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1.
2.
The somatic chromosome numbers of the eleven Australian seagrass species belonging to five genera in the Family Cymodoceaceae were determined. The chromosome numbers in Amphibolis and Thalassodendron are reported for the first time. Cymodocea and Halodule species have the following chromosome numbers: Cymodocea angustata Ostenf., 2n = 14, 28; C. rotundata Ehrenb. & Hempr. ex Asch., 2n = 14; C. serrulata (R. Br.) Asch. & Magnus, 2n = 14, 28; Halodule pinifolia (Miki) den Hartog, 2n = 32; H. uninervis (Forsk.) Asch., 2n = 32; H. tridentata (Steinh.) Endl. ex Unger, 2n = 14. Halodule has the highest chromosome numbers among the seagrasses and they are the largest in sizes with a distinct bimodal type in the family. Syringodium isoetifolium (Asch.) Dandy has 2n = 20. Both endemic Amphibolis antarctica (Labill.) Sonder ex Asch. and A. griffithii (J. Black) den Hartog have 2n = ca. 36 and have the smallest chromosomes in the family appearing as small dots. Thalassodendron pachyrhizum den Hartog has 2n = 28. Chromosome numbers appear to be identical or closely related among different species in the same genus but they vary in the five genera in the Cymodoceaceae suggesting that these five genera may have evolved independently in the past.  相似文献   

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4.
Scilla talosii Tzanoudakis etKypriotakis from the islet of Dia is described as a new species. It is an autumn-flowering taxon related toScilla autumnalis L. andS. obtusifolia Poiret but distinct morphologically and cytologically from both these taxa.S. talosii is polyploid with 2n=ca. 150 chromosomes.  相似文献   

5.
Nuclear genome size, as measured by flow cytometry with propidium iodide, was used to investigate the relationships within the genus Eucomis L’Hér. (Hyacinthaceae). Most species of Eucomis have the same basic chromosome number, x = 15. However, the somatic DNA 2C-value (2C) is shown to range from 21 to 31 pg for the diploids. The largest genome contains roughly 1010 more base pairs than the smallest. Genome sizes are evaluated here in combination with available morphological and geographical data. Therefore, the taxonomy proposed here is not based on genome size alone. The genus Eucomis, as here determined, has 12 species. These can be divided into two groups: mainly dwarf diploid species and large-sized, tetraploid species. A small diploid plant, Eucomis (autumnalis subsp.) amaryllidifolia, is restored to species status, as a diploid subspecies seems incongruent with an allotetraploid Eucomis autumnalis. Moreover, as a diploid it is separated reproductively from the allotetraploid E. autumnalis. A new diploid species that has the lowest C value, E. grimshawii, is described here. On the basis of DNA content and other morphological characters, possible parents are suggested for all tetraploid species. Nuclear DNA content as measured by using flow cytometry may conveniently be used to produce systematic data. It is applicable even in dormant bulbs or sterile plants for the monitoring of the trade in bulbous species.  相似文献   

6.
The role of vermicompost leachate (VCL) on growth, photosynthetic pigments, phytochemical content and the bioactivities of three bulbous (Eucomis autumnalis, Tulbaghia ludwigiana and Tulbaghia violacea) plants with medicinal and horticultural potential under nutrient-stressed conditions was evaluated. After 15 weeks, the nutrient-stressed plants were harvested and growth parameters were recorded. Spectrophotometric methods were used to quantify the photosynthetic and phytochemical contents. Harvested plant materials were extracted with 50 % methanol and subjected to antioxidant, acetylcholinesterase inhibitory (AChEI) and antifungal bioassays to elucidate the effect of the applied VCL under nutrient stress. While VCL did not significantly enhance growth of the three species, it significantly increased photosynthetic pigment content in 50 % Hoagland’s-treated Eucomis autumnalis and in phosphorus-deficient Tulbaghia ludwigiana. Among the quantified phytochemicals, the most promising finding was the significant increase in condensed tannin and iridoid contents in VCL-supplemented-nutrient-stressed Tulbaghia violacea. Better antioxidant (Eucomis autumnalis) and AChEI (Eucomis autumnalis, Tulbaghia violacea) activities were detected when VCL was applied under nutrient stress. The current findings indicate that the application of VCL holds potential in cultivation of plants under nutrient-stressed conditions.  相似文献   

7.
The effects of plant growth regulators (PGRs) and organic elicitors (OEs) on in vitro propagation of Eucomis autumnalis was established. Three-year-old ex vitro grown plants from organogenesis of E. autumnalis and somatic embryogenesis (previously reported protocol) of Drimia robusta were investigated for antibacterial activity. In vitro propagation from leaf explants of E. autumnalis was established using different PGRs and OE treatments for mass propagation, biomass production and bioactivity analysis to supplement the use of wild plant material. Prolific shoots (16.0?±?0.94 shoots per explant) were obtained with MS (Murashige and Skoog in Physiol Plant 15:473–497, 1962) medium containing 100 mg l?1 haemoglobin (HB), 10 µM benzyladenine (BA) and 2 µM naphthaleneacetic acid (NAA). The shoots were rooted effectively with a combination of 2.5 µM indole-3-acetic acid and 5.0 µM indole-3-butyric acid. The plantlets were successfully acclimatized in a vermiculite-soil mixture (1:1 v/v) in the greenhouse. Three-year-old ex vitro-grown E. autumnalis and D. robusta plants derived via organogenesis and somatic embryogenesis respectively exhibited antibacterial activity and varied with PGR and OE treatments, plant parts and bacteria. The leaves of E. autumnalis ex vitro-derived from a combination of HB, BA and NAA followed by the individual treatments of BA and HB gave the best antibacterial activities (<?1 mg ml?1: minimum inhibitory concentration from 0.098 to 0.78 mg ml?1) against all tested pathogenic bacteria (Bacillus subtilis, Enterococcus faecalis, Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa). The bulbs of D. robusta ex vitro-derived from solid culture with 10 µM picloram, 1 µM thidiazuron and 20 µM glutamine exhibited good antibacterial activity against E. faecalis, M. luteus and S. aureus when compared with other treatments and mother plants. The ex vitro-grown E. autumnalis and D. robusta biomass produced with PGRs along with OE treatments confirmed a good potent bioresource and can be used as antibacterial agents. The in vitro plant regeneration of E. autumnalis and D. robusta protocols and ex vitro plants could be used for conservation strategies, bioactivity and traditional medicinal use.  相似文献   

8.
Eucomis species is a valuable plant with both medicinal and horticultural potential. The current study evaluated the role of plant growth regulator (PGR) on growth, phytochemicals, and antioxidant activity in Eucomis autumnalis subspecies autumnalis. Five cytokinins including topolins and benzyladenine (BA) at 2 µM in combination with varying (0–15 µM) concentrations of naphthalene acetic acid (NAA) were tested. In vitro regenerants were acclimatized in the greenhouse for 4 months. Highest number of shoots (9 shoots/explant) was observed with 15 µM NAA alone or when combined with BA. Acclimatized plants derived from the 15 µM NAA treatment had the highest number of roots, largest leaf area and biggest bulbs. While applied PGRs increased the iridoids and condensed tannins in the in vitro regenerants, total phenolics and flavonoids were higher in the PGR-free treatment. Among the in vitro regenerants, 5 µM NAA and 2 µM BA treatments produced the best antioxidant activity in the DPPH (55 %) and beta-carotene (88 %) test systems, respectively. A remarkable carry-over effect of the PGR was conspicuous in the phytochemical levels and antioxidant activity of the 4-month-old plants. In addition to the optimized micropropagation protocols, the current findings present a promising potential for manipulating the type and concentration of applied PGRs to improve phytochemical production and hence medicinal value in E. autumnalis subspecies autumnalis.  相似文献   

9.
Crossability relationships between six species of the Mediterranean, North American and Asian firs was tested using Abies alba and A. nordmanniana as female parents and A. alba, A. numidica, A. procera, A. grandis, and A. holophylla as pollen parents. An overwhelming majority of the crosses attempted was found to be compatible. In particular, it is true of the A. alba cross with A. numidica and those of A. nordmanniana with A. alba, A. numidica, A. procera, and A. holophylla. The crossing A. nordmanniana × A. grandis was the only exception producing empty seeds. Cytological study revealed the gametophytic incompatibility to be responsible for reproductive isolation of these species. At seedling level, all the interspecific crosses of A. nordmanniana surpassed in height growth self-pollinated control. The cross A. alba × A. numidica was comparable in this respect with control variants from open and self-pollination. Except for height growth, some characteristics of needle stomata are provided for individual crosses. The crosses A. nordmanniana with A. procera and A. holophylla represent unique interspecific combinations whose existence has not been reported yet. Based on needle stomata characteristics, the potential for increased resistance and drought tolerance of the hybrids with A. numidica involved as parental species is discussed.  相似文献   

10.
The effect of a seaweed-derived biostimulant (Kelpak® at 1, 2.5 and 5 % dilution; v/v) on the growth, endogenous cytokinin (CK) and phytochemical content in Eucomis autumnalis (Mill.) Chitt. under hydroponic conditions was evaluated. After 4 months, the stimulatory effect of Kelpak® treatments was more noticeable in the underground organs than in the aerial organs. Total endogenous CK was also higher in plants treated with Kelpak® (c.a. 1000–1200 pmol g?1 DW) compared to control plants (860 pmol g?1 DW). Isoprenoid CKs (which mainly accumulated in the aerial organs) were more dominant than aromatic-type CKs across all the treatments. A total of 11 bioactive chemicals (8 phenolic acids and 3 flavonoids) and eucomic acid known for their diverse biological activities were quantified in the samples. The most abundant compound was p-coumaric acid (6.5 µg g?1 DW) and it was approximately sevenfold higher in 2.5 % Kelpak®-treated plants than in the control. It was also noteworthy that syringic acid only occurred in the underground organs of 5 % Kelpak®-treated plants. Eucomic acid which is a major bioactive compound in E. autumnalis was significantly enhanced in Kelpak® treatments, and the leaves accounted for more than 70 % of the overall content. Thus, Kelpak® elicited a significant influence on the growth, endogenous CK and phytochemical content in E. autumnalis. These findings provide additional evidence of the enormous potential of Kelpak® as a useful biostimulant with practical applications in various agricultural endeavours.  相似文献   

11.
Chromosome data are important for elucidating intergeneric relationships and delimiting infrafamilial tribes in plants. This paper reports karyological data for 12 Seriphidium (Bess.) Poljak. species from China, of these, five count as new reports and the others have been reported elsewhere. We also report the tetraploid level in S. schrenkianum for the first time. The karyotype formulae and types for the five new reports are: S. schrenkianum (Ledeb.) Poljak. 2n = 4x = 36 = 22m + 12sm + 2st, S. sublessingianum (Kell.) Poljak. 2n = 2x = 18 = 14m + 4sm and S. transiliense (Poljak.) Poljak. 2n = 2x = 18 = 4M + 6m + 2m(SAT) + 4sm + 2sm(SAT), belong to 2A type; S. cinum (Berg. ex Poljak.) Poljak. 2n = 2x = 18 = 8m + 10sm and S. sawanense Y. R. Ling et C. J. Humphries 2n = 2x = 18 = 10m + 2m(SAT) + 6sm, belong to 2B type. Furthermore, we estimated karyotype asymmetry in the 12 species by using an intrachromosomal asymmetry index and an interchromosomal asymmetry index. The data increase information about the karyosystematics of Seriphidium.  相似文献   

12.
Merwilla plumbea (Lindl.) Speta is a popular and highly sought after South African medicinal plant with diverse therapeutic values. Using Ultra performance liquid chromatography (UPLC), the effect of five cytokinins (CKs) [either isoprenoid = N 6-isopentenyladenine (iP) or aromatic = benzyladenine, meta-topolin (mT), meta-topolin riboside (mTR), and 6-(3-methoxybenzylamino)-9-tetrahydropyran-2-ylpurine] MemTTHP on growth and level of endogenous CKs during micropropagation and acclimatization stages was evaluated. Aromatic CK (mT/mTR) elicited the highest shoot proliferation (7–8 shoots per explant) during in vitro culture. Following acclimatization, iP-treated and the control plants were healthier with longer leaves, roots and higher fresh weight when compared to aromatic CKs. A total of 37 (22 isoprenoid and 15 aromatic) CK variants were quantified in both in vitro and acclimatized plants. Based on their metabolic function, these were grouped into five types including free bases, ribosides, ribotides, O- and 9-glucosides. In addition to enhancing our understanding of the hormone physiology in M. plumbea, the current findings are discussed in line with the effect of the exogenously applied CK on the observed differences in growth before and after the important stage of acclimatization. The observed dynamics in endogenous CK provide an avenue to manipulate in vitro growth and development of investigated species.  相似文献   

13.
Karyotypic characters, mitotic metaphase chromosomes, monoploid idiograms and karyograms of Minuartia anatolica (Boiss.) Woronow var. phrygia (Bornm.) McNeill, Minuartia anatolica (Boiss.) Woronow var. scleranthoides (Boiss. & Noe) McNeill, Minuartia corymbulosa (Boiss. & Balansa) McNeill var. gypsophilloides McNeill and Minuartia aksoyi M.Koç & Hamzao?lu were investigated for the first time. Analysis of somatic metaphases showed that the chromosome numbers and the formulas of these taxa were 2n = 24 = 14m + 6sm + 4st for Minuartia anatolica var. phrygia, 2n = 14 = 6m + 8sm for Minuartia anatolica var. scleranthoides, 2n = 14 = 6m + 4sm + 4st for Minuartia corymbulosa var. gypsophilloides and 2n = 30 = 14m + 10sm + 6st for Minuartia aksoyi. No satellites were observed in the karyotypes of these taxa. Karyotype asymmetry was estimated by many different methods, namely the Stebbins classification, the karyotype asymmetry index (As K %), the total form percent (TF %), the Rec and Syi indices, the intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2), the dispersion index (DI), the degree of asymmetry of karyotype (A index) and the asymmetry index (AI).  相似文献   

14.
The genus Charybdis Speta (previously Urginea maritima agg.) was investigated karyologically and genetically throughout its geographic range in the Mediterranean. The different ploidy levels show a strong geographic pattern. Diploid populations are mainly found along the northern coast of Africa with C. pancration extending northwards from Tunisia to southern Italy. Tetraploid populations are most densely distributed in the eastern Mediterranean but are also found in North Africa, on the Balearic and Canary Islands. Hexaploid populations are restricted to the Iberian Peninsula and adjacent Morocco and Algeria. Chloroplast microsatellite data suggest that determination of ploidy levels alone is insufficient to adequately describe the existing populations. Especially the tetraploid and hexaploid populations exhibit additional genetic differentiation and geographic structuring. AFLP data indicate that tetraploid populations from southern Italy are of hybrid origin. Phylogenetic analysis further revealed that the genera Urginea Steinh. and Charybdis are not directly related to each other but have strong ties to genera from southern Africa. A possible colonization scenario of the Mediterranean via NW Africa and Iberia is discussed.  相似文献   

15.
Although most of the hybrid embryos aborted at an early developmental stage, a 2n = 27 true intergeneric hybrid between Dendranthema indica (L.) Des Moul (2n = 36) as ♀ and Crossostephium chinense (L.) Makino (2n = 18) as ♂ was produced following pollination and ovule rescue. The morphology of the resulting adult putative hybrid and the two parents differed significantly from one another in seven of the nine traits measured, the exceptions being leaf width and leaf length, for which the putative hybrid was indistinguishable from the maternal plant. Genomic in situ hybridization experiments were able to successfully distinguish the genomic origin of both mitotic and meiotic metaphase chromosomes in the hybrid. In addition, the 18 D. indica chromosomes were paired as bivalents at meiotic metaphase in the hybrid.  相似文献   

16.
O. Bakkendorf 《BioControl》1971,16(4):363-366
Oligosita tominici n. sp. is described, bred fromErythroneura eburnea (Cicadellidae) and a key to theminima-group is given.Anagrus atomus (L.) is recorded fromErythroneura eburnea, too, andAnaphes autumnalis Foerster is bred from an egg ofTipula autumnalis Loew; it is the first record of an egg-parasite ofTipulidae.  相似文献   

17.
Coscinopleurid cheilostome bryozoans are widespread in Latest Cretaceous sediments throughout the whole Boreal Chalk Sea. Despite having many polymorphs that can readily be distinguished, intraspecific plasticity is high and polymorph morphology shows only little variation over time. This significantly hampers taxon differentiation in coscinopleurids. In this study, we revise type material of three coscinopleurid species, Acoscinopleura foliacea (Voigt, 1930), A. fallax Voigt, 1956 and A. rugica Voigt, 1956, from the Maastrichtian of northern Germany using combined scanning electron microscopy and X-ray microtomography. The three species are morphologically very similar and were distinguished by the original author only in the shape and position of peripheral caverns inside their cryptocyst and in the position of vibracular polymorphs. X-ray microtomography allowed study of the internal morphology of the species and provided additional parameters that can be used for species differentiation. Septula, arch-like and channel-like cavities and microcavities could be identified inside the calcified walls. While the original identity of the type material of A. foliacea and A. rugica remains unchanged, the type material of A. fallax is shown to belong to three different species: A. fallax, A. occulta sp. nov. and A. dualis sp. nov. Additionally, hitherto-unstudied material from the late Campanian and Maastrichtian of northern Germany and Belarus is described as A. crassa sp. nov. and A. albaruthenica sp. nov.  相似文献   

18.
Two new N-glycosidase type-1 ribosome-inactivating proteins (RIPs), denoted petroglaucin 1 and petrograndin, respectively, were isolated from the plantsPetrocoptis glaucifolia (Lag.) Boiss sp.viscosa (Rothm.) Laínz andPetrocoptis grandiflora Rothm. These new RIPs do not share H2N-terminal amino-acid sequence homology with petroglaucin (now denoted as petroglaucin 2), the only other type-1 RIP to be isolated fromP. glaucifolia (Arias et al. (1992) Planta186, 532–540). Petroglaucin 1 shares amino-acid sequence homology with RIPs from Cucurbitaceae while petroglaucin 2 and petrograndin do so with saporins and dianthin 30 (Caryophyllaceae). The new RIPs strongly inhibited protein synthesis at subnanomolar concentrations in rabbit reticulocyte lysates and other eukaryotic cell-free systems, but they were inactive on bacterial ribosomes.  相似文献   

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20.
Kenaf (Hibiscus cannabinus L.) and roselle (H. sabdariffa L.) are valuable fibre crop species with diverse end use. Phylogenetic relationship of 73 accessions of kenaf, roselle and their wild relatives from 15 countries was assessed using 44 inter-simple sequence repeat (ISSR) and jute (Corchorus olitorius L.) specific simple sequence repeats (SSR) markers. A total of 113 alleles were identified of which 61.95 % were polymorphic. Jute specific SSR markers exhibited high polymorphism and resolving power in kenaf, although ISSR markers exhibited higher resolving power than SSR markers. Number of polymorphic alleles varied from 1 to 5 for ISSR and 1 to 6 for SSR markers. Cultivated species exhibited higher allele polymorphism (57 %) than the wild species (35 %), but the improved cultivars exhibited lower genetic diversity compared to germplasm accessions. Accessions with common genetic lineage and geographical distribution clustered together. Indian kenaf varieties were distinct from cultivars bred in other countries and shared more genetic homology with African accessions. High genetic diversity was observed in the Indian (J = 0.35–0.74) and exotic kenaf germplasm collections (J = 0.38–0.79), suggesting kenaf might have been introduced in India from Africa through Central Asia during early domestication. Genetic similarity-based cluster analysis was in close accordance with taxonomic classification of Hibiscus.  相似文献   

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