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1.
Genetic variability, population structure and differentiation among 17 populations of 5 species and 2 natural interspecific
hybrids of section Algarobia of genus Prosopis were analyzed from data of 23 isozyme and 28 RAPD loci. Both markers indicated that the studied populations are highly variable.
P. alba populations in average showed lower values of genetic variability estimates from isozyme data, but this trend was not observed
for RAPD markers. The hierarchical analyses of the distribution of genetic variability showed that the highest proportion
of variation occurred within populations, the differentiation among species was intermediate and the lowest component was
observed among populations within species. The consistency between results from both dataset implies that they are not biased
and reflect the actual genetic structure of the populations analyzed. The matrices of Euclidean distances obtained from the
two sets of markers were highly correlated according to Mantel test. In both cases the corresponding phenogram and MDS plot
tended to cluster conspecific populations while hybrid populations were not intermediate between putative parents. Some disagreements
between isozyme and RAPD phenograms were observed mainly in the affinities of hybrid populations. Such inconsistencies might
result from reticular rather than dichotomic evolutionary relationships. The phenetic associations retrieved gave no support
to the division of the section Algarobia into series. 相似文献
2.
G. Landeras M. Alfonso N. M. Pasiecznik P. J. C. Harris L. Ramírez 《Biodiversity and Conservation》2006,15(5):1829-1844
There has been much taxonomic confusion over the identification of Prosopis species, especially where introduced. Prosopis juliflora is the most widespread species in the arid and semi-arid tropics, although it has been confused with other species, particularly
the closely related Prosopis pallida. In this study, RAPDs markers were used for the first time to distinguish between these species. Eighteen primers were used
in amplification reactions, which yielded an average of 120 bands per accession. A dendrogram showing genetic similarities
among accessions was constructed using UPGMA cluster analysis and the Nei and Li similarity coefficient. The genetic similarity
observed between P. juliflora and P. pallida is similar to the value in sympatric Prosopis species in North America, and reconsideration of the series rank in section Algarobia is suggested. Species-specific markers
confirmed that material in Burkina Faso is P. juliflora, but suggested that material collected in Brazil, Cape Verde and Senegal is P. pallida, whereas this has previously been identified as P. juliflora. 相似文献
3.
Brunno Freire Oliveira Gabriel Corrêa Costa Carlos Roberto Fonseca 《Biological invasions》2018,20(1):181-194
Whether or not species track native climatic conditions during invasions (i.e., climate match hypothesis) is fundamental to understand and prevent potential impacts of invasive species. Recent empirical work suggests that climatic mismatches between native and invasive ranges are pervasive. Whether these differences are due to adaptation to new climatic spaces in the invasive range or due to partial filling of the potential climatic space are still subject to debate. Here, we analyze climatic niche dynamics associated with the invasion of the two most common invasive plants in Brazilian semi-arid areas, Prosopis juliflora and Prosopis pallida. These species have been simultaneously introduced in the region, which creates a unique opportunity to compare their niche dynamics during invasion. Given that P. juliflora have a much wider native range size, we expect these species would present different dispersal potentials, which might translate into different unfilling levels. Using an ordination method with kernel smoother and null models, we contrasted climate spaces occupied by each species in both native and invasive ranges. We further used ecological niche models (ENMs) to compare reciprocal predictions of potentially suitable areas. Against our expectation based on differences in native range sizes, climatic niches of P. juliflora and P. pallida overlapped greatly, both in their native and invasive ranges. Our results support niche conservatism during the invasion process. Climatic mismatches among native and invaded ranges were exclusively attributed to unfilling of native climates in the invasive range. Both species showed similar unfilling levels. Likewise, ENMs predicted regions not yet occupied in the invasive range, revealing a potential for further expansion. We discuss colonization time lag and founder effect as potential mechanisms that may have prevented these species to fully occupy their native niches in the invasive range. 相似文献
4.
Transposable elements are important factors driving plant genome evolution. Upon their mobilization, novel insertion polymorphisms
are being created. We investigated differences in copy number and insertion polymorphism of a group of Mariner-like transposable
elements Vulmar and related VulMITE miniature inverted-repeat transposable elements (MITEs) in species representing subfamily Betoideae. Insertion sites of these elements were identified using a modified transposon display protocol, allowing amplification of longer fragments representing
regions flanking insertion sites. Subsequently, a subset of TD fragments was converted into insertion site-based polymorphism
(ISBP) markers. The investigated group of transposable elements was the most abundant in accessions representing the section
Beta, showing intraspecific insertion polymorphisms likely resulting from their recent activity. In contrast, no unique insertions
were observed for species of the genus Beta section Corollinae, while a set of section-specific insertions was observed in the genus Patellifolia, however, only two of them were polymorphic between P. procumbens and P. webbiana. We hypothesize that Vulmar and VulMITE elements were inactivated in the section Corollinae, while they remained active in the section Beta and the genus Patellifolia. The ISBP markers generally confirmed the insertion patterns observed with TD markers, including presence of distinct subsets
of TE insertions specific to Beta and Patellifolia. 相似文献
5.
The Echinacea species are native to the Atlantic drainage area of the United States of America and Canada. They have been introduced as
cultivated medicinal plants in Europe. Echinacea purpurea, E. angustifolia and E. pallida are the species most often used medicinally due to their immune-stimulating properties. This review is focused on morphological
and anatomical characteristics of E. purpurea, E. angustifolia, E. pallida, because various species are often misidentified and specimens are often confused in the medicinal plant market. 相似文献
6.
Hiroyuki Motomura Carl D. Struthers Mark A. McGrouther Andrew L. Stewart 《Ichthyological Research》2011,58(4):315-332
The Scorpaena cardinalis complex, including S. cardinalis, S. jacksoniensis and S. orgila, is defined. The genus Ruboralga (type species: S. jacksoniensis) is regarded as a junior synonym of Scorpaena. Scorpaena jacksoniensis Steindachner 1866, previously treated as a junior synonym of Scorpaena cardinalis Solander and Richardson 1842, is regarded here as a valid species. Scorpaena cookii Günther 1874, previously treated as a valid species, is regarded here as a junior synonym of S. cardinalis. Thus, recent recognition of the two Australasian scorpionfishes, i.e., S. cardinalis and S. cookii, are re-identified in this study as S. jacksoniensis and S. cardinalis, respectively. Scorpaena plebeia Solander 1842 is regarded as a junior synonym of S. cardinalis. Scorpaena jacksoniensis is distributed along the east coast of Australia from southern Queensland to eastern Victoria, whereas S. cardinalis occurs around northern New Zealand, the Kermadec Islands and offshore islands of the Tasman Sea. A neotype is designated
for S. cardinalis. Morphological changes with growth in the two species are described in detail. 相似文献
7.
Summary A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus
and each species are discussed 相似文献
8.
9.
Aihong Zhang Qizhen Chen Li Huang Lin Qiu Jiashu Cao 《Plant Molecular Biology Reporter》2011,29(4):943-951
10.
The current status of Placostromella (Ascomycota, Dothideomycetes inc. sed.) is discussed, and a third species is added to the genus based on Palawaniella castanopsis J.N. Kapoor. Both species occur on living leaves of Castanopsis (Fagaceae) in South and East Asia. Placostromella castanopsis and the type P. macrospora are fully redescribed and illustrated. 相似文献
11.
12.
Isabella Paolucci Muriel Gaudet Véronique Jorge Isacco Beritognolo Serena Terzoli Elena Kuzminsky Rosario Muleo Giuseppe Scarascia Mugnozza Maurizio Sabatti 《Tree Genetics & Genomes》2010,6(6):863-875
White poplar (Populus alba L.) is native to Eurasia and is unexploited for its growth potential and stress-adaptive mechanisms. A better knowledge of
its genome will allow for more effective protection and use of critical genetic resources. The main objective of this study
was the construction of highly informative P. alba genetic maps. Two genotypes were selected from contrasting natural Italian populations and crossed to generate an F1 mapping pedigree. Amplified fragment length polymorphism and simple sequence repeat markers were used to genotype 141 F1 individuals. The pseudo-testcross strategy was applied for linkage analysis. The generated maps showed good overall colinearity
to each other and allowed for a complete alignment with the 19 haploid chromosomes of the Populus genome sequence. The locus that determines sex as a morphological trait was positioned on a non-terminal position of LG XIX
of the female parent map. Comparison among Populus species revealed differences in the location of the sex locus on LG XIX as well as inconsistencies in the heterogametic sex.
The genetic analysis of the sex locus in P. alba provides insights into sex determination in the genus and is useful for the identification of sex-linked markers and the
early assessment of plant gender. Furthermore, these genetic maps will greatly facilitate the study of the genomics of Populus and how it can be exploited in applied breeding programs. 相似文献
13.
Sarawood Sungkaew Atchara Teerawatananon John A. N. Parnell Chris M. A. Stapleton Trevor R. Hodkinson 《Kew Bulletin》2008,63(4):669-673
Summary A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa. 相似文献
14.
Yusuke Hibino Seishi Kimura Kazuo Hoshino Kiyotaka Hatooka John E. McCosker 《Ichthyological Research》2012,59(2):179-188
The myrophine ophichthid fishes (worm eels) Muraenichthys aoki Jordan and Snyder 1901 and Muraenichthys gymnotus Bleeker 1857 are redescribed as valid species of Scolecenchelys based on the types and non-type specimens collected from the Indo-Pacific. Because both species are similar to each other
in having acute snouts, the posterior margin of the eye before the rictus, and their dorsal-fin origins located slightly posterior
to a vertical line through the anus, Scolecenchelys aoki has usually been regarded as a junior synonym of Scolecenchelys gymnota. However, S. aoki is clearly distinguishable from S. gymnota by having a median groove on the ventral side of snout (absent in S. gymnota), uniserial maxillary teeth in smaller specimens (<200 mm TL; vs. biserial), three infraorbital sensory pores at postorbital
area (vs. two), and more numerous vertebrae (56–65 in predorsal vs. 51–57; 53–58 in preanal vs. 47–52). Scolecenchelys aoki is restricted to Japanese waters and regarded as a senior synonym of Muraenichthys borealis Machida and Shiogaki 1990. Scolecenchelys gymnota is widely distributed in the Indo-Pacific, from South Africa and the Red Sea to Samoa, north to Okinawa, Japan. Sphagebranchus huysmani Weber 1913 and Muraenichthys fowleri Schultz 1943 are synonymized under S. gymnota. 相似文献
15.
16.
Summary A new species of Macroptilium sect. Microcochle (Benth.) J. A. Lackey is herein described from the states of Piauí and Bahia, Brazil. Macroptilium cochleatum is characterized by few-flowered inflorescences, calyx teeth longer than the tube, a tightly four-coiled keel, and linear,
patent fruits. The discovery of this unique Macroptilium species, with its distally coiled keel, expands the diagnostic features of the genus. A key to the Brazilian species of sect.
Microcochle is provided. 相似文献
17.
18.
Hisashi Imamura 《Ichthyological Research》2008,55(4):399-406
The type specimens of platycephalid Platycephalus endrachtensis Quoy and Gaimard 1825 are regarded as being conspecific with Platycephalus arenarius Ramsay and Ogilby 1886, so the latter becomes a junior synonym. This species is characterized as having a caudal fin with four or more longitudinal
dark bands and lacking a yellow blotch. It is also found that Platycephalus westraliae (Whitley 1938), which had been considered to be a junior synonym of Platycephalus bassensis Cuvier 1829, is a valid species. Specimens that recently had been mistakenly identified as “P. endrachtensis,” having the caudal fin with three or four longitudinal dark bands and a yellow blotch on the upper lobe, should be referred
to P. westraliae. 相似文献
19.
JS Gonçalves LM Ferracin ML Carneiro Vieira BT Iamanaka MH Taniwaki MH Pelegrinelli Fungaro 《World journal of microbiology & biotechnology》2012,28(4):1817-1825
Brazil nuts are an important export market in its main producing countries, including Brazil, Bolivia, and Peru. Approximately
30,000 tons of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs with subsequent production of aflatoxins. In our study, Aspergillus section Flavi were isolated from Brazil nuts (Bertholletia excelsa), and identified by morphological and molecular means. We obtained 241 isolates from nut samples, 41% positive for aflatoxin
production. Eighty-one isolates were selected for molecular investigation. Pairwise genetic distances among isolates and phylogenetic
relationships were assessed. The following Aspergillus species were identified: A. flavus, A. caelatus, A. nomius, A. tamarii,
A. bombycis, and A. arachidicola. Additionally, molecular profiles indicated a high level of nucleotide variation within β-tubulin and calmodulin gene sequences
associated with high genetic divergence from RAPD data. Among the 81 isolates analyzed by molecular means, three of them were
phylogenetically distinct from all other isolates representing the six species of section Flavi. A putative novel species was identified based on molecular profiles. 相似文献
20.
Genome predictions based on selected genes would be a very welcome approach for taxonomic studies. We analyzed three genes,
recN, flaA, and ftsY, for determining if these genes are useful tools for systematic analyses in the genus Anoxybacillus. The genes encoding a DNA repair and genetic recombination protein (recN), the flagellin protein (flaA), and GTPase signal docking protein (ftsY) were sequenced for ten Anoxybacillus species. The sequence comparisons revealed that recN sequence similarities range between 61% and 99% in the genus Anoxybacillus. Comparisons to other bacterial recN genes indicated that levels of similarity did not differ from the levels within genus Anoxybacillus. These data showed that recN is not a useful marker for the genus Anoxybacillus. A 550–600-bp region of the flagellin gene was amplified for all Anoxybacillus strains except for Anoxybacillus contaminans. The sequence similarity of flaA gene varies between 61% and 76%. Comparisons to other bacterial flagellin genes obtained from GenBank (Bacillus, Pectinatus, Proteus, and Vibrio) indicated that the levels of similarity were lower (3–42%). Based on these data, we concluded that the variability in this
single gene makes it a particularly useful marker. Another housekeeping gene ftsY suggested to reflect the G+C (mol/mol) content of whole genome was analyzed for Anoxybacillus strains. A mean difference of 1.4% was observed between the G+C content of the gene ftsY and the G+C content of the whole genome. These results showed that the gene ftsY can be used to represent whole G+C content of the Anoxybacillus species. 相似文献