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1.
Ginseng is a well-known medicinal plant that has been used as an anti-aging agent for many years in East Asia. In the genusPanax, only three species,P. ginseng (Oriental ginseng),P. quinquefolius (American ginseng) andP. notoginseng (Chinese ginseng), are currently considered to be important medicinal herbs. Despite the increase in their breeding value, molecular cytogenetic information on the species is not available. To analyze the genomic relationships among thePanax species, FISH (fluorescencein situ hybridization) and GISH (genomicin situ hybridization) techniques were applied. FISH analysis revealed that the 45S and 5S rRNA genes ofP. notoginseng (2n=2x=24) andP. ginseng (2n=4x=48) cluster on a single locus on different chromosomes, whileP. quinquefolius (2n=4x=48),P. japonicus (2n=4x=48), and Korean wild ginseng (2n =4x= 48) had one locus of the 45S rRNA gene and two loci of the 5S rRNA gene, respectively. GISH analysis using genomic DNA as a probe detected strong cross-hybridization of genomes betweenP. ginseng andP. quinquefolius. GISH analysis of other species showed weak or no distinct signals on the chromosomes. Our data revealed thatP. ginseng andP. quinquefolius showed the highest degree of homology, indicating that these species diverged in most recent years.  相似文献   

2.
Panicum amarum andP. amarulum exhibit north-south clinal variation and are virtually indistinguishable in the southern part of their range. Cytological evidence indicates thatP. amarum (2n = 54) is probably an autohexaploid derivative ofP. amarulum (2n = 36). The minor morphological differences, the apparent close genetic relationship, and the close ecological and chemical affinities between these two taxa indicate thatP. amarum andP. amarulum should have varietal rather than specific rank.  相似文献   

3.
Several taxa considered by previous authors as intraspecific ofPotentilla taurica s.l. are considered as separate species. A diploid chromosome number 2n=14 and the characteristic chromosomes of karyotypes of 3 Balkan endemicsP. ni?i?i Adam.,P. emilipopii Nyarády andP. pirotensis (Borb.) Mark. are recorded.P. bornmuelleri Borb.,P. mollicrinis (Borb.) Stankov andP. astracanica Jacq. are widespread in South-eastern Europe. Of this groupP. mollicrinis is a diploid (2n=14),P. bornmuelleri is tetraploid and inP. astracanica a polyploid serie of 2x=14, 4x=28, 5x=35 and 6x=42 has been found. The karyotypes of all species are characterized by submetacentric chromosomes.  相似文献   

4.
Velva E. Rudd 《Brittonia》1981,33(3):435-440
Paramachaerium Ducke, a genus of neotropical trees, has been known hitherto from three species,P. schomburgkii (Guyana and Brazil),P. ormosioides (French Guiana and Brazil), andP. gruberi (Panamá). Two new species are herein described,P. krukovii (western Brazil) andP. schunkei (Peru).  相似文献   

5.
David J. Keil 《Brittonia》1984,36(1):74-80
Four new species ofPectis are described:P. ericifolia from Barbuda,P. luckoviae from west-central Mexico,P. arida from Ecuador and Peru, andP. cajamarcana from Peru. Chromosome counts forP. ericifolia (n=48) andP. luckoviae (n=12) are presented. Relationships of the newly described taxa are discussed.  相似文献   

6.
Chromosome numbers are reported for 19 collections representing 16 AsiaticPotentilla taxa. The first chromosome records are reported forP. desertorum Bunge var.arnavatensis Wolf (2n=28),P. festiva Soják (2n=28),P. griffithii Hook f. subsp.beauvaisii (Cardot) Soják (2n=42),P. micropetala D. Don subsp.byssitecta (Soják) Měsí?ek etSoják (2n=14),P. mollissima Lehm. (2n=28),P. moorcroftii Wall. exLehm. (2n=42),P. multicaulis Bunge (2n=14),P. [x]omissa Soják (2n=35, 56, 70) andP. stanjukoviczii Ovcz. exKoczk. (2n=14). Counts differing from those previously recorded are given forP. algida Soják (2n=56) andP. flagellaris Willd. exSchlecht. (2n=42). Chromosome numbers of the following species were confirmed:P. [x]agrimonioides Bieb. (2n=42),P. chinensis Ser. in DC. (2n=14),P. fragarioides L. (2n=14),P. lineata Trev. (2n=14) andP. sericea L. (2n=28). Taxonomy is briefly discussed. A new combinationP. micropetala D. Don subsp.byssitecta (Soják) Měsí?ek etSoják stat. nov. is proposed.  相似文献   

7.
The new species is the fourth member of the genus. Morphologically, it is most closely allied toP. liebmannii, but there are ample qualitative and quantitative differences between them. The chromosome numbers ofP. liebmannii andP. nelsonii are 2n = 56 whileP. zinnioides is 2n = 84.Philactis fayi is 2n = 28 and is considered to represent the diploid complement that was probably involved in the production of the other species through hybridization and chromosome doubling.  相似文献   

8.
Data derived from a morphological, cytological, flavonoid, and greenhouse study indicate thatParonychia pulvinata (2n = 32) andP. sessiliflora (2n = 64) should be distinguished in specific rank rather than in subspecific rank as recently proposed. Additionally, new evidence is brought to bear onP. depressa var.brevicuspis, which is shown to be synonymous withP. sessiliflora.  相似文献   

9.
The vegetative and floral differences between two frequently confused species are discussed in terms of function.Platanthera psycodes is a widespread species with flowers adapted to visits by short-tongued lepidoptera, especially skippers of the genusPolites; the pollinaria are attached to the base of the proboscis.Platanthera grandiflora is a geographically more limited species with flowers adapted to visits by longer-tongued lepidoptera; the pollinaria are probably attached to compound eyes. The species overlap geographically and phenologically. Chromosome numbers are 2n = 42 in each species. Cultivated plants of each are partially self-incompatible but produce apparently normal embryos when intercrossed. Mechanical, seasonal, ethological, and distributional differences isolate the species.Habenaria andPlatanthera are considered distinct but closely related genera.Platanthera psycodes is based upon a type at L,P. grandiflora on a type at AMES.Platanthera grandiflora andP. psycodes have affinities with three other eastern North American species characterized by tripartite, fringed, or erose labella. Species pairs within this group, based on column structure, includegrandifloraperamoena andpsycodeslacera. The column ofP. leucophaea is morphologically intermediate in form.  相似文献   

10.
《Experimental mycology》1990,14(1):57-69
The purpose of this work was to investigate the inheritance of allozymes and virulence inPhytophthora infestans. For two previously known allozyme systems (glucose phosphate isomerase and peptidase) we discovered new alleles,Gpil (98) andPepl (83 and96). We also determined that a previously uncharacterized enzyme system, mannose phosphate isomerase, had at least two loci and four electromorphs (93, 100, 105, and 111) whose allelic relationships are not yet elucidated. We observed normal segregations in F1 progeny, but there were some unexpected segregations in backcrosses and sibcrosses. One backcross produced predominantly heterozygous progeny for bothGpil andPepl, with the expected classes of homozygotes virtually absent. An excess of heterozygotes forGpil was observed in another backcross, and in sibcrosses there were deficiencies of expected homozygous classes. In F1 progeny, virulence/ avirulence against potato resistance geneR2 segregated in a 1:1 ratio (P = 0.3), while the segregation of virulence/avirulence toR4 departed somewhat from a 1:1 ratio (P = 0.07). These results support the gene-for-gene hypothesis inP. infestans and suggest that virulence againstR2 is controlled at a single locus, while virulence againstR4 may be determined at one or two loci.  相似文献   

11.
Chromosome numbers are reported for 26 collections representing 12 MongolianPotentilla taxa. The first chromosome records are reported forP.[x]agrimonioides Bieb. (2n = 42, 49–50),P. [x]chionea Soják (2n = 64, 74+1B, 84–86, 86),P. [x]stepposa Soják (2n = 62) andP. supina, L. subsp.costata Soják (2n = 42). Tetraploid and pentaploid populations ofP. sericea L. (2n = 28, 34, 35) and hexaploid populations ofP. omithopoda Tausch (2n = 42) were found in Mongolia. Chromosome numbers of the following species were confirmed:P. longifolia Willd. exSchlecht. (2n = 14),P. multifida L. (2n = 28),P. sanguisorba Willd. exSchlecht. (2n = 28),P. sericea L. (2n = 42),P. supina L. subsp.paradoxa (Nutt.) Soják (2n = 28 China) andP. tanacetifolia Willd. exSchlecht. (2n = 28). Taxonomic observations are briefly discussed.  相似文献   

12.
Chromosome numbers are reported for 20 collections of Mongolian plants representing 19 taxa. The first chromosome records are reported forArabidopsis mongolica (2n=16),Caragana pygmaea (2n=16),Isatis costata var.leiocarpa (2n=28),Lophanthus chinensis (2n=18) andStevenia cheiranthoides (2n=32). Counts partly differing from those previously recorded are given forBatrachium trichophyllum subsp.trichophyllum (2n=32+0-2B, 36+6B),Cuscuta chinensis (2n=60),Dracocephalum fragile (2n=72) andErysimum flavum (2n=14). Chromosome numbers of the following taxa were confirmed:Astragalus monophyllus (2n=16),Erodium stephanianum (2n=16),Gastrolychnis apetala (2n=24),Geum aleppicum (2n=42),Linum baicalense (2n=18),Rorippa palustris (2n=32),Rubia cordifolia subsp.pratensis (2n=22),Schizonepeta multifida (2n=12),Tribulus terrestris (2n=36) andVicia cracca (2n=14). Taxonomic remarks onArabidopsis mongolia, Erysimum flavum, Stevenia cheiranthoides andVicia cracca are added. A new combinationArabidopsis mongolica (Botsch.)Měsí?ek & Soják is proposed.  相似文献   

13.
Psathyrella hypertropicalis, a new species, is described from a high mountain (Cofre de Perote) in the State of Veracruz, Mexico above the subtropical zone. This species is intermediate betweenP. velutina of the temperate regions andP. sepulchralis from the subtropical regions of Mexico. A list of the 26 species ofPsathyrella of Mexico is presented, of which 21 are from the tropics and subtropics, three from the temperate regions (P. velutina, P. spadicea, andP. hypertropicalis), and two with a broad distribution (P. candolleana andP. disseminata). Eleven are only known from Mexico.  相似文献   

14.
Preliminary taxonomic and agronomic investigation was made of close relatives of the faba bean (Vicia faba) to aid future plant breeding. Cluster analysis of 2 yr’s morphometric data showed thatV. johannis is clearly separable from other members of theV. narbonensis complex. AlsoV. faba was much more distinct from eitherV. narbonensis orV. johannis than they are from each other. Petal colours at anthesis provided a rapid method of field identification forV. faba, V. narbonensis, andV. johannis. The 2 varieties ofV. johannis can also be distinguished by their petal colours: var. procumbens shows a marked colour change at anthesis and var. johannis does not. The geographical distribution of the plant material studied suggests thatV. johannis is found in Turkey and Europe despite being omitted from the major published floras. BothV. johannis andV. narbonensis possess agronomically useful characters of importance to faba bean breeders, including increased frost tolerance and resistance to bothAphis fabae andBotrytis fabae.  相似文献   

15.
Three species of lepidopterous larvae were collected fromAmaranthus hybridus L. growing in field corn during 1975 and 1976 at Hastings, Florida.Spodoptera exigua (Hubner) was the predominant species in May.Spodoptera eridania (Cramer) was predominant in June andHerpetogramma bipunctalis (F.) in July and August. Nine native species of parasites, representing theBraconidae, Eulophidae, Ichneumonidae andTachinidae, emerged from these larvae.Meteorus autographae Muesebeck emerged from bothS. exigua andS. eridania. TheTachinidae, Winthemia rufopicta (Bigot),Eucelatori rubentis (Coquillett) andLespensia sp., emerged from mixtures ofS. exigua andS. eridania. Apanteles marginiventris (Cresson),Temelucha sp., andChelonus texanus Cresson emerged from bothS. exigua andH. bipunctalis larvae, andEuplectrus platyhypenae Howard andOphion sp. emerged fromS. eridania. All the species of parasites from the lepidopterous larvae that feed onAmaranthus hybridus are also reported as parasites ofS. frugiperda, a serious pest of corn. Therefore these larvae onA. hybridus may be a source of the parasites found attackingS. frugiperda.  相似文献   

16.
Observations on the parasitoids of cotton bollworms in the Punjab were made during 1978 and 1979. The 2 trichogrammatid egg parasitoids, viz.Trichogramma achaeae Nagaraja & Nagarkatti andTrichogrammatoidea sp. nearguamensis Nagaraja (MS) were recovered fromPectinophora gossypiella (Saunders) in addition to 1 braconid egg-larval parasitoidChelonus sp. and 7 larval parasitoids, viz. 4 braconidsApanteles angaleti Muesebeck,Bracon greeni Ashsmead,Camptothlipsis sp. andRogas sp., 1 elasmid,Elasmus johnstoni Ferrière, 1 bethylid,Goniozus sp. and 1 ichneumonid,Scambus lineipes (Morley). FromEarias insulana Boisduval andEarias vittella F., 3 trichogrammatid egg parasitoids,T. achaeae, Trichogramma chilonis Ishii, andT. sp. nearguamensis 2 braconid larval parasitoids,B. greeni andRogas sp. and 1 chalcid pupal parasitoid,Brachymeria nephantidis Gahan, were recovered. One eurytomid hyperparasitoid,Eurytoma braconidis Ferrière was also recovered from the cocoons ofB. greeni. Of these parasitoids,T. achaeae, T. sp. nearguamensis, Camptothlipsis sp. andS. lineipes fromP. gossypiella, T. achaeae andB. nephantidis fromEarias spp. andE. braconidis fromB. greeni are new records.  相似文献   

17.
18.
David J. Keil 《Brittonia》1974,26(1):30-36
Pectis minutiflora,P. papposa var.grandis, andP. purpurea var.sonorae are described as new. A new combination,P. purpurea var.lancifolia also is included. Chromosome counts (n = 12) are reported forP. papposa var.grandis andP. purpurea var.sonorae.  相似文献   

19.
Thirteen species of blue-eyed grasses had been described for the Pacific Northwest prior to this study. Contemporary taxonomic treatments vary; some authors recognize several of the taxa as valid species, others recognize only one highly variable, widely distributed species. Work has been directed to achieve an understanding of the biological integrity of all previously described species within the northwest. Living plants from natural populations were utilized in controlled artificial hybridization experiments, analysis of breeding systems, and cytological investigations. Hybrids of intraand interspecific crosses were examined for pollen fertility, and investigated cytologically for meiotic behavior. Eight genetically compatible groups are indicated from these experiments. Additional information gained from cytological analysis, breeding systems, ecology, distribution, and morphological studies substantiates the recognition of each genetically compatible group at the specific level, including the new species,S. hitchcockii, from southern Oregon. The following taxa are recognized for the Pacific Northwest: tetraploids (n = 16)S. bellum S. Wats.,S. halophilum Greene,S. septentrionale E. P. Bicknell; octoploids (n = 32)S. idahoense E. P. Bicknell (including the vars.segetum,macounii, andoccidentale), andS. hitchcockii D. Henderson; duodecaploids (n = 48)S. idahoense E. P. Bicknell var.idahoense, S. littorale Greene,S. montanum Greene, andS. sarmentosum Suksd. ex Greene.  相似文献   

20.
Natural intersectional hybridization in perityle (Compositae)   总被引:1,自引:0,他引:1  
A small number of supposed F1 hybrids was discovered in an isolated sympatric population ofP. parryi (n = 17) andP. rupestris var.albiflora (n = 17) in the Chisos Mts. of Texas. Although the parental species are morphologically quite distinct, being assigned to separate taxonomic sections ofPerityle, their hybrids displayed relatively high fertility. Origin of the presumed natural hybrids was documented by the production of artificial hybrids betweenP. parryi andP. rupestris var.albiflora. Fertility data based on pollen stainability were accumulated for the available natural hybrids, and for artificial hybrids through F3 and backcross generations. A brief discussion of biosystematic implications is included.  相似文献   

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