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991.
Analysis of the NAC transcription factor gene family in citrus reveals a novel member involved in multiple abiotic stress responses 总被引:1,自引:0,他引:1
992.
Teresa Ribeiro Jo?o Loureiro Concei??o Santos Leonor Morais-Cec��lio 《Tree Genetics & Genomes》2011,7(6):1113-1122
The Fagaceae is one of the most important plant families in European forest ecosystems, and it includes several genera distributed
in the Northern hemisphere. In this work we studied the genome organization and evolution within the family, by karyotyping
and physically mapping rDNA in ten European and Asian species of the genera Fagus, Quercus, and Castanea. All of the species studied had a chromosome number of 2n=2x=24, except for the first report of a single individual of Quercus suber which proved to be triploid (2n=3x=36). The rDNA physical mapping revealed several patterns: the dominant one is present in European and Asian Quercus subgenus Quercus, and in Castanea sativa and Castanea crenata, consisting of two 18S–25S rDNA loci (one subterminal major and one pericentromeric minor) and one 5S rDNA pericentromeric
locus. In Fagus sylvatica and in Quercus sessilifolia, different patterns were observed: four terminal 18S–25S rDNA loci and two 5S rDNA pericentromeric loci in the former, and
five 18S–25S rDNA loci (three terminal and two intercalary) and one 5S rDNA pericentromeric locus in the latter. In Castanea mollissima a distinct rDNA distribution pattern with two intercalary 18S–25S rDNA loci and two 5S rDNA was found. These findings suggest
rDNA loci restructuring during Castanea evolution, and variability of 18S–25S loci between Quercus and Cyclobalanopsis subgenera. 相似文献
993.
Mariem Bouhadida Mar��a ��ngeles Moreno Mar��a Jos�� Gonzalo Jos�� Manuel Alonso Yolanda Gogorcena 《Tree Genetics & Genomes》2011,7(2):257-270
A set of 94 peach cultivars including Spanish native peach and foreign commercial cultivars were analyzed using 15 SSR markers,
selected for their high level of polymorphism. The number of alleles obtained varied from two to 11 with an average of 6.73
giving 185 different genotypes. All the cultivars showed a unique genetic profile, each one using different genotypic combination
of all loci. BPPCT001 was the most informative locus showing also the highest discrimination power. Only six loci allowed
the unambiguous separation of all the Spanish native cultivars studied, and the genotypic combination of only eight loci permitted
the total differentiation of the 94 peach cultivars analyzed. The six selected loci (BPPCT001, BPPCT006, BPPCT008, PS9f8,
UDP98-022, and UDP98-412) seem to be very useful for future Spanish peach identification works, and they will help to establish
a molecular data base for native peach cultivars. UPGMA analysis was performed from the genetic distance matrix, and allowed
the arrangement of all genotypes according to their genetic diversity. The genetic diversity among cultivars, observed in
this work, led to their separation according to their regional origin, their morphological characteristics, and especially
according to their fruit traits. Analysis of molecular variance was performed for seven populations from different regions
of Spain and USA to examine the distribution of genetic variation of the studied accessions, showing that the major variation
occurred within populations in each geographic site. The results reveal the existence of two diversity regions in Spain for
peach germplasm. 相似文献
994.
S-genotyping of old apple cultivars from the Carpathian basin: methodological, breeding and evolutionary aspects 总被引:1,自引:0,他引:1
Julia Hal��sz Attila Heged?s Zsuzsanna Gy?rgy ��va P��llinger Magdolna T��th 《Tree Genetics & Genomes》2011,7(6):1135-1145
Apple exhibits self-incompatibility controlled by the multiallelic S-locus. Twenty-three old apple cultivars were S-genotyped using three different approaches (allele-specific polymerase chain reaction (PCR) + cleaved amplified polymorphic
sequences (CAPS), consensus PCR + sequencing and consensus PCR + CAPS) to compare the robustness and reliability of these
techniques and characterise genotypes from the Carpathian basin that might be useful in resistance breeding. Best results
were obtained using the ASPF3 and ASPR3S consensus primer pair that detected 96% of all alleles carried by the 23 cultivars
tested. Flow cytometry analysis was also needed to control the completeness of the genotypes as was seen in case of a tetraploid
cultivar with only three assigned S-alleles. The genetic disparity between the old Carpathian basin and modern apple cultivars was indicated by differences in
allele frequency data (S
9, S
24 and S
26) as well as single nucleotide polymorphisms in S
1, S
2, S
7
S
24 and S
26 and indels in S
20 and S
26 alleles. An alignment of partial genomic sequences indicated trans-specific and trans-generic evolution of S-ribonuclease alleles in the Maloideae subfamily (S
26 and S
28) and a possibly recent introgression event (S
1) between Malus × domestica and Malus sylvestris. These data suggest that the genome of old cultivars from the Carpathian basin was enriched by several Malus taxa and are free from the consequences of modern breeding. These cultivars may contribute to the widening of the genetic
basis of cultivated apple and prevent genetic erosion in future commercial cultivars. 相似文献
995.
Range-wide chloroplast and mitochondrial DNA imprints reveal multiple lineages and complex biogeographic history for Douglas-fir 总被引:1,自引:0,他引:1
Xiao-Xin Wei Jean Beaulieu Damase P. Khasa Jes��s Vargas-Hern��ndez Javier L��pez-Upton Barry Jaquish Jean Bousquet 《Tree Genetics & Genomes》2011,7(5):1025-1040
The contemporary genetic structure of species offers key imprints of how organisms responded to past geological and climatic
events, which have played a crucial role in shaping the current geographical distribution of north-temperate organisms. In
this study, range-wide patterns of genetic variation were examined in Douglas-fir (Pseudotsuga menziesii), a dominant forest tree species distributed from Mexico to British Columbia in western North America. Two organelle DNA
markers with contrasting modes of inheritance were genotyped for 613 individuals from 44 populations. Two mitotypes and 42
chlorotypes were recovered in this survey. Both genomes showed significant population subdivision, indicative of limited gene
flow through seeds and pollen. Three distinct cpDNA lineages corresponding to the Pacific Coast, the Rocky Mountains, and
Mexico were observed. The split time of the two lineages from the Rockies lineage was dated back to 8.5 million years (Ma).
The most recent common ancestors of Mexican and coastal populations were estimated at 3.2 and 4.8 Ma, respectively. The northern
populations of once glaciated regions were characterized by a high level of genetic diversity, indicating a large zone of
contact between ancestral lineages. A possible northern refugium was also inferred. The Mexican lineage, which appeared established
by southward migration from the Rockies lineage, was characterized by the lowest genetic diversity but highest population
differentiation. These results suggest that the effects of Quaternary climatic oscillations on the population dynamics and
genetic diversity of Douglas-fir varied substantially across the latitudinal section. The results emphasize the pressing need
for the conservation of Mexican Douglas-fir. 相似文献
996.
Antoine Kremer Barbara Vinceti Ricardo Alia Jaroslav Burczyk Stephen Cavers Bernd Degen Reiner Finkeldey Silvia Fluch Dusan G?m?ry Felix Gugerli Hans Peter Koelewijn Jarkko Koskela Fran?ois Lef��vre Michele Morgante Gerhard Mueller-Starck Christophe Plomion Gail Taylor Jozef Turok Outi Savolainen Birgit Ziegenhagen 《Tree Genetics & Genomes》2011,7(4):869-875
This article is a summary report of the international conference "Forest ecosystem genomics and adaptation" organized by the EVOLTREE Network of Excellence in San Lorenzo de El Escorial (Madrid), Spain, from 9 to 11 June 2010. Main achievements and results of the network are presented for the eight thematic sessions and a stakeholder session. The conference has shown that adaptive responses of trees to biotic or abiotic selection pressures can now be investigated at the gene level for traits of adaptive significance. Candidate genes have been catalogued for phenological and drought-related traits in important tree families (Salicaceae, Fagaceaea and Pinaceae), and their variation in natural populations is being explored. Genomics can now be integrated in ecological research to investigate evolutionary response to climate changes in a wide range of species. New avenues of research were also highlighted as the exploration of gene networks involved in adaptive responses and the combination of experimental and modelling approaches to disentangle components of evolutionary changes triggered by climate change. The main focus of the conference was the adaptation of trees to environmental changes. The conference was organized in eight thematic sessions ranging from genomic approaches aiming at identifying genes of adaptive significance to practical issues regarding mitigation options for combating climate change. A dialogue between scientists and end users took place in the form of an ad hoc stakeholder session. A panel of end users from various forest and policy-making institutions expressed their expectations, and the discussions with the scientists addressed the potential applications of research findings to the management of genetic resources in the context of climate changes. The conference was introduced by two keynote speakers Dr. Pierre Mathy from the European Commission, Directorate General of Research, and Dr. Allen Solomon, former National Program Leader for Global Change, US Forest Service. All the thematic sessions were introduced by high-level invited speakers from the respective fields. 相似文献
997.
Rosario Linacero Julia Rueda Estrella Esquivel Alberto Bellido Angel Domingo Ana M. V��zquez 《In vitro cellular & developmental biology. Plant》2011,47(5):618-628
In vitro regenerated plants of rye, Secale cereale L., Ailés and Merced cultivars, were studied to verify if genetic and/or epigenetic changes were promoted by in vitro conditions. Inter-simple sequence repeat (ISSR) fingerprints on HpaII/MspI-digested and uncut DNA were generated. DNA digested with methylation-sensitive isoschizomers revealed epigenetic modifications, while modification of ISSR patterns obtained with undigested DNA indicated genetic changes. With this technique, it was possible to study both genetic and/or epigenetic changes within the same DNA sequences. The frequency of plants with at least one variation was high: 73% and 30% of rye plants showed at least one genetic change, and 50% and 73% carried at least one methylation change, in the Ailés and Merced cultivars, respectively. Further analyses revealed that a considerable number of variable markers showed both types of modifications, indicative of both genetic and epigenetic changes. Moreover, genetic variation was related to the presence of the CCGG target in the analyzed bands. These results indicate the possible existence of a common mechanism connecting both types of variation. 相似文献
998.
M. Elena González-Benito Carmen Martín 《In vitro cellular & developmental biology. Plant》2011,47(1):46-54
Spanish territories contain many of the hot spots of plant biodiversity among European countries. Most of the Spanish territory
is found in the Mediterranean basin and in the Canary Islands, a region of great floral singularity and diversity (Macaronesian
bioregion). Therefore, an important effort must be made to contribute to its conservation. Several strategies can be considered,
but seed conservation under standard conditions is the most resource-efficient method. However, the application of this methodology
is not always possible for recalcitrant seeds or species for which vegetative propagation is necessary or convenient under
some circumstances. Micropropagation is one of the measures suggested for preserving endangered species. During the 1990s,
several in vitro culture protocols for Spanish endemics were established. The main purpose of this strategy was to obtain a considerable number
of individuals to reduce the loss of natural populations. Likewise, diverse slow growth protocols were developed for this
material. However, these efforts usually did not lead to the establishment of in vitro collections. The advantages and disadvantages of the in vitro conservation strategy will be reviewed for some cases. The establishment of the in vitro protocols together with the development of cryopreservation techniques created the ideal conditions to generate cryogenic
collections. In this paper, we review the knowledge and experience accumulated during the last decades in micropropagation,
slow growth, and cryopreservation for Spanish plant wild species. Their application in the development ex situ collections and their contribution toward an integrated system to conserve threatened species will be discussed. 相似文献
999.
1000.
Estrada-Barraza D Dávalos Martínez A Flores-Padilla L Mendoza-De Elias R Sánchez-Vargas LO 《Revista iberoamericana de micología》2011,28(1):36-42
The increase in the incidence of yeast species causing fungemia in susceptible immunocompromised patients in the last two decades and the low sensitivity of conventional blood culture has led to the need to develop alternative approaches for the early detection and identification of causative species. The aim of this study was to compare the usefulness of molecular testing by the polymerase chain reaction (PCR) and conventional methods to identify clinical isolates of different species, using the ID32C ATB system (bioMérieux, France), chromogenic culture Chromagar Candida? (CHROMagar, France) and morphogenesis in corn meal agar. We studied 79 isolates, in which the most prevalent species using the system ID32C and PCR was C. albicans, followed by C. tropicalis, C. glabrata and C .krusei. PCR patterns obtained for the identification of clinical isolates were stable and consistent in the various independent studies and showed good reproducibility, concluding that PCR with species-specific primers that amplify genes ITS1 and ITS2 for rRNA or topoisomerase II primers is a very specific and sensitive method for the identification of C. glabrata, C. krusei, C. albicans, and with less specificity for C. tropicalis. 相似文献