental stage of the sporophytic leaf is expressed by the “number of venation” (NV, the number of veins branching from the midrib of the leaf), which, inPolystichum ferns, is itself a qualitative expression of the phase-change from sterile to fertile leaf production and is more discriminatory than leaf area, length or dry weight. Usually, the developmental stage structure of the fertile leaf expressed by NV in the fivePolystichum ferns showed a normal distribution. Among the fourPolystichum ferns that grow in the forest understory of Hokkaido's cool temperate regions, a good correlation was found between the mean altitude of vertical distribution and the maximum NV of the leaf (r=−0.993) and the initiation of maturity in the relative developmental stage (r=0.991) of the ferns.Polystichum craspedosorum found on cliffs, however, matures at much earlier stage and has the smallest maximum NV. In the developmental stage expressed by the NV, the initiation of fertility and maximum NV seem to be correlated with altitudinal distribution and habitat in populations ofPolystichum ferns in Hokkaido. Contribution No. 2694 from the Inst. of Low Temp. Sci., Hokkaido University.  相似文献   

7.
Genetic differentiation of the two sibling species,Cottus nozawae andC. amblystomopsis, from the northern part of Japan (Hokkaido Island and the Tohoku District) was investigated using allozyme variations and restriction fragment length polymorphisms of mitochondrial DNA. Although the two species are morphologically very similar, previously being thought to be a single species, they have different life-cycles;C. nozawae has a fluvial life-cycle with a small number of large-sized eggs, whereasC. amblystomopsis is an amphidromous species with a large number of small-sized eggs. Four populations ofC. amblystomopsis from Hokkaido Island and 24 populations ofC. nozawae (22 from Hokkaido Island and 2 from the Tohoku District) were sampled and examined Intrapopulational differentiation in the two species was measured by examining several indexes, including proportion of polymorphic loci (P), mean heterozygosity (H) and nucleotide diversity (π). All measurements were higher in theC. amblystomopsis populations, suggesting that intrapopulational variation inC. nozawae was less than inC. amblystomopsis and reflecting the difference in effective population sizes between them. Cluster analyses were performed using the UPGMA method, based on the data matrices of genetic distance (D) and the net nucleotide difference (δ) between populations. TheC. nozawae andC. amblystomopsis populations from Hokkaido Island composed a large cluster (Hokkaido group), while theC. nozawae populations from the Tohoku District composed a different cluster (Tohoku group). Bootstrap probabilities deduced from 1000 bootstrap replications for presence or absence of restriction sites showed that the mtDNA haplotypes detected within the Tohoku Group occurred in 99.9% of the bootstrap replicates outside the mtDNA haplotypes of the Hokkaido group, while those within the Hokkaido group occurred in 3.5–64.9% of bootstrap replicates. Consequently, the Hokkaido populations of the two species (Hokkaido group) were genetically close to each other, whileC. nozawae from the Tohoku District (Tohoku group) were distant from the Hokkaido group. These results suggest that the ancestral populations of the two species on Hokkaido Island shared the same gene pool, even after becoming geographically isolated from the ancestral population ofC. nozawae in the Tohoku District by the formation of the Tsugaru Straits.  相似文献   

8.
To elucidate the life cycle time schedule of semi-evergreen ferns at natural sites in Sapporo, the chronological age for sporophyte maturation was estimated from the increase in the number of veins (NV, number of midrib branches) from overwintered to newly expanded leaves. The measurements were conducted on populations ofPolystichum braunii, Polystichum tripteron andDryopteris crassirhizoma at altitudes of 50–650 m on Mt. Teine to compare the interspecific maturation age of sporophytes. The mean age for sporophyte maturation was estimated to be 7.6 yr forP. braunii, 16.5 yr forP. tripteron and 12.6 yr forD. crassirhizoma. The minimum ages (1% fertility rate) for sporophyte maturation ofP. braunii, P. tripteron andD. crassirhizoma were 5.8, 11.0 and 7.9 yr, respectively. The maturation age was shortest forP. braunii and longest forP. tripteron. The maturation age of a species thus seems to differ according to altitude and habitat, and that of the present three species seems to be influenced by the geographical location of the species distribution. Contribution No. 3315 from the Institute of Low Temperature Science, Hokkaido University.  相似文献   

9.
Androecial development of 13 species belonging to six tribes ofFlacourtiaceae has been investigated. While inScolopieae andFlacourtieae the stamens develop centrifugally, inErythrospermeae, Oncobeae andPangieae they are initiated in a centripetal sequence or a sequence that is neither distinctly centripetal nor centrifugal. The distribution of these developmental patterns coincides with the distribution of other characters (e.g. cyanogenic compounds, salicoid leaf teeth) and therefore supports a split of the family intoFlacourtiaceae s. str. (containing theScolopieae, Homalieae, Prockieae, Flacourtieae, Casearieae andBembicieae) andKiggelariaceae (withErythrospermeae, Oncobeae andPangieae) and is in accordance with results of recentrbcL studies.  相似文献   

10.
A chemotaxonomic study of practically all the species of the genusAloe showed that flavonoids occur as major compounds in 31 out of a total of 380 species investigated. Flavanones and dihydroflavonols are present in the exudate of species inAloe ser.Rhodacanthae andSuperpositae and also in a number of the endemic species from Madagascar. Flavones occur as the only major compound in the leaf extracts of the sects.Leptoaloe andGraminialoe. In ser.Macrifoliae and inLomatophyllum, the sister genus ofAloe, isovitexin co-occurred with theC-glucosylanthrone aloin. The chemotaxonomic implication of these results are discussed together with the significance of the taxonomic and chemogeographical distribution of flavonoids inAloe. With a few rare exceptions, the leaf compounds from two different biogenetic pathways (polyketide pathway and flavonoid pathway) are mutually exclusive. Since flavonoids are restricted to the basal groups inAloe, we conclude that flavonoids are plesiomorphic characters inAloe reflecting ancient phylogenetic and biogeographic links.  相似文献   

11.
据已有文献记载,香姜(姜科)(Alpinia coriandriodora D. Fang)仅分布于广西,现首次在越南发现其分布。该种在形态上与竹叶山姜(A. bambusifolia D. Fang)相近,但其叶片椭圆状披针形、唇瓣浅黄色及带红褐色条纹和花药附属体三角状而与后者有别。提供该种详细的形态学描述以及图版,亦包括在越南的分布及生态的资料。凭证标本保存于越南国立自然博物馆(VNMN)和中国科学院华南植物园(IBSC)。  相似文献   

12.
Paraveinal mesophyll (PVM) is a distinctive anatomical feature of the leaf mesophyll of some plant taxa that may represent a specialized physiological compartment. A comprehensive review of the 42 published references that mention PVM or similar cell layers and a survey of 121 of the 272 species of all nine genera of thePhaseoleae subtribeErythrininae demonstrate that PVM is nearly exclusively found inLeguminosae. InLeguminosae, PVM is either rare or absent in subfamilyCaesalpinioideae, uncommon inMimosoideae, and extensively distributed amongPapilionoideae. In subtribeErythrininae, PVM is ubiquitous inErythrina, and occurs in four other genera. ThreeErythrininae genera (Apios, Mucuna, andCochlianthus) lack PVM. Unique chloroplast-poor, enlarged conical cells (pellucid palisade idioblasts) occur in 80 species ofErythrina but not in any other genus ofErythrininae.  相似文献   

13.
Chromosome counts are presented for 12 genera and 20 species of AustralianAnnonaceae (all diploid with 2n = 16 or 18; Table 1) and two species ofEupomatiaceae (2n = 20, partly from Papua New Guinea). Detailed studies on interphase nuclear structure, condensing behaviour of chromosomes, and fluorochrome and Giemsa C-banding patterns also includeHimantandraceae (Galbulimima) andAustrobaileyaceae. — Eupomatiaceae completely correspond withAnnonaceae karyologically, their base number 2n = 20 is interpreted to have evolved from 2n = 18 by ascending dysploidy from common ancestors.Eupomatia laurina andE. benettii differ in DNA and constitutive heterochromatin (hc) quantity; their evolution from high to low DNA content probably corresponds to general progressions inMagnoliidae. Austrobaileya has nuclei of the presumably primitive Tetrameranthus type which is closely related to that ofGalbulimima and several other primitive taxa inMagnoliidae. Karyomorphology and other characters support the maintainance of two main branches within theMagnoliidae, Laurales andMagnoliales, withAustrobaileya probably intermediate; theWinteraceae appear more remote.—InAnnonaceae the reestablishment ofAncana is underlined by its chromosome number (2n = 18) the unexpected and specialized disulcate pollen, and various morphological characters which point to a close alliance with the Australian endemic generaFitzalania andHaplostichanthus (also disulcate) and the American genus pairSapranthus/Desmopsis; they are united in the provisionalSapranthus tribe, with a more distant position toFissistigma s. str. (2n = 16). AustralianAnnonaceae exhibit a high generic and a low species diversity; they can be considered as an ± old and partly impoverished outpost of the family with phytogeographical relationships to Asia, Africa and America.—On the base of field observations three main types of floral development inAnnonaceae are proposed, the most elaborated one found in the fly pollinated genusPseuduvaria. The growth form change from shrubs to lianas during the ontogeny ofDesmos andMelodorum, the vegetative propagation of anAncana species and the ecological and evolutionary patterns of the taxa investigated are discussed.  相似文献   

14.
Summary The morphopalynological cards ofThuja orientalis L. and ofCryptomeria japonica (L. fil.) D. Don were illustrated as part of a more comprehensive study on ornamental Pinophyta. Pollens from the original area of the two species were also compared with grains coming from plants cultivated in Italy. In the case ofCryptomeria japonica (L. fil.) D. Don DV, D01, D02, exine, min. and max. diameters, calculated on a japanese sample, differed significatively from the italian sample. In the case ofThuja orientalis L. no significant differences were observed. Pollen from the two italian sites did not show significative differences in size and shape. Pollens acetolysed with the traditional method (Erdtman, 1960) were compared with pollens treated with the Tatzreiter method (1985). Morphometric analysis showed similar values for both species.  相似文献   

15.
A new leaf blight and mummy fruit disease caused by a species of Monilinia was first found on Rhododendron kaempferi at the lakeside of Shikotsu-ko, Hokkaido, northern Japan, in 2002. Studies on morphology, life cycle, cultural characters, and gene analyses of the causal fungus enabled us to conclude that it is a new species of the genus. It is named M. jezoensis. Rhododendron is a new host genus for Monilinia fungi in Japan.  相似文献   

16.
Seasonal courses of leaf CO2 gas exchange in a growing season were examined in saplings ofThujopsis dolabrata var.hondai andQuercus mongolica var.grosseserrata in a cool temperate deciduous forest. Between the two tree species there were no large differences in the light compensation point of leaf photosynthesis, except for the season of new leaf expansion. However, light-saturated rates of net photosynthesis were obviously high inT. dolabrata var.hondai. EvergreenT. dolabrata var.hondai saplings had large photosynthetic production in two seasons, before the emergence of new foliage and after foliage fall of the overstory deciduous trees, because of the significantly high solar radiant energy penetrating under the forest canopy during the seasons. Saplings of deciduousQ. mongolica var.grosseserrata were heavily shaded throughout the growing season by foliage of the overstory trees, which resulted in a low daily surplus production. The annual surplus production of leaves in the growing season was estimated to be 2300 mmol CO2 m−2 inT. dolabrata var.hondai and −100 mmol CO2 m−2, slightly negative, inQ. mongolica var.grosseserrata. These results supported the high survivability ofT. dolabrata var.hondai saplings and the high mortality ofQ. mongolica var.grosseserrata in the deciduous forest.  相似文献   

17.
The flowers ofDillenia are highly elaborate pollen-flowers adapted to buzzpollination byXylocopa bees. Two major forms of floral architecture (revolver flowers and roundabout flowers) are associated with two different pollination modes. In the first (e.g.,D. suffruticosa), the pollination organs are connivent to a cone; the pollinator grasps the entire cone with its legs and buzzes it; it revolves around its axis and repeats the buzzing in different positions. In the second (e.g.,D. alata, D. philippinensis), the stylar branches are spreading and the stamens are arranged in two sets of two different forms and colourations. The inner set has fewer and longer stamens that are cryptic pollination stamens; those of the outer set are shorter but optically conspicuous feeding stamens. The pollinator squeezes itself under the stylar branches and handles only the outer set by grasping part of the set at a time; it moves tangentially around the flower with several buzzing-stops; when buzzing pollen is sprayed onto its side and back from the inner stamen set. Centrifugal polyandrous androecia are a constitutive feature of flowers inDilleniaceae. InDillenia the centrifugal initiation of stamens proceeds for an unusually long time and is still not finished when the gynoecium is completely closed (in contrast toTetracera). The differentiation of heteranthery seems to be functionally correlated with the extended centrifugal inception. The latest formed stamens are small and sterile in many species. Generic features ofDillenia flowers can be understood from the roundabout architecture: big size, increased number of carpels, syncarpy forming a firm pedestal and spreading firm stylar branches with small, concave stigmas at the end, stamens with short, stout filaments and much elongated poricidal anthers, heteranthery, recurved stamens of the inner set.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

18.
Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJe, Je, JeJb, and Jb can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.  相似文献   

19.
Phyllotaxis and vascular course in the vegetative shoots ofRubia akane andR. sikkimensis were studied. Each node of both species has a whorl of four leafy members among which two are true leaves. Arrangement of the true leaves is not decussate but bijugate, i.e., opposite leaves are arranged spirally. Bijugy was ascertained not only by gross morphology but also by arrangement of primordia around the shoot apex and vascular course through several internodes. Divergence angle differed widely with internodes even within a single shoot and with shoots even in the internodes which are separated by a same number of nodes from the apex. Mean divergence angles obtained for five youngest internodes of some shoots were between 49.4° and 61.8° inR. akane and between 53.6° and 59.4° inR. sikkimensis. Young seedlings ofR. akane showed decussate phyllotaxis in the lowermost several internodes. In the internodes near the lower end of the bijugate part, the divergence angle was wider than in the upper internodes. The directions of the phyllotactic spirals in the main axis and the lateral branches were either homodromous or antidromous, and those in the oppositely paired branches also were either homo- or antidromous.  相似文献   

20.
Crown architecture was analyzed forScaphium macropodum (Sterculiaceae), a common shade-tolerant emergent tree of a tropical rain forest in West Kalimantan, Indonesia. Saplings and poles shorter than 12 m in height had no branches, and gathered their leaves at the ends of the stem. The leaves changed from entire to palmately-parted with increasing tree size. The parted leaves increased the light penetration through the clustered foliage. The size of leaves including the blade and petiole ranged from 22 cm to 147 cm. Because the weight of petiole per blade increased with leaf size, the leaf could not be enlarged infinitely. Taller trees with lateral branches bore small (about 40 cm in length) entire leaves. The light intensity in the forest increased from the ground to about 12 m tall and was nearly constant from 12 m to 18 m. Crown architecture ofS. macropodum adapted to this light environment. The monoaxial trees lower than 12 m could thus increase the amount of light with vertical elongation, and the branched trees higher than 12 m could increase it by means of lateral extension of crown area.  相似文献   

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