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1.
The region of Iran, Iraq, Afghanistan and the neighbouring countries is important for some groups of the speciesLotus L., especially those of the circle ofL. corniculatus L. andL. gebelia Vent. The first group is represented by the speciesL. corniculatus L. with 4 subspecies (3 of which are important for this region), andL. tenuis Waldst. etKit. which here attains the eastern boundary of the continuous area of distribution, and by the eastern speciesL. krylovii Schischk. etSerg. andL. rechingeri Chrtková-?ertová. The second group is represented by the speciesL. gebelia Vent.,L. michauxianus Ser. in DC. andL. libanoticus Boiss. their areas of distribution covering mostly those regions. Most of the species show considerable variability within the species.  相似文献   

2.
Mitochondrial DNA (mtDNA) variation among specimens of the northwestern African hare (Lepus capensis schlumbergeri) and three European hares sampled in Spain (L. castroviejoi andL. granatensis, which are endemic to the Iberian Peninsula, andL. europaeus) was analyzed using seven restriction endonucleases. Fourteen haplotypes were found among the 34 animals examined. Restriction site maps were constructed and the phylogeny of the haplotypes was inferred. mtDNA ofL. capensis was the most divergent, which is consistent with its allopatric African distribution and with an African origin of European hares. We estimated that mtDNA in hares diverges at a rate of 1.5–1.8% per MY assuming that the European and African populations separated 5–6 MYBP. Maximum intraspecies nucleotide divergences were 1.3% inL. capensis, 2.7% inL. castroviejoi, and 2.3% inL. granatensis but 13.0% inL. europaeus. The latter species contained two main mtDNA lineages, one on the branch leading toL. castroviejoi and the other on that leading toL. granatensis. The separation of these two lineages from theL. castroviejoi orL. granatensis lineages appears to be much older than the first paleontological record ofL. europaeus in the Iberian peninsula. This suggests that the apparent polyphyly ofL. europaeus is due not to secondary introgression, but to the retention of ancestral polymorphism inL. europaeus. The results suggest thatL. europaeus either has evolved as a very large population for a long time or has been fractionated. Such a pattern of persistence of very divergent lineages has also been reported in other species of highly mobile terrestrial mammals. As far as mtDNA is concerned,L. europaeus appears to be the common phylogenetic trunk which has diversified during dispersion over the European continent and from whichL. castroviejoi andL. granatensis speciated separately in southwest Europe.  相似文献   

3.
Five new species and two varieties from the sectionMultifidae are described from the Sino-Himalayan region. They are referred to the affinity ofP. multifida L. andP. griffithii Hook. f.; one of the new species is probably related toP. gerardiana Lindl. and one is intermediate between the species of the sectionsMultifidae andNiveae.  相似文献   

4.
Nigerian species ofPortulaca: P. grandiflora Hooker,P. oleracea L. andP. quadrifida L. combine inbreeding, outbreeding and vegetative propagation in the wild and in the oultivation. Observations have shown that the anthers ofPortulaca species dehisces before the flower bud opens, and are usually ripe at the time the stigmas are receptive. This enhances self-fertilization.  相似文献   

5.
6.
Chloris barbata Sw. andCyperus rotundus L. from a mercury contaminated site near a chloralkali plant were tested for relative tolerance to Hg by root-elongation method. The above two species from the Hg-contaminated site exhibited high tolerance to Hg compared to the same species from a non-contaminated site. Tolerance to Hg was higher inChloris barbata than inCyperus rotundus.  相似文献   

7.
8.
Okoli B. E. etNyananyo B. L. (1988): Palynology ofTelfairia L. (Cucurbitaceae).—Folia Geobot. Phytotax., Praha, 23: 281–283.—Scanning and transmission electron microscopic studies were carried out on the pollen of the two species ofTelfairia, T. pedata (Sims.) Hooker andT. occidentolis Hooker fil. Pollen grains in both species are spheroidal, tricolporate and tectate. The extexine is finely reticulate. The tectum, foot layer and columellae are all well developed. Significant differences of taxonomic value do not exist in the structure of the pollen of the two species.  相似文献   

9.
Recent ethnographic research carried out in Spain has allowed the cultivation ofLathyrus sativus L. andL. cicera L. to be documented. Both species already appear in the Spanish archaeological record. Grown under traditional farming systems,L. sativus L. andL. cicera L. are still used for human consumption (onlyL. sativus L.) and both are used for fodder. Data on cultivation history, fanning practices, crop processing sequence and uses are here presented, which will enable a better understanding of their possible roles in prehistoric times.  相似文献   

10.
The present paper deals with cytotaxonomy ofChelidonium majus L. s. 1. taxa and their hybrids. Based on results of hybridization experiments, cytology and reproductive isolation, a new combination,Ch. asiaticum (Hara) Krahulcová, is proposed. The structure of the aggregate is as follows:Ch. majus L. subsp.Majus (2n=12, distributed in Europe),Ch. majus L. subsp.grandiflorum (DC.)Printz (2n=12, S. Siberia, China) andCh. asisaticum (2n=10, E. Asia). Karyotypes ofCh. m. subsp.grandiflorum andCh. asiaticum are compared in detail.  相似文献   

11.
Width-to-length ratios of upper stem leaves ofLasallea novaeangliae andL. oblongifolia were determined from herbarium specimens and field collections. No distinct subgroups based on suchratios were found in either species. InL. novaeangliae the curve of the ratio versus number of individuals was skewed toward the narrow-leaf range. This phenomenon was present but less pronounced inL. oblongifolia. The histogram of leaf ratios forL. novaeangliae was somewhat weakly bimodal, suggesting a possible broad-leaf race, which has not been recognized nomenclaturally. The absence of bimodality in the histogram of leaf ratios forL. oblongifolia indicates the need to place Shinners’ narrow-leaved varietyangustatus in synonymy. Other traits such as height, degree of branching and the nature of the pubescence were also found to be of no significance. Slight geographic trends in leaf width occur in both species. No real evidence was found for nomenclaturally recognizing any eastern variant in either species. Thus, Shinners’ var.orientis is not recognized inL. oblongifolia either.  相似文献   

12.
13.
Lopholejeunea subgenusPteryganthus is described as new based upon the Mauritian plantL. sphaerophora (Lehm. & Lindenb.) Steph.Lopholejeunea utriculata Steph. from Madagascar is included as well.Lopholejeunea sinuata (Mitt.) Steph. is reduced to synonymy withL. sphaerophora. The two species of subgenusPteryganthus are compared withL. herzogiana Verd. andL. pullei Verd., two Malaysian species, with superficially similar lobule construction, but not of thePteryanthus type.  相似文献   

14.
The present paper describes the comparative biochemical studies in terms of quantitative analyses of carbohydrates, lipids, proteins, free amino acids, nucleic acids, minerals, ash and moisture as well as the identification of free amino acids of pollen of four species ofCassia L. (C. alata L,C. fistula L,C. occidentalis L andC. siamea Lam.). A significant variation in the chemical constituents was observed among the four species.C. occidentalis showed the highest levels of carbohydrate (15.15%) and protein (22.45%), andC. siamea had the lowest levels of carbohydrate (7.15%), lipid (6.2%) and protein (13.85%).C. alata andC. fistula showed intermediate results. However,C. alata showed the highest amount of free amino acids (3.8%) and the least of 1.42% was found inC. fistula. Thin layer chromatography (TLC) of free amino acids of the four species showed some homology in their amino acid content, of which proline, glutamic acid, methionine and phenyl-alanine were the most dominant. The level of nucleic acids and minerals was found to be comparatively low.C. siamea andC. alata showed an exceptionally high level of ash content (8.6 and 8.8%, respectively) while moisture content varied from 8 to 11%.  相似文献   

15.
J. L. Hemptinne 《BioControl》1988,33(4):505-515
During 3 successive winters, we studied the dormancy sites ofPropylea quatuordecimpunctata (L.) andCoccinella septempunctata L., 2 species of ladybirds which hibernate in leaf litter. Samples of litter were taken from several kinds of forest to study the influence of 3 variables (exposure; altitude; sampling place: edge or inner wood) on the abundance of ladybirds. We found the ecological requirements of the 2 species of coccinellids to be quite different:C. septempunctata prefers forest edges orientated towards the South and the West.P. quatuordecimpunctata prefers the inner wood and does not show a preference for station exposure. For each species, the number of ladybirds collected in the samples is positively correlated with station altitude. In addition, some observations were carried out to examine the main mortality factors just before and during dormancy. In maize fields near dormancy sites, the harvest is very harmful forC. septempunctata. During the winter,P. quatuordecimpunctata andC. septempunctata suffer fromBeauveria ssp. and some ladybirds have parasitoïds.  相似文献   

16.
A history is presented of the use and misuse of the binomials,Rumex maritimus andR. persicarioides. In light of single-character separation of the taxa, an alternative to current taxonomic usage is proposed. This treatment recognizes one species (R. maritimus, by prior choice) with two New World varieties. One change in status is made.  相似文献   

17.
Morphological variation ofPotentilla norvegica L.,P. heidenreichii Zimmeter andP. supina L. usually treated within the sectionRivales Wolf,P. recta L. (sect.Rectae Wolf),P. canescens Bess.,P. argentea L. s.l.,P. collina Wibel (sect.Argenteae Wolf) andP. goldbachii Rupr. (sect.Chrysanthae Wolf) was studied using multivariate statistical methods. According to k-means clustering,P. canescens stands closer toP. heidenreichii of the sect.Rivales than toP. argentea. P. collina, the other representative of sect.Argenteae, is not connected withP. canescens at all. Therefore,P. canescens should belong to sect.Rivales and not to sect.Argenteae. InPotentilla argentea s.l.,P. impolita Wahlenb.,P. argentea L. var.argentea, var.decumbens (Jord.)Lehm., var.demissa (Jord.) Lehm., var.grandiceps (Zimmeter) Rouy etE.G. Camus and var.tenerrima (Velen.) Wolf were identified.P. impolita specimens did not cluster out into a separate cluster as didP. collina, P. canescens andP. heidenreichii, but formed mixed clusters with different varieties ofP. argentea s.str. Therefore,P. impolita is not worthy of the rank of species and evidently not even that of subspecies, and should be treated as a variety—P. argentea var.incanescens (Opiz) Focke.  相似文献   

18.
The fungal colonization of the angiosperm root parasiteCynomorium coccineum and the halophytic hostsLimonium delicatulum andArthrocnemum glaucum were investigated in a Mediterranean salt marsh in March 1992. The main fungal inhabitants on the leaves or shoot surface of the test plants wereAspergillus niger, Penicillium chrysogenum andCladosporium herbarum. The qualitative analysis of the fungal species associating the parasite, the hosts and the non-infected plants showed similar pattern. However, the total population exhibited quantitative differences coupled with the amount and the chemical composition of the exudates on plant surface and the quantity of transpired water. The fungal catch from the aerial shoot (inflorescence) of the parasite was higher than that collected from either the leaves or aerial shoots of non-infected or host plants. The fungal density on the leaves ofL. delicatulum was higher than those isolated from the aerial shoots ofA. glaucum. Infection byC. coccineum caused a marked drop in the total fungal population on leaves or shoot surfaces of the hosts as compared to the corresponding non-infected individuals. The stimulative effect of washings on spore germination of some isolated fungal species was matched with the density of fungi on the target plants.  相似文献   

19.
20.
Clarifying interspecific differences in prey items in relation to morphological characteristics is a fundamental aspect to understand the mechanism enabling the diversity of feeding ecology of fishes. The aim of the present study was to clarify the relationship between prey items and body shape variation, teeth and mandible characteristics for four lutjanid species: Lutjanus decussatus, L. fulviflamma, L. fulvus and L. gibbus. Stomach contents analysis revealed that the main prey items of L. decussatus were fishes, L. fulviflamma were crabs and fishes, and L. fulvus and L. gibbus was crabs. Body shape analysis revealed that L. decussatus and L. fulviflamma had a shallower body depth whereas L. fulvus and L. gibbus had a deeper body depth. The two species with a shallower body had long teeth whereas the other two species with a deeper body depth had shorter teeth. The jaw-lever mechanics were compared and L. decussatus and L. fulviflamma have a faster mouth opening–closing mechanism. Canonical correspondence analysis revealed that fishes was the major prey item for the species having a shallower body depth, higher teeth length and lower ratios of in-lever to out-lever of mandibles, whereas crabs was the major prey item for the species having a deeper body depth, lower teeth length and higher ratios of in-lever to out-lever of mandibles. It is suggested that the interspecific differences in main prey items among the four species are directly related to behavioral differences based on body shape, teeth characteristics and jaw-lever mechanics.  相似文献   

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