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1.
Reexamination ofXanthoria persica, X. polycarpoides, X. lobulata gave evidence, that the thalli of these species are devoid of a lower cortex and rhizinae. Therefore, they do not fit the
definition of the genusXanthoria and are transferred toCaloplaca (under the new sectionXanthoriella) asCaloplaca persica, C. polycarpoides, andC. boulyi, respectively. — Details on development, anatomical structure, ecology and distribution are presented.
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2.
The genetic relationships of the Hawaiian endemic genus Lipochaeta and the nearly cosmopolitan but extra-Hawaiian genus Wedelia were assessed by way of experimental hybridization. Hybrids between Wedelia biflora and diploid species of Lipochaeta consistently exhibited 15 pairs of chromosomes at meiosis, whereas the modal and maximum configuration seen in hybrids between W. biflora and tetraploid species of Lipochaeta was 15II + 11I. Meiotic pairing in microsporocytes of the intergeneric hybrid combinations involving Wedelia trilobata and both sections of Lipochaeta is lower than in intergeneric hybrids involving W. biflora. All of the intergeneric F, hybrids produced had relatively low pollen stainabilities ranging from less than 1–16% and, although they were vegetatively vigorous, they failed to produce viable achenes. The effects of chromosome doubling by colchicine in one species and several hybrids in Lipochaeta and in one intergeneric hybrid between Lipochaeta and Wedelia were studied. Chromosome doubling of the diploid species caused a decrease in pollen stainability and resulted in lack of achene production, whereas doubling the chromosomes of sterile intersectional and intergeneric hybrids restored female fertility and effected a dramatic increase in pollen stainability. Cytological analysis of the microsporocytes at diakinesis and metaphase I revealed pairs and quadrivalents in the induced polyploids. Pollen measurements indicated that pollen size in Lipochaeta is correlated with doubling of the chromosomes. Statistical analyses revealed that there is no significant difference in pollen size between the diploids and natural tetraploids, whereas both groups have pollen grains that are significantly smaller than the induced autotetraploid, the intergeneric allotetraploid, and the intersectional allohexaploid. The cytogenetic evidence indicates a relatively close genetic relationship between Wedelia and Lipochaeta and supports the view that the ancestry of the diploid section Aphanopappus of Lipochaeta (n = 15) is to be found in a species akin to Wedelia biflora (n = 15) and that this or a similar 15-paired wedelioid species and an unknown 11-paired wedelioid taxon are involved in the alloploid hybrid origin of the tetraploid section Lipochaeta (n = 26) of Lipochaeta. 相似文献
3.
Thomas Mione 《Brittonia》1999,51(1):31-33
The following species, originally described in the genusSaracha Ruiz & Pav., are transferred toJaltomata, in accordance with contemporary generic boundaries.Jaltomata auriculata (Miers) Mione is distributed from Venezuela to Peru;J. contorta (Ruiz & Pav.) Mione andJ. diversa (J. F. Macbr.) Mione both occur in Peru;J. herrerae (C. V. Morton) Mione is distributed in Peru and Bolivia;J. nitida (Bitter) Mione occurs in Venezuela. 相似文献
4.
5.
The leaf-anatomy, palynology, seed-morphology, vegetative morphology and especially the highly complicated floral morphology of theCoryciinae s. str. (Diseae: Orchidoideae: Orchidaceae) are described and illustrated in detail. On the basis of these characters the presumed phylogeny, based on a rigorous cladistic analysis, is presented. The cladistic biogeographical analysis of theCoryciinae s. str. shows that it is a member of the Afrotemperate Track, with a pattern of vicariance events typical of the members of this track. An analysis of the patterns of speciation shows that allopatric speciation appears to be rare, and that parapatric speciation across edaphic boundaries may be the most important factor. Proceeding from the information presented, a new classification of the group is proposed in which we recognize the four generaCeratandra, Evotella, Pterygodium andCorycium. The new monotypic genusEvotella comprises a species originally described asPterygodium rubiginosum. The three species of the genusAnochilus are transferred toCorycium andPterygodium. P. magnum, which was originally described asPterygodium but was transferred toCorycium lately, is placed in a monotypic section ofPterygodium. 相似文献
6.
Jose M. Bonifacino 《Brittonia》2008,60(3):205-212
Nardophyllum armatum, a species from the Puna region of Argentina, Bolivia, and Chile is here transferred to genus Ocyroe, which in turn is resurrected from the synonymy under Nardophyllum. Ocyroe is characterized by thorny branches, discoid capitula, naked receptacles, glandular corollas with a globose swelling at the
base, and a profuse 3- to 5-seriate pappus. The new combination Ocyroe armata and a lectotype for Dolichogyne armata are here presented. 相似文献
7.
Alfonso Susanna Teresa Garnatje Núria Garcia-Jacas 《Plant Systematics and Evolution》1999,214(1-4):147-160
The genusCheirolophus has an interesting western Mediterranean and Macaronesian distribution. Here we investigate the delimitation of the genus and its exclusion from the large genusCentaurea, the systematic position of the related genusPaleocyanus, the delimitation of some species and the phylogeny of the group. We have carried out a phylogenetic analysis of the PCR-generated sequences of the internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA. The results suggest that the genus, includingPaleocyanus crassifolius is monophyletic; thus, a new combination of this species underCheirolophus is proposed. The Macaronesian group of species is also monophyletic, indicating a single colonization of the archipelago. The poor resolution of microspecies in the Macaronesian group reinforces the hypothesis of a very recent differentiation of the group. 相似文献
8.
Yuri A. Popov 《Pal?ontologische Zeitschrift》2007,81(4):429-439
Mainly based on collections from Willershausen (Lower Saxony, North Germany), the Pliocene Heteroptera fauna of West Europe
is briefly revised. The present compilation includes a checklist with taxonomic and systematic corrections ofJordan’s (1967, 1969) type materials. Naucoroid water bugs of the family Aphelocheiridae are distinguished and the extinct species
of the genusAphelocheirus are redescribed. The new genusWillershausenia n.gen. (type species:Nabis strausi
Jordan, 1969) is defined and transferred to the coreoid family Alydidae.
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9.
Wenyan Wang Chenggang Wang Bang-Lian Huang Bangquan Huang 《Plant Cell, Tissue and Organ Culture》2008,92(2):165-171
A protocol was developed for regeneration and Agrobacterium-mediated genetic transformation of Lesquerella fendleri. Calli were first induced from hypocotyls and cotyledons on MS plus 0.5 mg l−1 BA, 1 mg l−1 NAA and 1 mg l−1 2,4-D, then co-cultivated for 2–3 days in darkness on MS supplemented with 0.5 mg l−1 BA, 0.2 mg l−1 NAA and 100 μmol l−1As together with Agrobacterium tumefaciens strain EHA105/pCAMBIA1301 that harbored genes for uidA (GUS) and hygromycin resistance. Following co-cultivation, calli transfected by A. tumefaciens were transferred to MS with 0.5 mg l−1 BA, 0.2 mg l−1NAA, 500 mg l−1 Cef and 10 mg l−1 hygromycin and cultured for 10 days, then the hygromycin was increased to 20 mg l−1 on the same medium. After 4 weeks the resistant regenerants were transferred to MS with 0.5 mg l−1BA, 0.2 mg l−1 NAA, 500 mg l−1 Cef and 25 mg l−1 hygromycin for further selections. Transgenic plants were confirmed by polymerase chain reaction analysis, GUS histochemical
assay and genomic Southern blot hybridization. With this approach, the average regeneration frequency from transfected calli
was 22.70%, and the number of regenerated shoots per callus was 6–13. Overall results described in this study demonstrate
that Agrobacterium-mediated transformation is a promising approach for improvement of this Lesquerella species. 相似文献
10.
Comparative capitular morphology and anatomy of Coreopsis L. and bidens L. (compositae), including a review of generic boundaries 总被引:1,自引:0,他引:1
The capitular and floral morphology and anatomy ofBidens L. andCoreopsis L. were studied. All the North American species ofCoreopsis were studied. Selected species ofBidens from North and South America andCoreopsis from South America were included. The results were compared with previous observations on African species ofBidens (incl.Coreopsis). Emphasis was given to character states of the ray florets, paleae, stylearm apices, outer phyllaries, achenes, and pollen
grains. Some of the character states are unique features ofCoreopsis, e.g., globular and elongately conical receptacles, deltoid outer phyllaries, truncate and indistinctly 3–5-dentate, 3–4-lobed
ray florets, narrowly spathulate paleae, subulate paleae with linear-filiform upper half, hairy and apically 3-cleft paleae,
truncate, convex or shallowly conical stylearm apices with the sweeping hairs limited to the area above the stigmatic surfaces
and the orbicular to circular achenes. The cylindric setaceous pappus bristles so commonly encountered inBidens are unknown inCoreopsis. The pappus bristles inCoreopsis are paleaceous but similar, though thicker ones are also found in African species ofBidens (incl.Coreopsis) with winged achenes. Twin-celled hairs (setulae) with differing degrees of wall thickness are found on the achenes ofCoreopsis sect.Pseudoagarista (Mexico and South America),Coreopsis sect.Pugiopappus (California), AfricanBidens with winged achenes (e.g.,B. prestinaria, B. macroptera) and some North AmericanBidens (e.g.,B. aristosa). Similar sclerotic parenchyma make up the achenial wings of species in both genera. These may be interpreted as homologous
structures, indicating the underlying similarity of these taxa and their derivation from a common ancestral stock. 相似文献
11.
Ellis L. Yochelson 《Pal?ontologische Zeitschrift》2002,76(2):297-304
Dentalium antiquum is one of two moderately well-known Devonian “scaphopods” in the German literature. Examination of the type material and
a few specimens in other institutions indicates more individual variability than is to be expected in species of the molluscan
class Scaphopoda. The species is transferred with question toColeolus
Hall, a fossil presumed to be a calcareous “worm” tube.
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12.
All North American annual species of the genusMicroseris have a five-part pappus, the one South American annual,M. pygmaea, has ten pappus parts. The pappus develops over a constant number of ten provascular bundles with or without inhibition between alternate sites of pappus development. Each natural population contains a predictable proportion of achenes with aberrant pappus part numbers. Hybridization betweenM. bigelovii (5 parts) andM. pygmaea results in F 1 and F 2 plants with many aberrant achenes. In each plant either five or ten can be shown to be the basic number with aberrant numbers following a Poisson distribution for numbers added to 5 or deleted from 10. Occasional plants show no basic number but have a random distribution of numbers about an intermediate mean. The evolutionary genetics of this character is discussed. 相似文献
13.
Vishwanath M. Patil 《In vitro cellular & developmental biology. Plant》1998,34(3):240-243
Summary The purpose of this study was to developin vitro techniques for conserving wild and endemic species ofCeropegia by mass multiplication for subsequent reintroduction in their natural habitat. Micropropagation involving a combination of
axillary bud culture, shoot multiplication, somatic embryogenesis andin vitro tuber formation forCeropegia jainii, a rare plant of the Indian sub continent,C. bulbosa var.bulbosa andC. bulbosa var.lushii, common species, was developed. Nodal explants from all species were cultured on 0.5 MS medium with 8.8 μM (2 mg·l−1) N6-benzyl aminopurine (BA) to regenerate the axillary buds. These produced multiple shoots when transferred to multiplication
medium consisting of 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA, or microtubers when transferred to 0.5 MS medium with 22.2 μM (5 mg·l−1) BA and 23.2 μM (5 mg·l−1) kinetin.In vitro flowering occurred inC. jainii and not in the other two varieties when the plants were cultured on multiplication media with spermine at 0.25 μM (50 μg·l−1) as an additive. Shoot pieces produced callus on MS medium with 9.05 μM (2 mg·l−1) 2,4-dichlorophenoxy acetic acid. Regeneration of the calli by somatic embryogenesis was achieved when they were transferred
to 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA. Rooting of the shoots was possible both byin vitro andex vitro means. 相似文献
14.
Anthostomella graminella has been re-examined and ascomata were found to be immersed beneath a clypeus. Asci were unitunicate, broad cylindrical,
and lacked an apical apparatus, while ascospores were inequilaterally ellipsoidal, 1–2 seriate, brown to light brown and unicellular,
with bipolar germ pores. Based on these characters,A. graminella is transferred toPandanicola. An illustration of this species and a tabulated comparison of this species withPandanicola calocarpa is given. 相似文献
15.
N. M. Solov'eva M. G. Pimenov M. G. Vasil'eva N. N. Žigareva V. D. Turkov 《Plant Systematics and Evolution》1985,151(1-2):89-101
A study of morphometric karyotype characters was carried out in 14 species ofPeucedanum s. lat. (Umbelliferae — Apioideae) and in one species of the related genusLomatium. The differences of the species in their karyotype characters are correlated only to a limited degree with their similarities
of dissimilarities in morphological (i. a. carpological) characters, and thus with their taxonomic position. The evolution
of these two sets of characters seems to have proceeded not synchronously or even in different directions in the group of
platycarpousUmbelliferae united in the genusPeucedanum. Therefore, it is unlikely that morphometric chromosome characters revealed by monochrome staining can be used appropriately
in the taxonomic revision of the polymorphous genusPeucedanum. 相似文献
16.
Ma Dolores Lledó Manuel B. Crespo Juan Bta Amo-Marco 《In vitro cellular & developmental biology. Plant》1995,31(4):199-201
Summary
Vella lucentina M. B. Crespo is a threatened Spanish species that is endemic to a small area in eastern Alicante Province (SE Spain). Micropropagation
techniques were applied forex situ conservation of this plant. Aseptic epicotyls bearing the apical bud were grown in Murashige and Skoog medium supplemented
with 6-furfurylaminopurine (Kin), N6-benzyladenine (BA) or 6-(γ,γ,-dimethilalylamino) purine (2iP). High multiplication rates were obtained with 0.5, 1, or 2
mg·liter−1 BA, or 1 or 2 mg·liter−1 2iP. Indole-3-acetic acid and indole-3-butyric acid were utilized for rooting in half-strength Murashige and Skoog medium.
Regenerated plants were transferred to a potting mix and gradually acclimated to field conditions. No morphological differences
were observed amongin vitro andin vivo plants. 相似文献
17.
Summary
Leptadenia reticulata (Retz.) Wight. & Arn., an important herbal medicinal plant, belongs to the family Asclepiadaceae. This plant has been known
for its medicinal uses since 4500 BC. Presently this is an endangered species. There is a need for applying non-conventional
methods of propagation for conservation and sustainable utilization of biodiversity of Leptadenia reticulata. We developed a micropropagation method for mass multiplication of L. reticulata. Explants harvested from greenhouse-maintained and field-grown plants were used to establish cultures of L. reticulata. The nodal shoot segments were surface-sterilized and cultured on Murashige and Skoog (MS) medium along with additives (25
mg l−1 each of adenine sulfate, arginine, and citric acid, and 50 mg l−1 ascorbic acid) containing 0.6 μM indole-3-acetic acid (IAA) and 9 μM N6-benzyladenine (BA). Three to four shoots differentiated from each node within 25–30 d at 26±2°C and 36 μmol m−2 s−1 spectral flux photon (SFP) for 12 hd−1. Shoots were further multiplied by (1) repeated transfer of mother explant on fresh medium containing 0.6 μM IAA and 2.2 μM BA, and (2) subculture of in vitro-differentiated shoots on MS medium with 6.6 μM BA and 0.6 μM IAA. After three or four subcultures, the basal clump with shoot bases was divided into three or four subclumps and multiplied
on the fresh medium. From each clump 15–20 shoots regenerated within 25 d. Ninety percent of the in vitro-produced shoots rooted ex vitro if these were pulse-treated with 123 μM each of indole-3-butyric acid and β-naphthoxyacefic acid. The plantlets were transferred to bottles containing sterile ‘soilrite’
(soilless compost and soil conditioner) moistened with half-strength MS macrosalts. Ninety-five percent of the plantlets were
hardened in the bottles within 15 d. The hardened plants were then transferred to black polybags in the nursery. Field transferred
plants are growing normally and have flowered. The protocol developed is reproducible. From a single nodal segment about 1700
hardened plants could be regenerated within 174 d. 相似文献
18.
Protoplasts were isolated from cell suspensions derived from cotyledon and hypocotyl Gentiana kurroo (Royle). Cell walls were digested with an enzyme cocktail containing cellulase, macerozyme, driselase, hemicellulase and
pectolyase in CPW solution. Protoplast viability ranged from 88 to 96%. Three techniques of culture and six media were evaluated
in terms of their efficiency in producing viable cultures and regenerating whole plants. With liquid culture, cell division
occurred in only a low number of the protoplasts isolated, and no plant regeneration was successful. Cell division occurred
within 2 or 3 days in case of agarose solidified media. After 10 days of culture, the number of dividing cells was the highest
with modified MS medium in which NH4NO3 was replaced with 3.0 g l−1 glutamine. The best results were obtained with agarose bead cultures: plating efficiency was 68.7% and 58.1% for protoplasts
isolated from cotyledon and hypocotyl derived suspensions, respectively. The results were achieved with using medium containing
0.5 mg l−1 2,4-D + 1.0 mg l−1 kinetin or 2.0 mg l−1 BAP + 1.0 mg l−1 dicamba + 0.1 mg l−1 NAA + 80 mg l−1 adenine sulfate. Protocalluses transferred on the following composition of plant growth regulators: 0.5 mg l−1 2,4-D + 1.0 mg l−1 kinetin or 1.0 mg l−1 kinetin + 0.5 mg l−1 GA3 + 80.0 mg l−1 adenine sulfate developed in embryogenic cultures. However, the best embryo production occurred with the first one. Later
embryos were transferred to half-strength MS mineral salts to promote plants formation. Flow cytometry studies revealed increased
amounts of DNA in about one third of the regenerants. 相似文献
19.
The genetic relationships ofAechmea mexicana, A. lueddemanniana, A. macvaughii andA. tuitensis were investigated using starch gel electrophoresis. Eight enzyme systems encoded by ten putative gene loci were resolved in seventeen populations.Nei's (1978) genetic distances were obtained from allelic frequencies and used with UPGMA algorithm. Results indicate that some populations belonging to different species display genetic similarities closer to each other than to some conspecific populations. Our results do not support the proposed genusUrsulaea (Read & Baensch 1994), sinceA. tuitensis was closer toA. lueddemanniana andA. mexicana than toA. macvaughii. 相似文献
20.
Yuexia Wang Bridget A. Ruemmele Joel M. Chandlee W. Michael Sullivan Jane E. Knapp Albert P. Kausch 《In vitro cellular & developmental biology. Plant》2002,38(5):460-467
Summary Embryogenic callus induction and plant regeneration systems have long been established for creeping bentgrass (Agrostis palustris Huds.), but little research has been reported on optimal medium for embryogenic callus induction and plant regeneration in
velvet bentgrass (Agrostis canina L.), colonial bentgrass (Agrostis capillaries L.), and annual bluegrass (Poa annua L.). The present study compared 14 callus induction media and eight regeneration media for their efficacies on embryogenic
callus induction and plant regeneration in these four species. The embryogenic callus initiation media contained the Murashige
and Skoog inorganic salts and vitamins supplemented with 2,4-dichlorophenoxyacetic acid or 3,6-dichloro-anisic acid and 6-benzyladenine.
l-Proline or casein hydrolyzate was included in some media to stimulate embryogenic callus formation and plant regeneration.
The frequencies of embryogenic callus formation ranged from 0% to 38% and exhibited medium differences within each of the
four species. Callus induction media, plant regeneration media, and genotypes affected plant regeneration rates, which varied
between 0% and 100%. The embryogenic callus induced on Murashige and Skoog medium supplemented with 500 mgl−1 casein hydrolyzate, 6.63 mg l−1 (30 μM) 3,6-dichloro-anisic acid and 0.5–2.0 mg l−1 (2–9 μM) 6-benzyladenine had much higher regeneration rates than those formed on other callus induction media. Embryogenic callus
of annual bluegrass had higher regeneration rates than those of bentgrass species. MSA2D, a media containing 2 mgl−1 (8 μM) 2,4-dichlorophenoxyacetic acid, 100 mgl−1
myo-inositol, and 150 mgl−1 asparagine, was effective in promoting embryogenic callus formation in creeping bentgrass but not in colonial and velvet
bentgrasses and annual bluegrass. 相似文献