首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Three different types of epicuticular wax columns were foundinBrassicaspecies with a chromosome number (n)=9: long columns(LC), short columns (SC) and netted columns (NC). LC were foundinB. incanaandB. rupestris.SC were found inB. villosa, B. macrocarpa,B. cretica, B. hilarionisand also inB. montana. B. insulariscolumnswere intermediate. NC waxes were found inB. oleraceaand itsclose alliesB. alboglabraandB. bourgeaui.Samples ofB. rapa (n=10)andB.nigra (n=8)examined did not show any wax columns but their amphidiploidswithB. oleracea (B. napusandB. carinata,respectively) seemedto inherit the NC type of wax present inB. oleracea.Copyright1999 Annals of Botany Company Brassica, waxes, wax columns, leaf surface.  相似文献   

2.
Genetic diversity in 36 populations of wild taxa of theBrassicaoleraceaL. group (2n=18) and two cultivated forms was studiedusing isozyme variation at 11 loci for five enzyme systems (IDH,6-PGD, PGM, PGI, MDH). Mean values for the percentage of polymorphicloci and expected heterozygosity were 54% and 0.224, respectively.Statistically significant differences among allele frequencieswere found with the 6-PGD isozyme system. Intrapopulationalgenetic diversity was 67% while interpopulational genetic diversitywas only 33%. The dendrogram obtained, using genetic distancesamong taxa, showed three different groups. With the exceptionofB. incana,they agree to the already accepted relationshipsamong the 14 taxa studied: the West Mediterranean group, withB.oleracea, B. alboglabra, B. bourgeauiandB. incana; another groupof species growing in the central Mediterranean area, whichincludesB. villosa, B. villosasubsp.drepanensis, B. rupestris,B. macrocarpa(the four taxa together withB. incanaare consideredtheB. rupestrisgroup) andB. montana; and finally the Aegeangroup, which includes the three subspecies ofB. cretica.Clearlyseparated wereB. insularisandB. hilarionis, showing the maximumgenetic distance. Separate dendrograms were also obtained forB.oleracea, B. montana, B. creticaandB. rupestrisgroup, and geneticdiversity parameters were estimated. Genetic distances amongB.oleraceapopulations are in the same range as populations oftheB. creticasubspecies. Highest genetic distances were foundamong populations of theB. rupestrisgroup.Copyright 1998 Annalsof Botany Company. Brassica oleraceaL., wild relatives, genetic diversity, genetic resources, isozymes.  相似文献   

3.
Mei J  Li Q  Qian L  Fu Y  Li J  Frauen M  Qian W 《Heredity》2011,106(6):955-961
Although there are a number of different allopolyploids in the plant kingdom, the exact ancestral parents of some allopolyploids have not been well characterized. We propose a strategy in which virtual allopolyploid lines derived from different types of parental species are used to investigate the progenitors of an allopolyploid. The genotypes of the parental lines and the natural allopolyploid were established using a set of DNA molecular markers. The genotypes of the virtual lines were then derived from those of the parental lines, and compared extensively with that of the natural allopolyploid. We applied this strategy to investigate the progenitors of the C subgenome of Brassica napus (rapeseed, AACC). A total of 39 accessions from 10 wild and 7 cultivated types of the B. oleracea cytodeme (CC), and 4 accessions of B. rapa (AA) were used to construct 156 virtual rapeseed lines. Genetic structure was compared among natural rapeseed, virtual rapeseed lines, and their parental lines by principal component analysis and analysis of ancestry. Our data showed that the C subgenome of natural rapeseed was related closely to the genome of cultivated B. oleracea and its related wild types, such as B. incana, B. bourgeaui, B. montana, B. oleracea ssp. oleracea and B. cretica. This finding indicated that these types or their progeny might be ancestral donors of the C subgenome of rapeseed. The successful application of the strategy of virtual allopolyploidy in rapeseed demonstrates that it can possibly be used to identify the progenitors of an allopolyploid species.  相似文献   

4.
A population genetic analysis of chloroplast and nuclear DNA was performed covering nine wild populations of Brassica oleracea. Three members of the n = 9 group, all close to B. oleracea, Brassica alboglabra Bailey, Brassica bourgeaui (Webb) O. Kuntze and Brassica montana Pourret, were also studied to better understand their relationship with B. oleracea. Chloroplast DNA was analysed using the PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) method. The ISSR-PCR (inter-simple sequence repeat - polymerase chain reaction) technique was adopted to study nuclear DNA. Twelve primer pairs of chloroplast DNA showed very good amplification. The amplified product of each primer pair, digested by three restriction enzymes, revealed no variation of cpDNA among the taxa studied. This indicates they may have the same chloroplast genotype. Seven selected ISSR primers have detected genetic variation, both within and among the populations/taxa surveyed. The information obtained on the intra- and inter-populational genetic diversity of wild populations of B. oleracea neatly defined the individual plants. It could provide important guidelines for backing management and conservation strategies in this species. The study confirms a close relationship between B. alboglabra, B. bourgeaui and B. montana, which is parallel to their morphological similitude.  相似文献   

5.
This paper presents the evaluation of genetic diversity in 29populations of wild taxa of theBrassica oleraceaL. group (2n=18)and two cultivars, using RAPDs as molecular markers. In a previouspaper (Lázaro and Aguinagalde,Annals of Botany82: 000–000,1998), 11 isozymes were used for the same purpose. Results obtainedwith the two molecular markers (isozymes and RAPDs) are compared.DNA from ten individuals per population was analysed using sixdifferent primers; the 151 detected bands were polymorphic,11 were common to all species, six to all taxa, only one toevery population; and no bands were shared by every individual.The dendrogram obtained using genetic distances clustersB. oleraceapopulationswithB. bourgeaui, B. alboglabra, B. montanaandB. incana. B.insularis, B. macrocarpa, B. villosaandB. rupestrispopulationsform another cluster. Populations ofB. creticaandB. hilarionisformthe third cluster. Genetic diversity inB. oleraceapopulations,theB. rupestriscomplex andB. creticasubspecies was estimatedusing the AMOVA programme; the latter was the most diverse.Copyright1998 Annals of Botany Company. Brassica oleraceaL., wild relatives, genetic diversity, genetic resources, RAPD markers, AMOVA.  相似文献   

6.
Sixteen seed accessions of four Brassica species (B. cretica,B. incana, B. montana and B. oleracea) were examined following5-22 years' storage in the germplasm bank. Germinability andisozyme of seeds stored under long-term (-10 °C and 3% moisturecontent) and short-term (5% °C and 8% moisture content)storage conditions were compared. Long-term storage producedno deterioration and the ability to germinate was satisfactorilymaintained over 8-22 years. Short-term storage conditions maintainedgermination ability up to 10-12 years in all accessions of B.cretica and B. montana. However, seed multiplication might beessential every 10 years for some accessions of B. oleraceastored in this way. In the 8 to 9-year-old accessions of B.cretica, B. incana and B. montana, no significant differenceswere detected between conservation systems for germinabilityand frequency of seeds showing isozyme activity for seven enzymesystems (ACO, IDH, MDH, ME, PGI, PGM and 6-PGD). However, significantdifferences were found for the ADH enzyme system. Moreover,in the 5-22-year-old B. oleracea accessions, significant differenceswere found between storage conditions with respect to isozymeactivity for all enzyme systems studied.Copyright 1995, 1999Academic Press Brassica cretica, Brassica incana, Brassica montana, Brassica oleracea, accessions, isozymes, germination, seed storage  相似文献   

7.
The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol) obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 ) were tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecium (ATCC23212), Pseudomonas aeruginosa (ATCC27853), Escherichia coli (ATCC11229), Salmonella choleraesuis (ATCC10708), Klebsiella pneumoniae (ATCC13883), and Candida albicans (a human isolate). Better antimicrobial activity was observed with D. communis and D. montana var. montana ethyl acetate extracts. Phytochemical analyses from D. communis, D. montana var. montana and D. brevifolia yielded 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin); long chain aliphatic hydrocarbons were isolated from D. communis and from D. villosa var. villosa, a mixture of long chain aliphatic alcohols and carboxylic acids, was isolated from D. communis and 3b-O-acetylaleuritolic acid from D. villosa var. villosa.  相似文献   

8.
AGUINAGALDE, I., GOMEZ-CAMPO, C. & SANCHEZ-YELAMO, M. D., 1992. A chemosystematic survey on wild relatives of Brassica oleracea L. A study on 12 taxa of n = 9, wild Brassica species (including wild B. oleracea) has led to the detection of 21 different flavonol-glycosides. Differential patterns have been obtained for each taxon. Seed proteins and five isoenzyme systems have been analysed by polyacrylamide gel electrophoresis. The presence of many bands common to ail species was the rule for seed proteins, but differences in polypeptide contents were observed. There were also clear qualitative differences in isoenzyme patterns. Interspecific differences were examined by including those phytochemical characters in a numerical analysis. While the maximum morphological variability occurs in Sicily, phytochemical diversity seems to be maximum further east, in the B. cretica group.  相似文献   

9.
Unionicola poundsi and U. lasallei are recognized as closely related, morphologically distinct species of water mites living in symbiotic association with the mussels Villosa villosa and Uniomerus declivus, respectively. However, results of a transplant experiment suggested that the morphological characters used to separate these species are plastic and are influenced by the host species in which these mites metamorphose. These results indicate that U. poundsi and U. lasallei are variants of the same species. To test the validity of these contrasting notions, the genetic structure of mite populations from Uniomerus declivus and V. villosa was compared. An examination of allozyme variation at 9 enzyme loci revealed a high degree of genetic differentiation between these host-associated populations, with mites from U. declivus and V. villosa being fixed for different alleles at 3 loci and exhibiting significant allele heterogeneity at 71% of their polymorphic loci. Coefficients of genetic similarity and genetic distance for mites from U. declivus and V. villosa were 0.36 and 0.95, respectively. The results of this study suggest that mite populations from U. declivus and V. villosa are genetically distinct and complement morphological data recognizing them as valid species.  相似文献   

10.
Feeding behaviour of the specialist Brassicae aphid, Brevicoryne brassicae (L) (cabbage aphid) and the generalist, Myzus persicae, (Sulzer) (peach potato aphid) was monitored electronically on the susceptible cauliflower, Brassica oleracea var. botrytis cv Newton Seale, and a range of 17 Brassica species, B. carinata, B. juncea, B. nigra, B. macrocarpa, and B. villosa var. drepanensis and cultivated brassica varieties, B. oleracea, B. campestris and B. napus. Aphids, monitored for 10 h on the underside of leaves, performed recognisable feeding behaviour on all brassica species. The main differences in feeding behaviour, between M. persicae and B. brassicae, on the susceptible cauliflower Newton Seale, were fewer probes, shorter times to initially reach the phloem but longer times to establish sustained phloem ingestion and the longer times spent, by M. persicae, in xylem ingestion.Feeding behaviour on the range of brassica species tested indicated that generalist and specialist aphids are influenced differently by the host plant. A longer time spent in xylem ingestion was again the major difference in the feeding behaviour of the two aphids. In addition, rejection of passive phloem ingestion, by M. persicae, was not related so closely to increased time spent in non probing activities, as for B. brassicae. This observation indicates that M. persicae does not generally accept or reject brassica species due to the presence of phagostimulants, such as glucosinolates at the leaf surface or along the stylet pathway, unless the concentration is very high. Differences in feeding strategies employed by generalist and specialist aphids on the same plants are discussed.  相似文献   

11.
The hybrid origin of the western Mediterranean orchid Dactylorhiza insularis was demonstrated by genetic markers. Allozyme data showed that throughout its range D. insularis has an allotriploid constitution and reproduces apomictically. The parental species of D. insularis were identified as D. romana andD. sambucina; they contributed 2 alleles and 1 allele, respectively, at the allozyme loci studied. The maternal species of D. insularis was D. romana , as inferred from cpDNA ( trn L(UAA) intron). High genetic similarities were found when comparing present populations of D. romana and D. sambucina with their respective genomes 'frozen' in D. insularis. Dactylorhiza insularis showed fixed (or nearly fixed) heterozygosity at 11 out of the 19 loci studied, and poor genetic variation: eight multilocus genotypes were detected at allozyme level. No multilocus genotype differs from the most similar one by more than one allele substitution. All D. insularis individuals showed the same cpDNA haplotype (I) , regardless of their geographic origin and multilocus genotype. The I haplotype is similar, but not identical to that found in D. romana (R). No recurrent formation of D. insularis was observed in hybrid zones between D. romana and D. sambucina , where diploid sexual hybrids (F1; Fn, backcrosses) were detected. Available data agree with a single origin for D. insularis , which possibly occurred in the present postglacial, when D. romana and D. sambucina , expanding from their glacial refugia, came into contact. The genetic homogeneity found between D. romana and D. markusii , both from their locus classicus , indicates that the latter is a junior synonym of D. romana; on the other hand, D. romana and D. sambucina are well differentiated species ( DNei = 0.59).  相似文献   

12.
Self-incompatibility (SI) systems are widespread mechanisms that prevent self-fertilization in angiosperms. They are generally encoded by one genome region containing several multiallelic genes, usually called the S-locus. They involve a recognition step between the pollen and the pistil component and pollen is rejected when it shares alleles with the pistil. The direct consequence is that rare alleles are favored, such that the S-alleles are subject to negative frequency-dependent selection. Several theoretical articles have predicted the specific patterns of polymorphism, compared to neutral loci, expected for such genes under balancing selection. For instance, many more alleles should be maintained and populations should be less differentiated than for neutral loci. However, empirical tests of these predictions in natural populations have remained scarce. Here, we compare the genetic structure at the S-locus and microsatellite markers for five natural populations of the rare species Brassica insularis. As in other Brassica species, B. insularis has a sporophytic SI system for which molecular markers are available. Our results match well the theoretical predictions and constitute the first general comparison of S-allele and neutral polymorphism.  相似文献   

13.
Anthyllis montana is a submediterranean, herbaceous plant of the southern and central European mountains. The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA were sequenced from multiple accessions of the species and several closely related taxa. In addition, amplified fragment length polymorphism (AFLP) was analysed from 71 individuals of A. montana collected in 20 localities, mainly in the Pyrenees, Alps, Italian Peninsula and Balkans. Our ITS phylogeny showed a sequential branching pattern in A. montana, implying a western Mediterranean origin followed by an eastward migration. ITS clock calibrations suggest that speciation of A. montana took place at the Pliocene-Pleistocene boundary, while intraspecific divergence dates to Late Quaternary times (i.e. 0.7 million years ago). The AFLP analyses revealed a major genetic (west/east) subdivision within A. montana, probably caused by the massive glaciation of the Alps during this latter time period. The present-day absence of A. montana from vast parts of the Alps, which appear ecologically suitable for the species, together with the finding of evenly distributed AFLP variability within each of the two western and eastern lineages identified, is taken as evidence for a largely static Late Quaternary history without large-scale migration. High levels of AFLP variation observed among populations, together with weak or absent patterns of isolation by distance, seem to be in accord with long-term population insularization and distributional stasis. However, recent small-scale migration and a narrow hybrid zone between western and eastern lineages need to be postulated to explain the intermediate genetic composition of individuals from the Maritime Alps, a well-known suture-zone for other plant and animal species.  相似文献   

14.
Edh K  Widén B  Ceplitis A 《Molecular ecology》2007,16(23):4972-4983
Nuclear and chloroplast microsatellite markers were used to study population structure and gene flow among seven Cretan populations of the Aegean endemic plant species Brassica cretica (Brassicaceae). Both nuclear and chloroplast markers revealed exceptionally high levels of population differentiation (overall F(ST)=0.628 and 1.000, respectively) and relatively little within-population diversity (overall H(S)=0.211 and 0.000, respectively). Maximum-likelihood estimates of directional migration rates were low among all pairs of populations (average Nm=0.286). There was no evidence that differences in flower colour between populations had any influence on historical levels of gene flow. In addition, a haplotype network showed that all five chloroplast haplotypes found in the sample were closely related. Together, these results suggest that current patterns of diversification in B. cretica are mainly a result of genetic drift during the last half million years. The main conclusions from the present study are consistent with the prevailing hypothesis that plant diversification in the Aegean region is driven by random rather than adaptive differentiation among isolated populations.  相似文献   

15.
The results of the essential oil composition confirm that there are differences between populations within the same subspecies (Satureja montana ssp. montana, between the subspecies (Satureja montana ssp. montana and Satureja montana ssp. pisidica) and the species (Satureja montana and S. kitabelii). The essential oil composition of S. montana ssp. montana is more related to the Satureja montana ssp. pisidica than S. kitaibelii which separates as a whole species.  相似文献   

16.
An uncharacterized lectin from Vicia villosa seeds has been reported to bind specifically to mouse cytotoxic T lymphocytes (Kimura, A., Wigzell, H., Holmquist, G., Ersson, B., and Carlsson, P., (1979) J. Exp. Med. 149, 473-484). We have found that V. villosa seeds contain at least three lectins which we have purified by affinity chromatography on a column of immobilized porcine blood group substances eluted with varying concentrations of N-acetylgalactosamine and by anion exchange chromatography. The three lectins are composed of two different subunits with Mr = 35,900 (subunit B) and 33,600 (subunit A), estimated from their mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Sedimentation equilibrium analysis suggests that the purified lectins are tetramers. They have been designated B4, A4, and A2B2 to indicate their apparent subunit compositions. The purified B4 and A4 lectins contain 6.7-9.8% carbohydrate by weight; in addition, both are rich in the acidic and hydroxylic amino acids and lack cysteine and methionine. The A4 lectin agglutinates A erythrocytes specifically and binds to A1 erythrocytes (273,000 sites/cell) with an association constant of 1.8 X 10(7) M-1. Although a blood group A agglutinating activity was recognized in the original preparation of V. villosa lectins, lectins with this activity were obtained in relatively small amounts from seed extracts. The predominant lectin in V. villosa seeds, B4, does not agglutinate A, B, or O erythrocytes.  相似文献   

17.
Simple, reliable methods for identification of species are required for management of many species and lines in a plant gene bank. Species-specific probes were designed from published sequences of the ITS1 region in rDNA of 16 species in Brassica and its related genera, and used as probes for dot-blot hybridization with plant genomic DNA. All the probes detected species-specific signals at dot-blots of genomic DNAs of the 16 species in Brassica, Diplotaxis, Eruca, and Raphanus. Signals of the Brassica digenomic species in the U’s triangle, i.e., B. napus, B. juncea, and B. carinata, were detected by the probes of their parental monogenomic species, i.e., B. rapa, B. nigra, and B. oleracea. The probe for B. oleracea showed signals of B. balearica, B. cretica, B. incana, B. insularis, and B. macrocarpa, which have the C genome as B. oleracea. Eruca vesicaria DNA was detected by the probe for E. sativa, which has been classified as a subspecies of E. vescaria. DNA of leaf tissue extracted by an alkaline solution and seed DNA prepared by the NaI method can be used directly for dot-blotting. Misidentification of species was revealed in 20 accessions in the Tohoku University Brassica Seed Bank. These results indicate dot-blot hybridization to be a simple and efficient technique for identification of plant species in a gene bank.  相似文献   

18.
Rao GY  Andersson S  Widén B 《Heredity》2002,88(3):197-202
In the present investigation of Brassica cretica, a wild relative of the cultivated cabbage, B. oleracea, we performed an extensive crossing experiment, involving self-pollinations, random outcrosses within populations and hybridizations between populations or species, to evaluate the relationship between crossing distance and developmental stability, estimated as the absolute difference between the right and left lobe of the cotyledons. The frequency distribution of the right-minus-left scores had a narrower peak than expected for normally-distributed data, but there was no directional asymmetry or antisymmetry. Despite evidence for inbreeding depression in seedling biomass and cotyledon size, the type of cross had negligible influence on cotyledon asymmetry. Separate analyses of between-population hybrids revealed differences among progenies from different pairs of populations and a tendency for the F1 hybrid means to decrease with the geographic distance separating the parent populations, but only for the two size variables. Based on these and other observations, we propose that the degree of cotyledon asymmetry is unrelated to genome-wide characteristics, such as the level of heterozygosity and genomic co-adaptation, and that cotyledon asymmetry is unrelated to the level of genetic stress experienced by each individual. Hence, there is no reason to consider measures of asymmetry as more sensitive indicators of genetic health than conventional fitness variables.  相似文献   

19.
W Tu  Y Li  Y Zhang  L Zhang  H Liu  C Liu  C Yang 《Journal of plant physiology》2012,169(15):1463-1470
Berteroa incana (B. incana), a spring ephemeral species of Brassicaceae, possesses very high photosynthetic capacities at high irradiances. Exploring the mechanism of the high light use efficiency of B. incana under strong light conditions may help to explore mechanisms of plants' survival strategies. Therefore, the photosynthetic characteristics of B. incana grown under three different light intensities (field conditions (field): 200-1500μmolphotonsm(-2)s(-1); greenhouse high light (HL) conditons: 600μmolphotonsm(-2)s(-1); and greenhouse low light (LL) conditions: 100μmolphotonsm(-2)s(-1)) were investigated and compared with those of the model plant Arabidopsis thaliana (A. thaliana). Our results revealed that B. incana behaved differently in adjusting its photosynthetic activities under both HL and LL conditions compared with what A. thaliana did under the same conditions, suggesting that the potential of photosynthetic capacity of B. incana might be enhanced under strong light conditions. Under LL conditions, B. incana reached its maximum photosynthetic activity at a much higher light intensity than A. thaliana did, although their maximum photochemical efficiency of photosystem II (PSII) (F(v)/F(m)) was almost the same. When grown under HL conditions, B. incana showed much higher photosynthetic capacity than A. thaliana. A detailed analysis of the OJIP transient kinetics of B. incana under HL and LL conditions revealed that HL-grown B. incana possessed not only a high ability in regulating photosystem stoichiometry that ensured high linear electron transport, but also an enhanced availability of oxidized plastoquinone (PQ) pool which reduced non-photochemical quenching (NPQ), especially its slow components qT and qI, and increased the photochemical efficiency, which in turn, increased the electron transport. We suggest that the high ability in regulating photosystem stoichiometry and the high level of the availability of oxidized PQ pool in B. incana under strong light conditions play important roles in its ability to retain higher photosynthetic capacity under extreme environmental conditions.  相似文献   

20.
Calocedrus rupestris Aver., H.T. Nguyen & L.K. Phan was described in 2008 based on some morphological characters that were not sufficiently significant to discriminate it as a species distinct from C. macrolepis Kurz. We applied a new approach to resolve these conflicting views by using sequence data from DNA (ITS) to elucidate phylogenetic relationships between the two species. Analyses of a partial ITS1 sequence in 5 individuals of 2 subpopulations of C. macrolepis and 18 individuals of 8 subpopulations of C. rupestris collected in Vietnam were done. Molecular characterization of the two species showed its low divergence with the lack of autapomorphic characters. In addition, the ITS1 partial sequences of some C. rupestris individuals were identical with C. macrolepis. Due to the less distinctive morphology between C. rupestris and C. macrolepis, the divergence between them does not exceed the interspecific levels, and therefore, C. rupestris could not be regarded as an independent species in relation to C. macrolepis but only as one of its varieties, C. macrolepis var. rupestris (Aver., H.T. Nguyen & L.K. Phan) L.K. Phan, Long K. Phan & Aver.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号