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1.
Ten taxa of the genusPisum were examined by disc electrophoresis in gels according to Davis and to Reisfeldet al. For evaluation of band patterns the Jaccard Index was applied. The results in both types of gels show thatPisum abyssinicum and especiallyP. fulvum have biochemically a relatively isolated position.Pisum elatius and its subspeciescaspicum andpalestinicum form a subgroup withP. cinereum;P. sativum var.zeylanicum and cv. Jupiter form another subgroup withP. syriacum. Our results are in good agreement with the results of Przybylskaet al. (with the exception ofP. cinereum) and also with immunoelectrophoretic analyses performed by Turkováet al. (1980), with the same exception.  相似文献   

2.
The genusLens includes 5 taxonomic species:L. culinaris is cultivated andL. orientalis, L. odemensis, L. ervoides, andL. nigricans are wild. All the species are annual and almost exlusively selfers. The wild lentils are distributed over a large geographical area and form small disjunct populations which are composed of a small number of plants. 67Lens populations were assayed electrophoretically for 9 enzyme systems; 15 enzymic genes with 37 alleles were identified. The genetic distances (D) measured between the pairs of populations indicated a significantly greater similarity between populations belonging to the same taxonomic species. Assuming the populations represent a random sample of the variability in each of the species the genetic distances (D) between the 5 taxa were calculated. The shortest genetic distance was found betweenL. orientalis andL. culinaris. Another significant feature of the data is the apparent isolation ofL. nigricans from the other 4 species. The genetic distances between theLens species are compared to the patterns of crossability barriers between them.  相似文献   

3.
Nucleotide sequences of the small-subunit (SSU) ribosomal DNA were determined forPelvetia babingtonii, P. canaliculate, Pelvetiopsis limitata, andAscophyllum nodosum in the family Fucaceae. A total of 1755 positions were aligned for the whole sequence. The positional differences in the primary structure among the taxa ranged from 16 to 30 nucleotide changes in pairwise comparisons. There was a minimum divergence betweenPs. limitata andP. babingtonii while a maximum betweenPs. limitata andP. canaliculata. The SSU rDNA trees showed that the genusPelvetia was not monophyletic and the genusPelvetiopsis was not closely related toPelvetia. Our results suggest that the taxonomic revision of the genusPelvetia as well as the family Fucaceae is needed based on detailed morphological observations.  相似文献   

4.
Pinus krempfii is morphologically very unique as compared to otherPinus species by having flat leaf-like needles. Its taxonomic position has been problematic ever since its discovery. In this study, an attempt was made to infer the taxonomic status ofP. krempfii through restriction fragment length polymorphism analysis of 12 PCR amplified chloroplast (cp) DNA regions. Phylogenetic analysis was conducted using 10 representatives of the twoPinus subgenera:Strobus andPinus. In addition, to infer the position ofP. krempfii in Pinaceae in relation with other genera, 14 representatives of eight additional genera were included in the analysis. Our cpDNA-based results indicate that: 1)P. krempfii clearly belongs to the genusPinus. This result does not favour the creation of a new genusDucampopinus in Pinaceae for this taxon. 2) Within the genusPinus, P. krempfii is more allied with species in subgenusStrobus and differs distinctly from species in subgenusPinus. 3) Despite the similarity in certain morphological and anatomical leaf and wood characters toKeteleeria andPseudolarix, the cpDNA data do not support the hypothesis for close relationship betweenP. krempfii and these two genera.  相似文献   

5.
6.
Electrophoretic studies on seed storage proteins of various gymnosperm species showed that both salt soluble and insoluble protein fractions give taxonomic information. Among species of the genusPinus evident differences are found between the subgeneraHaploxylon (Strobus) andDiploxylon (Pinus). In sect.Strobus the two subsectt.Strobi andCembrae are readily distinguished fromP. bungeana (sect.Parrya) which appears to fall in an intermediate position between haploxyl and diploxyl pines. Among the species of subg.Diploxylon, mountain pines show very similar protein patterns in agreement with their recent speciation (Quaternary).  相似文献   

7.
The genusPlectranthus (Lamiaceae) shows remarkable radiation on the sandstones of southern Natal and northern Transkei in South Africa, where six endemic species occur. Two of these endemic species,P. hilliardiae andP. oribiensis, are included in this study, as well asP. reflexus, for which only limited data are available. The other species that were studied areP. ambiguus, P. ciliatus, P. ecklonii, P. madagascariensis andP. zuluensis. Four of these taxa,P. ambiguus, P. hilliardiae, P. reflexus andP. saccatus var.longitubus, have uniquely long corolla-tubes (20–30mm) and this is related to pollination by nemestrinid flies of the genusStenobasipteron that have proboscides of similar length. Other nemestrinid species of the genusProsoeca have shorter proboscides and pollinate two species ofPlectranthus with shorter corolla-tube lengths (6–15mm). Acrocerid flies, tabanid flies and anthophorid bees are also important visitors to these species. This study on the pollination of seven species of varying corolla-tube lengths shows a correlation between floral tube length and proboscis length of insect visitors, many of which are recorded for the first time as pollinators ofPlectranthus.  相似文献   

8.
The early anthropoid species initially described asAegyptopithecus zeuxis Simons, 1965, from the Oligocene of Egypt, although retained by many authors in the monotypic genusAegyptopithecus, has been lumped by others into the genusPropliopithecus. Similarly, the species originally described asParapithecus grangeri Simons, 1974, has been ranked by some authors in a monotypic genusSimonsius, while others retain it inParapithecus. Criteria to be considered in resolving these taxonomic debates are (1) the adequacy and consistency of proposed morphological differences between species; (2) analogy with the degree of morphological variation tolerated within extant genera; and (3) nomenclatural conservatism. A philosophy that would require strict monophyletic classification is of insufficient practical value for assessing the validity of Fayum genera. Characters cited as distinguishing vetweenAegyptopithecus andPropliopithecus, and betweenSimonsius andParapithecus, are reviewed and evaluated. The results indicate thatA. zeuxis is generically distinct from species ofPropliopithecus, based on differences in the crown structure and proportions of the molars.Pa. grangeri cannot be shown to differ at the generic level from the type and only known specimen ofPa. fraasi, thus establishing Simonsius as a junior synonym ofParapithecus.  相似文献   

9.
The sexual speciesSporidiobolus salmonicolor andSporidiobolus pararoseus spp. nov. are described as heterothallic species in the genusSporidiobolus, a genus consisting of two homothallic species,Sporidiobolus johnsonii andSporidiobolus ruinenii. The four species are compared and a key to the genus is presented. As a taxonomic correctionSporobolomyces pararoseus nom. nud. is reported as a synonym ofSporobolomyces shibatanus.  相似文献   

10.
Acyrthosiphon pisum is a polyphagous aphid of major importance on the pea crop to which few resistant cultivars are available. In this study, we screened a germplasm collection of Pisum spp. under field conditions over two seasons yielding the identification of a number of accessions with intermediate levels of resistance. Selected accessions were further studied under semi‐controlled and controlled conditions in no choice and choice assays to validate the responses, and to further characterise the mechanisms of resistance operative. Results elucidated the valuable resistance of accession P40 (Pisum sativum ssp. sativum) and P665 (P. sativum ssp. syriacum), with the combination of both antixenosis, by reducing aphid preference, and antibiosis, by diminishing aphid proliferation.  相似文献   

11.
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   

12.
Examination of thin sections ofMicrococcus diversus, Neisseria catarrhalis andN. sicca reveals a cytoplasmic membrane, nuclear region and ribosomes which correspond to those recognized in other bacteria. Their cell walls are multilayered and resemble those of gram-negative microorganisms. Structures suggestive of mesosomes were observed inM. diversus andN. catarrhalis. These cytological observations concur with the findings of Kocur for the fine structure ofMicrococcus denitrificans andM. halodenitrificans. The taxonomic position of the problematic species in the genusMicrococcus is discussed.This study was supported by a grant from United States Department of Agriculture (USDA) Forest Service 4000, Grant 1.  相似文献   

13.
A taxonomic study of the genusDelilia is presented. Two species are recognized:D. biflora, a widespread weed of tropical and subtropical regions of the New World, extending from Mexico to northern Argentina and recently introduced in the Cape Verde Islands; andD. repens, endemic to the Galapagos islands. A key to the species, illustrations, distribution maps, and complete synonymy are presented.  相似文献   

14.
Origanum (Lamiaceae) comprises a number of essential oil‐rich species that have been used by humans for centuries. Today, the four species of section Majorana (O. onites, O. dubium, O. majorana and O. syriacum) are amongst the most widely used. Despite the importance of this section, phylogenetic relationships and species boundaries amongst its four taxa are unclear. In the present investigation, we used DNA sequence data from two nuclear regions [internal transcribed spacer (ITS) and 1‐deoxy‐d ‐xylulose 5‐phosphate synthase (DXS)] as well as five microsatellite loci to test the taxonomic status of the four species of section Majorana. The combined DNA data revealed O. onites and O. syriacum as the older species in the section. Origanum majorana descends directly from O. syriacum. Origanum dubium was found to be of hybridogenous origin showing attributes of O. onites, O. syriacum and a third, unknown, Origanum species. Both sequence and microsatellite analyses provided evidence for recent hybridization between O. onites and O. dubium in Turkey. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013 , 171 , 667–686.  相似文献   

15.
Summary A taxonomic study of the members of the family Choanephoraceae was undertaken. Almost all the species of the family have been isolated from various sources in India. Two genera, viz.,Blakeslea andChoanephora have been recognized and a key to the genera has been given. The genusBlakeslea includes only one speciesB. trispora and the genusChoanephora five species. A key to the species has also been given. A new variety ofChoanephora circinans, viz.,C. circinans var.prolifera Mehrotra andMehrotra based on the proliferating vesicular apices of the sporangiophores has been described.  相似文献   

16.
Seed storage proteins have proved to be a powerful biochemical marker for taxonomic research, but they have not been extensively employed in forest tree studies. In order to improve the understanding of the taxonomy of the genusPinus, total seed proteins of 12 pine species have been analyzed by means of SDS-PAGE (Sodium dodecylsulphate-polyacrylamide gel electrophoresis). The results showed the presence, in the genusPinus, of two main sub-taxa, corresponding to the subgeneraHaploxylon andDiploxylon. Differences and affinities between Mediterranean pine species were found in agreement with classification ofKlaus (1989).  相似文献   

17.
Two new Brazilian species of the genusHuberia,H. carvalhoi andH. consimilis, are described, discussed, and illustrated.Huberia carvalhoi is endemic to Bahia;H. consimilis has a wider distribution, with disjunct populations in Pernambuco, Bahia, and Rio de Janeiro. A key is provided to the three Bahia taxa with some comments on the taxonomic affinities of the two new species.  相似文献   

18.
A taxonomic revision of the Nematotaeniidae, involving the examination of over 400 specimens, was undertaken. Some new taxonomic characters have been introduced to allow distinction of the various species. The family contains 18 recognized species in four genera. The genusNematotaenia Lühe, 1910 contains four species, namelyN. chantalae Dollfus, 1957,N. dispar (Goeze, 1782) Lühe, 1910,N. hylae Hickman, 1960, andN. tarentolae Lopez-Neyra, 1944.N. kashmirensis Fotedar, 1966,N. dollfusi, Yuen & Fernando, 1974 andN. viride Mokhtar-Maamouri & Chakroun, 1984 are considered junior synonyms ofN. dispar. N. aurangabadensis Chincholikar & Shinde, 1975,N. lopezneyrai Soler, 1945 andN. mabuiae Shinde, 1968 are consideredspecies inquirendae: the latter species probably belongs in the genusOochoristica Lühe, 1898 (Anoplocephalidae: Linstowiinae). The genusCylindrotaenia Jewell, 1916 is shown to possess two testes per segment and not one as originally proposed:Baerietta Hsü, 1935 is consequently synonymized withCylindrotaenia. Cylindrotaenia is divided into five species-groups on the basis of adult morphology. The first group contains two American species, namelyC. americana Jewell, 1916 andC. idahoensis (Waitz & Mehra, 1961) n. comb. The second group contains species from Australia and New Zealand, namelyC. allisonae (Schmidt, 1980), n. comb.,C. criniae (Hickman, 1960) n. comb.,C. decidua (Ainsworth, 1985) n. comb.,C. hickmani (Jones, 1985) n. comb. andC. minor (Hickman, 1960) n. comb. A third species group consists ofC. jaegerskioeldi (Janicki, 1926) n. comb.,C. magna n. sp. andC. philauti Crusz & Sanmugasunderam, 1971 and occurs in Africa, Sri Lanka and Japan. The fourth group, apparently restricted to Japan, contains a single species,C. japonica (Yamaguti, 1938) n. comb. The fifth group containsC. montana (Yamaguti, 1954) n. comb. and occurs in Japan and Tibet.C. quadrijugosa Lawler, 1939 is synonymized withC. americana, andBaerietta claviformis Yamaguti, 1954 is synonymized withC. japonica. C. baeri (Hsü, 1935) n. comb.,C. chilensis (Puga & Franjola, 1983) n. comb.,C. diana (Helfer, 1948) Lehmann, 1960,C. malayi (Yuen & Fernando, 1974) n. comb. andC. roonwali Nama, 1972 arespecies inquirendae. The genusDistoichometra, Dickey 1921 contains a single species, namelyD. bufonis Dickey, 1921.D. kozloffi Douglas, 1958 andBaerietta enteraneides (Helfer, 1948) Yamaguti, 1959 are reduced to synonymy withD. bufonis. Bitegmen n. g. is proposed to accomodate a single species,B. gerrhonoti (Telford, 1965) n. comb., which was previously included in the genusBaerietta. The present distribution of the Nematotaeniidae is largely related to that of their anuran hosts. Nematotaeniids probably arose in Gondwanaland.  相似文献   

19.
A study was made of the genetic variability of 101 barley populations belonging to the four, wild, Spanish species of the genusHordeum (the autogamousH. marinum subspp.marinum andgussoneanum, andH. murinum subspp.murinum andleporinum, plus the allogamous speciesH. bulbosum andH. secalinum). Electrophoresis of endosperm proteins was performed using a large number of individuals from each population sampled, in order to determine intra- and interpopulational variation. The distribution of variability observed by population and taxonomic unit, is closely related to the breeding system.Hordeum bulbosum showed the greatest intrapopulational variability andH. marinum subsp.gussoneanum the least. In contrast to the autogamous species, the allogamous species showed low levels of interpopulational variation.  相似文献   

20.
The relationship between the generaHansenula andPichia was examined through comparisons of DNA relatedness among phenotypically similar species.Hansenula minuta andPichia lindneri showed 75% DNA base sequence complementarity. In other comparisons,H. nonfermentans was found to share nearly 50% of its DNA sequences with bothH. minuta andP. lindneri. Because of the high degree of relatedness observed, it is proposed that ability to assimilate nitrate, the sole distinction betweenHansenula andPichia, is of insufficient taxonomic value for the reliable separation of either species or genera. Hat-spored species ofHansenula H. et P. Sydow 1919 are being transferred toPichia Hansen 1904. Species ofHansenula andPichia with Saturn-shaped ascospores will be transferred to the genusWilliopsis. The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

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