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1.
The 16 species of theSedum acre-group were investigated for the presence of alkaloids. They areS. acre ofS. ser.Acria, S. alpestre, S. annuum, S. apoleipon, S. borissovae, S. euxinum, S. grisebachii, S. laconicum, S. multiceps, S. sexangulare, S. tuberiferum, S. tuberosum, S. ursi, andS. urvillei ofS. ser.Alpestria, S. samium ofS. ser.Samia, andS. litoreum ofS. ser.Litorea. S. acre differs significantly from the other species. It contains sedamine, hydroxy sedamine, and a number of 2,6-disubstituted piperidine alkaloids. The leafy parts of the species ofS. ser.Alpestria, S. ser.Samia, andS. ser.Litorea contain 4 piperidine alkaloids which also occur inS. acre, and in addition 4 pyrrolidine alkaloids not present inS. acre. The composition of the alkaloid fraction agrees with the infrageneric classification (series) based on the hybridization patterns of the species (comparia).  相似文献   

2.
The distribution of excreted flavonoid aglycones within the familyLabiatae was studied and differences were found, especially in the A-ring substitution patterns. Thus, 5,7-dihydroxy-6-methoxyflavones with substituted B-rings are characteristic of species ofSalvia (sect.Salvia),Rosmarinus andOcimum; 5,7-dihydroxy-6,8-dimethoxyflavones occur only inOcimum and 5,6-dihydroxy-7,8-dimethoxyflavones inThymus and related species. Members of the two subfamiliesLamioideae andNepetoideae produce exudate flavonoids, but some genera are devoid of these compounds. There is a correlation between the habitat where the plant grows and production of these compounds, the species from (semi-)arid habitats being those which generally accumulate external flavonoids.  相似文献   

3.
A preliminary account of Entolomataceae from Costa Rica is presented. Three new taxa are described, two inClitopilus, one inRhodocybe, and three new combinations are proposed inInocephalus. Five taxa ofClitopilus are reported for the first time from Costa Rica and a key to species is provided. Four species ofRhodocybe are discussed and a key to the six species known from Costa Rica is also provided.Alboleptonia earlei, Inocephalus murraii, Inocephalus quadratum, Rhodocybe incarnata andRhodocybe pseudonitellina are now known to occur in Costa Rica.  相似文献   

4.
Fungal endophytes occurring in leaves and stems of three species of Proteaceae,Protea cynaroides, Leucospermum cordifolium andLeucadendron salignum×laureolum were investigated on farms in three locations in the Western Cape province of South Africa. The aims of this study were to determine ifBotryosphaeria proteae, a fungus that has been recorded from leaf spots ofProtea spp., was mostly restricted to leaf tissue, and whether it could occur as an endophyte in different members of Proteaceae. In this studyB. proteae was routinely isolated inProtea andLeucospermum, although it was not a dominant taxon and did not occur inLeucadendron. Botryosphaeria proteae occurred mostly in leaves, rather than stems, suggesting that it is not important as a stem canker pathogen.  相似文献   

5.
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   

6.
The subdivision of theAnthemideae into two subtribes purely on the grounds of the presence or absence of receptacular paleae can no longer be maintained. Anatomical data may serve as a basis for a more adequate division of the tribe. This survey of the stomatal apparatus types within theAnthemideae is based on the investigation of 29 species from 15 genera and the evaluation of literature data: Anomocytic stomatal apparatus occur in all species examined, anisocytic at least in all genera investigated by us. We even found representatives of some rare types, such as polo-, helico- or hemiparacytic apparatus, in nearly all species. Diacytic types were not found inOtanthus, Artemisia, Tripleurospermum, Tanacetum corymbosum, and they also appear to be lacking inSantolina andEriocephalus. Paracytic stomatal apparatus and a new type which links paracytic with actinocytic and cyclocytic was discovered inOtanthus maritimus andArtemisia stellerana.
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7.
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   

8.
Both adaxial and abaxial leaf surfaces were searched for stomata inBalanophora elongata, B. fungosa, Hachettea austro-caledonica, Langsdorffia hypogaea, Lophophytum mirabile subsp.mirabile, Scybalium jamaicense, andThonningia sanguinea (Balanophoraceae). Neither stomata nor guard cells were observed. The epidermal surfaces of these species are extremely diverse with respect to cell shape, cell size, and surface ornamentation, these features providing valuable systematic criteria.  相似文献   

9.
In a chemotaxonomic study of the genusSymphytum pyrrolizidine alkaloids and triterpenes were used as chemotaxonomical markers. A micro-extraction methods was developed for screening compounds of very small pieces of herbarium material. The occurrence of the pyrrolizidine alkaloids symphytine and (acetyl-)lycopsamine is very general forSymphytum taxa. Echimidine is present in someS. officinale L. plants and inS. tanaicense Steven. The triterpene isobauerenol is present inS. officinale, S. bohemicum Schmidt,S. tanaicense and inS. officinale var.lanceolatum Weinm. The chemotaxonomic hypothesis, proposed byGadella and collaborators, based on the presence of the triterpene isobauerenol inS. officinale and its absence inS. asperum Lepech. and the presence of the pyrrolizidine alkaloid echimidine inS. asperum and its absence inS. officinale, can no longer be applied absolutely to theS. officinale species complex. The pyrrolizidine alkaloid and triterpene pattern ofS. officinale (2n = 24) andS. bohemicum (2n = 24) is identical.S. bohemicum is morphologically, cytologically and phytochemically very similar toS. officinale. Furthermore, it readily crosses with the white flowered W. European diploids ofS. officinale. Therefore it seems likely that these two taxa are conspecific.S. tanaicense shows a pyrrolizidine alkaloid and triterpene pattern similar toS. officinale (2n = 40). Also on morphological and cytological grounds they are very similar. It seems highly probable thatS. tanaicense is conspecific withS. officinale (2n = 40) and represents an intraspecific variant only.S. officinale var.lanceolatum contained no pyrrolizidine alkaloids but did contain isobauerenol. This feature points to an origin fromS. officinale.  相似文献   

10.
Three new species of Myrtaceae (Calyptranthes bracteata, Eugenia gonglycocarpa, andMyrcia rupta) from northeastern South America are described and illustrated, and a new combination (Eugenia tetramera) is proposed. The closed-calyx and the completely or partially fused cotyledons ofMyrcia rupta, unusual features for the genus, are discussed and compared with related species inMyrcia andMarlierea.  相似文献   

11.
Sequence data from internal transcribed spacer (ITS) regions of rDNA and data from morphology, cytology and wood anatomy are used to study phylogenetic relationships inPseudopanax. The molecular and non-molecular data are analysed as independent data sets and in combination using parsimony. Results supported the conclusion that the genusPseudopanax is polyphyletic.Pseudopanax species emerge in two major monophyletic groups. The Anomalus group containsPseudopanax anomalus, P. edgerleyi, andP. simplex; these species share a common ancestor withCheirodendron trigynum and more distantly withPseudopanax gunnii. The second major group consists of two smaller groups: the Arboreus group, includingPseudopanax arboreus, P. colensoi, P. kermadecensis, P. laetus, andP. macintyrei, and the Crassifolius/Discolor group, includingP. chathamicus, P. crassifolius, P. discolor, P. ferox, P. gilliesii, P. lessonii, andP. linearis. Meryta species are close relatives of thePseudopanax Arboreus and Crassifolius/Discolor groups.  相似文献   

12.
A study of the phenolic compounds of the closely related papilionoid tribes,Podalyrieae andLiparieae, proved that the flavonoid patterns of hydrolysed seed extracts are remarkably conservative. Butin (7, 3, 4-trihydroxyflavanone), 3-hydroxydaidzein (7, 3, 4-trihydroxyisoflavone), vicenin-2 (6, 8-di--D-glucopyranosyl-5, 7, 4-trihydroxyflavone) and orobol (5, 7, 3, 4-tetrahydroxyisoflavone) were isolated and identified as the major flavonoids. The seeds ofAmphithalea, Coelidium, Liparia, Xiphotheca, Calpurnia, Stirtonanthus andPodalyria accumulated three isoflavone O-glycosides that yielded 3-hydroxydaidzein on hydrolysis. In contrast,Virgilia contained a unique combination of vicenin-2 and orobol. Vicenin-2 was also present inCalpurnia as a major compound, butStirtonanthus insignis was the only other species studied that contained orobol (in trace amounts only). Butein, a chalcone, was reported byHarborne from the seed ofCyclopia subternata. This compound's flavanone analog, butin, was the principal component inCyclopia. A cladistic analysis, using flavonoid, alkaloid and morphological data, showed that the seed flavonoids of thePodalyrieae andLiparieae behave rather poorly as cladistic characters. They are, however, of considerable taxonomic value at the tribal level favouring the opinion that the two tribes should be combined. The apparent absence of flavonoids in the seed ofHypocalyptus supports the suggestion that it should be excluded from theLiparieae. Flavonoids also show that theArgyrolobium-group is very different from the tribeCrotalarieae and support the recent transfer of this group to the tribeGenisteae.  相似文献   

13.
A comparative study of 20 blood genetic systems was performed on three populations of genusSaguinus: S. fuscicollis weddelli, S. midas niger, andS. midas midas. Some markers are useful for the characterization of the two species.ADA 5, ADA6, CA23, CA24, andES2 2 occur only inS. fuscicollis whileADA 4is fixed inS. midas. S. midas midas showed heterozygosity value comparable to those previously obtained for the genusAlouatta. Estimates of genetic distance betweenS. fuscicollis andS. midas species of about 14% are in accordance with those referred to in the literature for interspecific differences. Genetic distances between subspecies ofSaguinus midas were nearly 3%, which is within the range for subspecies.  相似文献   

14.
The chemosystematic value of UV-absorbing leaf constituents was considered in previously uncharacterised representatives of Aloe section Pictae, the problematic maculate species complex. Comparative data indicate that the anthrone C-glycoside, 6′-malonylnataloin (7-hydroxychrysaloin 6′-O-malonate) is typical of maculate species in East Africa, but is unconvincing as a synapomorphy for section Pictae. A naphthalene derivative found widely in Aloe, plicataloside, was detected in Aloe greatheadii. Biogeographical trends were observed in the occurrence of the flavonoids isoorientin (luteolin-6-C-glucoside) and isovitexin (apigenin 6-C-glucoside). Isoorientin is a common constituent of tropical and sub-tropical species of Aloe, whereas isovitexin is restricted to a few southern African species. Isoorientin and isovitexin co-occur in the southern African maculate species Aloe parvibracteata, and the disjunct West African maculate species, Aloe macrocarpa. This is the first report of isoorientin and isovitexin in maculate species of Aloe; the presence of flavonoids in section Pictae is of taxonomic interest.  相似文献   

15.
Based on collectors' measurements of 1,040 specimens, variation of relative tail length [RTL = (tail length/head and body length) × 100] has been studied inMacaca fascicularis andM. mulatta, two closely related species that replace one another in tropical Asia and subtropical Asia, respectively. RTL usually is greater than 90 inM. fascicularis and usually is less than 60 inM. mulatta; intermediate values occur in only 3.5% of specimens studied. Within each species, RTL is approximately equal in females and males. From infancy to adulthood, RTL tends to decline in both species. InM. fascicularis, RTL generally decreases with increasing latitude; inM. mulatta, RTL is approximately constant latitudinally. Where the geographic ranges of these two species meet at ca. 15°N in the Indochinese Peninsula, a few specimens have been collected in which RTL and dorsal pelage color are intermediate between those inM. fascicularis andM. mulatta. The observed pattern of variation suggests that the ranges ofM. fascicularis andM. mulatta formerly were separated by a zoogeographic barrier — perhaps during a Pleistocene glacial interval. After disappearance of the postulated barrier, the ranges of these two species apparently became contiguous and limited hybridization has occurred.  相似文献   

16.
In situ hybridization with a biotin-labeled rice ribosomal DNA (rDNA) probe to the somatic metaphase chromosomes of six species ofPhaseolus andVigna (P. angularis, P. calcaratus, P. coccineus, P. vulgaris, V. sesquipedalis andV. sinensis) was done to determine the sites of rDNA. Hybridization signals were present in the terminal and subterminal chromosome regions of each of the six species. The number of rDNA sites was two inP. angularis andP. calcaratus, four inP. coccineus andP. vulgaris, and six inV. sesquipedalis andV. sinensis.  相似文献   

17.
Hyphomorpha, a genus of theStigonematales, is confirmed to be a phycobiont in twoSpilonema species (Coccocarpiaceae). The morphology of the symbiotic algae inSpilonema dendroides andS. schmidtii is described. The phycobiont inS. dendroides is possiblyHyphomorpha antillarum, the alga inS. schmidtii might be a species related toH. perrieri. New localities for the rare lichens are reported: Alaska forS. dendroides and Ceylon forS. schmidtii.
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18.
The subfamilyPhytelephantoideae comprises three genera (Ammandra, Aphandra, andPhytelephas) and seven species of dioecious palms. The floral scents ofAmmandra dasyneura, A. decasperma, Aphandra natalia, Phytelephas aequatorialis, P. macrocarpa, andP. seemannii were analyzed by gas chromatography-mass spectrometry. We studied the pollination biology ofA. natalia, P. aequatorialis, andP. macrocarpa, and tested how the synthetically produced main constituents of the floral scents ofAphandra andPhytelephas attracted insects in two natural populations ofPhytelephas. The genera are distinct in terms of floral scents.Ammandra has sesquiterpenes,Aphandra (+)-2-methoxy-3-sec-butylpyrazine, andPhytelephas p-methyl anisol. These constituents dominated the scents quantitatively and qualitatively. The similarity between scents of male and female inflorescences was 76.5% inAmmandra, 84.2% inAphandra, and >99% inPhytelephas. Different species ofAleocharinae (Staphylinidae) pollinateAphandra natalia andPhytelephas species and reproduce in their male inflorescences.Derelomini (Curculinoidae) andMystrops (Nitidulidae) only visit and pollinatePhytelephas in which male inflorescences they reproduce. A species ofBaridinae (Curculionidae) only visits and pollinatesAphandra natalia, and reproduces in its female inflorescence. The apparent reliance on one or a few floral scent constituents as attractants and few and specific pollinators may indicate co-evolution. Sympatric species ofPhytelephantoideae have different scents. We suggest that species with similar scents have allopatric distributions due to the absence of a pollinator isolation mechanism.  相似文献   

19.
The effects of 4 or 8 drought cycles on four grass species,Cenchrus pennisetiformis, Leptochloa fusca, Panicum turgidum, andPennisetum divisum were assessed in a pot experiment. There were significant differences between the species in biomass production under water stress.C. pennisetiformis andP. turgidum produced significantly greater fresh and dry matter thanP. divisum and especially thanL. fusca. L. fusca had the lowest andP. divisum highest osmotic potentials compared with the other species after the completion of 4 or 8 drought cycles. Osmotic adjustment (difference between osmotic potential of droughted/rehydrated plants and control plants) was highest inL. fusca. The stomatal conductance was significantly decreased with increased drought stress inC. pennisetiformis. The elasticity ofC. pennisetiformis, P. turgidum andP. divisum increased with increase in number of drought cycles, whereas that ofL. fusca remained unchanged.L. fusca andP. turgidum had the lowest leaf hydration of all species after 8 drought cycles. The chlorophyllsa andb in all species remained unaffected by drought treatments. The proline content ofC. pennisetiformis andL. fusca increased significantly with increased drought stress, whereas that ofP. turgidum remained unaffected after 4 or 8 drought cycles.L. fusca synthesized great amount of leaf soluble proteins during 8 drought cycles, whereasP. divisum had low protein content after 4 drought cycles. The protein contents ofC. pennisetiformis andP. turgidum remained unaffected after 8 drought cycles. The leaf epicuticular wax ofL. fusca increased consistently with increased drought stress, but leaf wax ofP. divisum increased only at the highest drought stress and that ofC. pennisetiformis andP. turgidum increased after 4 drought cycles. On the basis of these results it was established thatC. pennisetiformis andP. turgidum were the most tolerant,P. divisum intermediate, andL. fusca the most sensitive to drought stress. The osmotic adjustment did not positively correlate with the degree of drought resistance.  相似文献   

20.
The stelar structure ofAsplenium obtusifolium and its related species (A. repandulum, A. riparium, A. triquetrum, A. volubile, A. purpurascens, A. ortegae, A. delitescens, A. hoffmannii, andA. laetum) in the New World tropics was observed and compared to that of Asian species ofAsplenium sect.Hymenasplenium. Both of the groups were found to share peculiar stelar structures: steles with two meristeles, a broader ventral and a narrower dorsal, each providing one of the two leaf traces; leaf gaps arranged in two rows between the dorsal and ventral strands, which are connected by thin meristeles, delimiting the leaf gaps. These structures are distinct from the radial symmetrical ones general inAsplenium. Together with cytological evidence, this strongly indicates that the New and Old World groups are closely related. Thus, these Neotropical species should be included in sect.Hymenasplenium.  相似文献   

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