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1.
M. C. J. BOTTINI A. DE BUSTOS A. M. SANSO N. JOUVE L. POGGIO 《Botanical journal of the Linnean Society. Linnean Society of London》2007,153(3):321-328
Sequence analysis of the internal transcribed spacer (ITS) of the 18S(ITS1)-5.8S-26S(ITS2) rDNA region was performed in order to analyse the phylogenetic relationships between 13 Patagonian species of the genus Berberis (Berberidaceae). The divergence values between the pairwise sequence in the studied Patagonian species were in the range 2.9–22.9%. The lengths of the ITS1 and ITS2 sequences were in the range 227–231 bp and 220–224 bp, respectively, and the 5.8S sequence was 159 bp throughout all species . B. microphylla sensu Landrum does not appear to be monophyletic based on current sampling. Indeed, we suggest that B. microphylla should be distinguished from B. buxifolia , B. parodii , and B. heterophylla . ITS sequences, together with data obtained from morphological, biochemical, amplified fragment length polymorphism, and cytological characterizations, support the existence of diploid and polyploid hybrid speciation in the genus. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 321–328. 相似文献
2.
Calceolaria uniflora and C. polyrhiza differ markedly in flower structure, color, and in their pollination mechanisms. Flowers of C. polyrhiza have a hidden glandular oil-secreting appendage that in the genus typically attracts bee pollinators, while in C. uniflora this is replaced by an external, white and fleshy structure that functions as food body and attracts a bird pollinator. Populations with intermediate flower morphology, presumably hybrids, were found in several sites over a large area of southern Patagonia, Argentina. The intermediate forms have so far been found always in contact or close proximity with typical populations of both presumed parent species. The distribution pattern and phenetic intermediacy in several independent flower characters strongly suggest widespread interspecific hybridization in the range of geographic overlap of the two species. The pattern of variation of intermediate forms in some sites is indicative of a hybrid swarm and possible introgression. Of particular interest is the range of intermediate structures and positions of the flower appendage, between oil gland and food tissue, that can be found in hybrid populations. The observed phenomenon raises several questions concerning the biological mechanisms generating it and its evolutionary consequences. Received May 31, 2001 Accepted September 4, 2001 相似文献
3.
报道了中国贵州小檗科小檗属植物一新种,即平坝小檗(Berberis pingbaensis M. T. An)新种与堆花小檗(B. aggregate Schineid.)相近似,但植物较小,果具白粉。 相似文献
4.
采用制作叶脉标本和透明叶标本的方法,对贵州产28种2变种小檗属植物叶脉特征进行比较研究。结果表明:贵州小檗属植物的脉序类型有5种:半达缘羽状脉、花环状半达缘羽状脉、简单弓形羽状脉、花环状弓形羽状脉和混合型。叶脉分支一般有五级:1一级脉构架均为羽状脉,粗度有很粗、粗、中等粗细和纤细四种类型,分支方式包括单轴分支和合轴分支;2粗二级脉构架中有分支达缘或分支均不达缘,与中脉夹角变化各异,内二级脉存在或缺失,细二级脉半达缘、真曲行或简单弓形,间二级脉类型复杂多变但频度种间有差异;3三级脉贯串型、结网型或分支型;4四、五级脉网状或自由分支且常混合在一起。脉间区从发育差到良好,小脉从不分支到不均等分支等各种类型均有,叶缘末级脉缺失、不完整、钉状和环状。大部分种类叶缘具齿,每1cm齿数目和齿内腺点的特性等特征在不同种类间有区别,具有鉴定价值,但齿其它特征复杂多变或种间区别较小,同时齿内脉性状也不稳定。此外,齿的有无会对脉序类型产生影响。小檗属植物叶脉类型存在种间差异,具有重要的分类学价值,叶脉类型的变化和复杂程度显示了该属植物的进化特点;叶齿的有无和齿特征具有分类学和系统学意义。基于叶脉特征的研究结果并结合重要的外部形态学特征编制了贵州小檗属植物的分种检索表。研究结果可为小檗属植物分类寻找新的依据并探讨其系统学意义。 相似文献
5.
The Japanese kelp Undaria pinnatifida was found on 7th September 2005 in Ría Deseado (Santa Cruz, Argentina). This invasive algae was registered from the lower intertidal to the upper levels of the subtidal zone. The sporophytes were fixed to slabs, gravel and rocks of variable sizes and were also present as epibionts of tunicates. The sporophytes total length ranged between 3 and 88 cm, with a mean of 28.75 cm in the intertidal and 38.3 cm in the subtidal. The density and biomass increased from the intertidal to the subtidal. The kelp population showed a higher number of small immature individuals in the intertidal than␣subtidal where the organisms were bigger and with more individual biomass. This first record of U. pinnatifida in Southern Patagonia extends its southern distribution limit in Argentina, showing progressive expansion in the southwestern Atlantic. More surveys must be conducted to understand the evolution of U. pinnatifida invasion and its impact on the native benthic community. 相似文献
6.
Most titanosaur dinosaurs are represented by incomplete skeletal elements lacking articulated pes. An exceptionally preserved specimen from the Late Campanian–Early Maastrichtian strata of Patagonia (Argentina) provides new data on pedal morphology and the evolutionary trends of these huge dinosaurs. This finding is one of the few articulated titanosaur pes known in the world, and shows a phalangeal formula of 2-2-2-2-0. The first three digits possess sickle-shaped claws and the articular facets of ungual phalanges, suggesting mobility in horizontal and vertical planes. A comparative analysis of available record suggests that titanosaurs had a progressive reduction of size and number of pedal phalanges in digits III and IV during the Late Cretaceous. 相似文献
7.
Airborne pollen in San Carlos de Bariloche was sampled from September to March 2001–2004 with a Hirst-type volumetric spore trap placed at a height of 15 m in a city extending from the humid forests, through the mesic forests, to the steppe. The total amount of pollen recorded varied widely from year to year. The pollen index was 4,395 in the sampling period 2001/2002; 9,055 in 2002/2003 and 2,756 in 2003/2004. The main pollen period extended from October to January. In October, pollen concentration was the highest. Sixty-six pollen types were identified. Cupressaceae and Nothofagus were the major contributors. Betula, Prunus, Pinus and Populus, the most abundant ornamental taxa in the city, also contributed to the pollen record. Pollen of Maytenus and Lomatia was representative of the mesic forest, while pollen in the lower layers of the humid forest was present in trace amounts. Cupressaceae, Nothofagus and Betula prevailed during spring (September–December), and Plantago, Rumex and Poaceae during summer (December–March). The association of daily pollen concentration and meteorological variables, temperature (mean, maximum, minimum), dew point, rainfall and wind speed, was significant. Correlations showed to be negative, with the exception of that to wind speed. The total sum of fungi spores increased from 1,771 in 2001/2002; through 8,441 in 2002/2003 to 13,782 in 2003/2004. Relative concentration rose to 29%, 48% and 84% of the total number of pollen and fungal spores recorded during each sampling period. 相似文献
8.
S. Groh A. Zacharias S. F. Kianian G. A. Penner J. Chong H. W. Rines R. L. Phillips 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(6-7):876-884
Amplified fragment length polymorphisms (AFLPs) can be used to quickly develop linkage maps in plant species and are especially
useful for crops with large genomes like oat (Avena sativa L., 2n=6x=42). High reproducibility and consistency are crucial if AFLP linkage maps are employed for comparative mapping.
We mapped AFLP markers in combination with restriction fragment length polymorphism (RFLP) markers in two recombinant inbred
populations of hexaploid oat in two laboratories to test the consistency of AFLP markers in a polyploid crop. Eight primer
combinations produced 102 and 121 scoreable AFLP markers in the respective populations. In a population from the cross Kanota×Ogle,
AFLP markers were placed onto a RFLP reference map consisting of 32 linkage groups. Nineteen linkage groups from another population
from the cross Kanota×Marion were assigned to the reference map using AFLP and RFLP markers homologous to those used in the
Kanota× Ogle cross. Reproducibility of AFLP assays was high in both laboratories and between laboratories. The AFLP markers
were well-distributed across the genome in both populations. Many AFLP markers tended to extend the distance between adjacent
RFLP markers in linkage analysis. Of the 27 polymorphic AFLPs common in both populations, 20 mapped to homologous linkage
groups, 4 were unlinked in at least one population, and 3 mapped to different linkage groups in the two crosses. We believe
that 1 of the 3 markers that mapped to a different linkage group in the two populations mapped to homoeologous linkage groups.
The linkage map of hexaploid oat is not yet complete, and genomic rearrangements such as translocations exist among cultivars
and are likely to account for the remaining two non-syntenous mapping results. AFLPs provide not only a fast and powerful
tool for mapping but could be useful in characterizing genomic structural variations among germplasms in hexaploid oat.
Received: 17 December 1999 / Accepted: 28 July 2000 相似文献
9.
We studied the reproductive behavior of Colletia spinosissima Gmel. at six sites in two regions of Argentina during the 1998–2000 flowering seasons. Flowering takes place in winter. The flowers are homogamous, fragrant, and entomophilous. There was evidence of self-incompatibility and cross-incompatibility between nearby partners. Fruit set of open-pollinated flowers (13.3%) seemed pollen-limited, since low fecundity was consistently associated with small stigmatic pollen loads and with low numbers of successful pollen tubes, and fecundity increased with abundance of efficient pollinators. Reproductive success (percent ovules becoming viable seeds) was 3.6. It is hypothesized that homogamy was established in Colletia because in an impoverished pollination environment – such as the one likely prevailing when this lineage evolved – achieving pollen export and receipt in a single pollinator visit has selective advantages. A large stigma and an extragynoecial compitum would compensate for the homogamy-driven, increased pollen-stigma interference. Received March 8, 2001 Accepted July 19, 2001 相似文献
10.
Grindelia coronensis, a new species from the Meseta del Somuncura, Prov. Río Negro, Argentina, is described and illustrated. It is similar toG. chiloensis (Cornel.) Cabrera but it is readily distinguished by its leaves which are conspicuosly differentiated into a obovate blade and a long petiole. 相似文献
11.
A characteristic xeromorphic foliage occurring in the European Tertiary was originally identified as a Proteaceae according to gross morphology, and compared with Grevillea L. and Lomatia L. (Grevillea kymeana Unger, Lomatites aquensis Saporta). On the basis of venation patterns and phyllotaxy, these elements are now reinterpreted as extinct species of Berberis L. (Berberidaceae): Berberis andreanszkyi spec. nov. occurring in the Upper Oligocene (Eger – Wind brickyard), and the Middle Miocene (Erdbénye) of Hungary, and Berberis kymeana (Unger) comb. nov. (syn. Lomatites aquensis Saporta) known from the Lower Miocene of Greece (Kymi) and the Oligocene of France (Aix-en-Provence, Manosque/Bois d'Asson, Cérestre, Bonieux). The associated vegetation reflects warm-temperate to subtropical subhumid climatic conditions. Extant barberries with similar foliage occur in the Himalayas and China today. Received April 3, 1999 Accepted September 25, 2000 相似文献
12.
Polymorphism, distribution, and segregation of AFLP markers in a doubled haploid rice population 总被引:18,自引:0,他引:18
M. Maheswaran P. K. Subudhi S. Nandi J. C. Xu A. Parco D. C. Yang N. Huang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(1):39-45
We exploited the newly developed amplified fragment length polymorphism (AFLP) technique to study the polymorphism, distribution
and inheritance of AFLP markers with a doubled haploid rice population derived from ‘IR64’/‘Azucena’. Using only 20 pairs
of primer combinations, we detected 945 AFLP bands of which 208 were polymorphic. All 208 AFLP markers were mapped and distributed
over all 12 chromosomes. When these were compared with RFLP markers already mapped in the population, we found the AFLP markers
to be highly polymorphic in rice and to follow Mendelian segregation. As linkage map of rice can be generated rapidly with
AFLP markers they will be very useful for marker-assisted backcrossing.
Received: 11 April 1996 / Accepted: 14 June 1996 相似文献
13.
14.
Julián F. Petrulevičius 《法国昆虫学会纪事》2013,49(1-2):271-275
A new genus of Aeshnidae, Huncoaeshna n. gen., based on Huncoaeshna corrugata n. gen., n. sp., is erected from Laguna del Hunco (Ypresian) in Patagonia Argentina. The specimen presents a special kind of preservation with the middle part of the wing wrinkled. The presence of only two fossil specimens of Aeshnidae in South America is surely due to the lack of paleontomologists and collections of fossil insects in the subcontinent. 相似文献
15.
M. Fregene A. Bernal M. Duque A. Dixon J. Tohme 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(5):678-685
Amplified fragment length polymophism was assessed in 20 land races and nine elite lines of cassava from Africa, resistant
and susceptible to the cassava mosaic disease (CMD). Eleven accessions from a representative core collection from Latin America,
previously studied by AFLPs, were included as a reference. AFLP data from all accessions was analyzed by both the unweighted
pair group mean average (UPGMA) and multiple cluster analysis (MCA) methods of analysis. Genetic differentiation between clusters
and the coefficient of genetic differentiation was also calculated. Results reveal a genetic divergence between African and
Latin American accessions, although some overlap was found between them. African land races resistant to CMD, were also found
to be genetically differentiated from susceptible land races and from resistant elite lines. AFLP analysis identified a considerable
number of duplicates in the African accessions, suggesting a sizeable percentage of redundancy. A unique AFLP fragment, found
in a relatively high frequency in African accessions, but absent in the Latin American accessions, was found to be associated
with branching pattern by QTL mapping in an F1 progeny derived from African and Latin American parents. The likely source
and the utility of the unique AFLP fragment in understanding the processes of genetic divergence in Africa is discussed.
Received: 15 May 1999 / Accepted: 28 July 1999 相似文献
16.
In the intermediate zone of the inflorescence of genera of Aroideae one can find flowers with male and female characteristics. Until now, two types of developmental sequences of atypical bisexual flowers (ABFs) have been recognized: the Philodendron type and the Cercestis type. In the Philodendron type, bisexual flowers generally consist of functional carpels and staminodes inserted on the same whorl. In the Cercestis type, the gynoecium and stamens are inserted on two different whorls. These different ontogenetic patterns represent two different pathways in the evolution of unisexual flowers in this subfamily. A molecular phylogenetic analysis of 33 genera of Araceae, based on the chloroplast trnL intron and trnL–F intergenic spacer sequences was carried out. We use this phylogenetic analysis and those published by French et al. (1995) and Mayo et al. (1997) to examine the distribution of the two types of ABFs in selected genera. Our results suggest that the two developmental patterns of ABFs in Aroideae sensu Mayo et al. (1997) do not correspond to two separate evolutionary lineages but rather are more or less consistent within clades. Although this new molecular phylogeny does not include all aroid genera, it corroborates in general, at the subfamily level, the molecular analysis of French et al. (1995) based on chloroplast DNA restriction site data and the analysis of Mayo et al. (1997) based on morphological and anatomical data. Received March 15, 2001 Accepted October 11, 2001 相似文献
17.
P. Ajmone Marsan C. Gorni A. Chittò R. Redaelli R. van Vijk P. Stam M. Motto 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(2-3):230-243
We exploited the AFLP®1(AFLP® is a registered trademark of Keygene, N.V.) technique to map and characterise quantitative trait loci (QTLs) for grain yield and two grain-related traits of a maize segregating population. Two maize elite inbred lines were crossed to produce 229 F2 individuals which were genotyped with 66 RFLP and 246 AFLP marker loci. By selfing the F2 plants 229 F3 lines were produced and subsequently crossed to two inbred testers (T1 and T2). Each series of testcrosses was evaluated in field trials for grain yield, dry matter concentration, and test weight. The efficiency of generating AFLP markers was substantially higher relative to RFLP markers in the same population, and the speed at which they were generated showed a great potential for application in marker-assisted selection. AFLP markers covered linkage group regions left uncovered by RFLPs; in particular at telomeric regions, previously almost devoided of markers. This increase of genome coverage afforded by the inclusion of the AFLPs revealed new QTL locations for all the traits investigated and allowed us to map telomeric QTLs with higher precision. The present study has also provided an opportunity to compare simple (SIM) and composite interval mapping (CIM) for QTL analysis. Our results indicated that the method of CIM employed in this study has greater power in the detection of QTLs, and provided more precise and accurate estimates of QTL positions and effects than SIM. For all traits and both testers we detected a total of 36 QTLs, of which only two were in common between testers. This suggested that the choice of a tester for identifying QTL alleles for use in improving an inbred is critical and that the expression of QTL alleles identified may be tester-specific. 相似文献
18.
E. S. Mace C. G. Gebhardt R. N. Lester 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(3-4):634-641
The AFLP technique was evaluated as a tool for assessing species relationships within the tribe Datureae and genetic distances
were estimated for 47 accessions of over 12 species. The phenetic trees from various analyses of the AFLP data gave very high
co-phenetic correlation values, and were found to be consistent with previous trees based on the analysis of different data
types, in particular ITS-1 sequences, isozymes and morphology, carried out on the same accessions. These results indicated
that the AFLP technique is both an efficient and effective tool for determining genetic relationships among taxa in the Solanaceae.
A new classification is proposed for the tribe Datureae, which maintains the arborescent species as a separate genus, Brugmansia, and recognises three sections within the genus Datura; Stramonium, Dutra and Ceratocaulis. D. discolor, previously placed in section Dutra, was found to be intermediate between sections Dutra and Stramonium.
Received: 11 January 1999 / Accepted: 1 February 1999 相似文献
19.
Japanese barberry (Berberis thunbergii DC.) is a widespread invasive plant that remains an important landscape shrub represented by ornamental, purple-leaved forms of the botanical variety atropurpurea. These forms differ greatly in appearance from feral plants, bringing into question whether they contribute to invasive populations or whether the invasions represent self-sustaining populations derived from the initial introduction of the species in the late 19th century. In this study we used amplified fragment length polymorphism (AFLP) markers to determine whether genetic contributions from B. t. var. atropurpurea are found within naturalized Japanese barberry populations in southern New England. Bayesian clustering of AFLP genotypes and principal coordinate analysis distinguished B. t. var. atropurpurea genotypes from 85 plants representing five invasive populations. While a single feral plant resembled B. t. var. atropurpurea phenotypically and fell within the same genetic cluster, all other naturalized plants sampled were genetically distinct from the purple-leaved genotypes. Seven plants from two different sites possessed morphology consistent with Berberis vulgaris (common barberry) or B. ×ottawensis (B. thunbergii × B. vulgaris). Genetic analysis placed these plants in two clusters separate from B. thunbergii. Although the Bayesian analysis indicated some introgression of B. t. var. atropurpurea and B. vulgaris, these genotypes have had limited influence on extant feral populations of B. thunbergii. 相似文献
20.
The kelp Undaria pinnatifida(Phaeophyceae) is a seaweed native to northeast Asia, but during the last two decades, it has been accidentally or intentionally introduced in several temperate coasts worldwide. In central Patagonia (Argentina), this species was first detected in late 1992, and it is progressively spreading from the point of introduction. Through a manipulative experiment involving Undaria removal in 2001, we found that its presence is associated with a dramatic decrease in species richness and diversity of native seaweeds in Nuevo Gulf. Future prospects are worrisome, as, in addition to the negative impact from a biodiversity viewpoint, native commercial macroalgae and invertebrates might also be affected. 相似文献