摘要 :
The gametophytic self-incompatibility (GSI) system in Rosaceae has been proposed to be controlled by two genes located in the S-locus: an S-RNase and a recently-described, pollen-expressed, S-haplotype-specific F-box gene (SFB). F...
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The gametophytic self-incompatibility (GSI) system in Rosaceae has been proposed to be controlled by two genes located in the S-locus: an S-RNase and a recently-described, pollen-expressed, S-haplotype-specific F-box gene (SFB). Fragments containing genes homologous to the S-RNase and F-box genes in Prunus species have been described. In apricot (Prunus armeniaca L.), these genes were identified recently. Three identified S-RNase alleles and the F-box allelic variants (SFB1, SFB2 and SFB4) allowed elucidation of the S-locus structure in apricot. In this paper, from the analysis of the S-locus, we carried out the molecular typing of several S-alleles in apricot. A primer pair developed from conserved regions identified in the apricot S-locus was used to amplify the first S-RNase intron. Fragments containing the second intron were obtained using two sets of primers designed from published Prunus avium S-cDNA sequences. These results confirm genotypes established by other methods and establish five self-(in)compatibility groups in apricot..
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摘要 :Broad bean wilt virus 1 (BBWV-1) and BBWV-2 are the two most significant viruses in the genus Fabavirus, causing damage to many economically important agricultural crops worldwide. A quantitative real-time reverse transcription-po...
展开Broad bean wilt virus 1 (BBWV-1) and BBWV-2 are the two most significant viruses in the genus Fabavirus, causing damage to many economically important agricultural crops worldwide. A quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR) procedure using two TaqManReg.MGB probes was developed for sensitive and specific detection and quantitation of BBWV-1 and BBWV-2. Primers and probes were designed from conserved sequence stretches to detect all isolates of each virus. Standard curves using RNA transcripts identical to both TaqManReg.MGB probes enabled absolute quantitation, with a wide dynamic range and high sensitivity (103-1010 RNA molecules). RT-qPCR was assayed with genetically divergent BBWV-1 and BBWV-2 isolates from different plant hosts and countries, and was used to evaluate the temporal accumulation of BBWV-1 RNA in two plant hosts.
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Diospyros kaki Thunb. originated in Eastern Asia, as evidenced of its culture in China as early as several centuries B.C. In the seventh century, persimmon was introduced to Japan and later, in the fourteenth century to Korea. The...
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Diospyros kaki Thunb. originated in Eastern Asia, as evidenced of its culture in China as early as several centuries B.C. In the seventh century, persimmon was introduced to Japan and later, in the fourteenth century to Korea. There is no information about persimmon culture in Europe until the seventeenth century, with the spread over the world occurring in the eighteenth century. The genus Diospyros contains more than 400 species, with levels of ploidy ranging from diploid (2n = 2x = 30) up to nonaploid (2n = 9x = 135). The primary economic crop species is Diospyros kaki Thunb., which is mainly hexaploid (2n = 6x = 90) and includes hundreds of cultivars. Although a relatively recent introduction in Europe, the species has adapted well, and the genetic diversity have been expanded with culture and selection for the past 200 years in the Mediterranean basin. These locally adapted cultivars were evaluated with cultivars from Asian origin in a germplasm collection established at IVIA in Valencia, Spain. In this paper 27 cultivars from the IVIA collection were studied by multivariate analysis, and 37 variables were analyzed using a Principal Components Analysis and cluster analysis following the method UPGMA. Studies on correlations and significance among variables identified the most relevant ones, and thus provided information for a future core collection.
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The search for wild type strains of Erwinia amylovora that do not harbor the plasmid pEA29, has led to the finding of more strains of this pathogen carrying a plasmid of about 70 kb recently described and called pEI70. These strai...
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The search for wild type strains of Erwinia amylovora that do not harbor the plasmid pEA29, has led to the finding of more strains of this pathogen carrying a plasmid of about 70 kb recently described and called pEI70. These strains have been found in collections from countries all over Europe and new screenings are under way with strains from other continents. In our survey, the pEI70 has so far been found in E. amylovora strains from 10 European countries: Spain, Ireland, United Kingdom, Slovenia, France, Italy, Poland, Belgium, Czech Republic and the Netherlands. The numbers of strains carrying this plasmid varied from almost every strain analyzed (e.g., in Belgium) to only a few in other countries. A multiplex PCR protocol has been devised to check for the presence of pEA29 and pEI70 in a single assay. Restriction analyses and hybridizations demonstrated that this large plasmid was similar in all the strains analyzed. Stability after 200-generation serial transfer experiment showed 100% maintenance even in the absence of pEA29. Virulence assays on pear flowers showed no differences between some of these strains and reference E. amylovora strains. The cloning and sequencing of pEI70 is under way to analyze the gene content and perform comparison analyses and identification of putative ORFs, trying to predict its possible role.
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摘要 :
S-locus products (S-RNase and F-box proteins) are essential for the gametophytic self-incompatibility (GSI) specific recognition in Prunus. However, accumulated genetic evidence suggests that other S-locus unlinked factors are als...
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S-locus products (S-RNase and F-box proteins) are essential for the gametophytic self-incompatibility (GSI) specific recognition in Prunus. However, accumulated genetic evidence suggests that other S-locus unlinked factors are also required for GSI. For instance, GSI breakdown was associated with a pollen-part mutation unlinked to the S-locus in the apricot (Prunus armeniaca L.) cv. 'Canino'. Fine-mapping of this mutated modifier gene (M-locus) and the synteny analysis of the M-locus within the Rosaceae are here reported. A segregation distortion loci mapping strategy, based on a selectively genotyped population, was used to map the M-locus. In addition, a bacterial artificial chromosome (BAC) contig was constructed for this region using overlapping oligonucleotides probes, and BAC-end sequences (BES) were blasted against Rosaceae genomes to perform micro-synteny analysis. The M-locus was mapped to the distal part of chr. 3 flanked by two SSR markers within an interval of 1. 8 cM corresponding to ~364 Kb in the peach (Prunus persica L. Batsch) genome. In the integrated genetic-physical map of this region, BES were mapped against the peach scaffold_3 and BACs were anchored to the apricot map. Micro-syntenic blocks were detected in apple (Malus × domestica Borkh.) LG17/9 and strawberry (Fragariavesca L.) FG6 chromosomes. The M-locus fine-scale mapping provides a solid basis for self-compatibility marker-assisted selection and for positional cloning of the underlying gene, a necessary goal to elucidate the pollen rejection mechanism in Prunus. In a wider context, the syntenic regions identified in peach, apple and strawberry might be useful to interpret GSI evolution in Rosaceae.
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The effect of different chilling and gibberellin treatments on growth and development of the peach rootstocks 'Nemaguard' and 'GF305' was studied. A factorial experiment was designed combining cold treatments (0, 5,15 and 30 days ...
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The effect of different chilling and gibberellin treatments on growth and development of the peach rootstocks 'Nemaguard' and 'GF305' was studied. A factorial experiment was designed combining cold treatments (0, 5,15 and 30 days at 4°C temperature)and GA_3 concentrations (0, 100 and 200 mg/L). The variables considered were: percentage of germination, number of internodes, plant height and the ratio plant height/number of internodes. Results showed an overall growth increase as a consequence of chilling and gibberellin addition; however the behaviour of the two assayed rootstocks was slightly different. In general terms, 'Nemaguard' responded well to 5 days cold and chilling treatments did not improve growth in a relevant way, whereas 'GF305' showed a more gradual effect of the chilling and gibberellin treatments on the studied parameters.
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In the present study a commercial solution of chitosan was applied to 'Oronules' mandarins to investigate its effect when applied as a coating at different solids content (0.6, 1.2 and 1.8%). Additionally, one group of mandarins w...
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In the present study a commercial solution of chitosan was applied to 'Oronules' mandarins to investigate its effect when applied as a coating at different solids content (0.6, 1.2 and 1.8%). Additionally, one group of mandarins was coated with a commercial wax, and another group remained uncoated. Mandarins were stored at 5 degrees C for up to 30 d followed by 7 d at 20 degrees C simulating retail conditions. All coatings restricted gas exchange and modified the internal atmosphere of the fruit compared to uncoated mandarins, with a greater effect at higher chitosan concentration. Chitosan-coated mandarins at higher solids content had the highest internal CO2 content and the highest ethanol content. Even though chitosan applied at 0.6% increased the internal level of CO2 of the mandarins, this coating did not increase the amount of ethanol compared to uncoated mandarins. Chitosan application did not decrease mass loss of mandarins during storage, whereas the commercial wax decreased mass loss compared to uncoated control fruit. The internal quality of mandarins was not affected by coating application. All coatings increased the gloss of the fruit. In order to improve the water barrier properties of the chitosan coating, it would be necessary to add hydrophobic components to the formulation.
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Analysis of four genomic regions from 37 geographically diverse isolates of broad bean wilt virus 1 (BBWV-1) showed high genetic diversity in comparison to most plant viruses. Comparison of synonymous and nonsynonymous substitutio...
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Analysis of four genomic regions from 37 geographically diverse isolates of broad bean wilt virus 1 (BBWV-1) showed high genetic diversity in comparison to most plant viruses. Comparison of synonymous and nonsynonymous substitutions of the small coat protein gene (SCP) revealed negative selection for most amino acid positions. Phylogenetic analysis of SCP showed that some BBWV-1 isolates from distant geographical areas were genetically close, suggesting long-distance migration. Analysis of genetic differentiation revealed high gene flow between Spanish and Near Eastern subpopulations, which were separated from North-Central and South-Eastern European subpopulations. Finally, putative recombinant and reassortant genomes were also identified.
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This work is a new approach in the validation of CFD simulations of the distributed greenhouse climate. The validation procedure carried out comprises the characterisation of temperature patterns of a one-span empty greenhouse in ...
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This work is a new approach in the validation of CFD simulations of the distributed greenhouse climate. The validation procedure carried out comprises the characterisation of temperature patterns of a one-span empty greenhouse in summer weather conditions through high spatial resolution temperature measurements. It also comprises a parametric study of 32 simulations of the same simplified case varying the factors: grid, solver precision, wind profile, turbulence model and convergence criterion. And finally, it consists of the comparison between measured data and each one of the simulation results. Our results revealed that main differences among simulations depend on grid quality, structured vs. hybrid mesh, and on turbulence model, standard k- epsilon vs. RNG k- epsilon models. Differences were evaluated in terms of simulation convergence. Climate heterogeneity was determined by standard deviations of distributed temperature. Hence, the difference on temperature standard deviations between measured and simulated data was chosen for comparisons. An analysis of the variance of this parameter against the five factors of the previous parametric study of the simulation confirmed the importance of the grid quality. It also highlighted the consistency of simulation results (represented by standard deviation differences) when a logarithmic wind profile is set as velocity inlet at the beginning of the computational domain with respect to solver precision (3 d and 3 ddp).
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A new symptomatology was observed in celery (Apium graveolens) in Villena, Spain in 2008. Symptomatology included an abnormal amount of shoots per plant and curled stems. These vegetative disorders were associated with 'Candidatus...
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A new symptomatology was observed in celery (Apium graveolens) in Villena, Spain in 2008. Symptomatology included an abnormal amount of shoots per plant and curled stems. These vegetative disorders were associated with 'Candidatus Liberibacter solanacearum' and not with phytoplasmas. Samples from plant sap were immobilized on membranes based on the spot procedure and tested using a newly developed real-time polymerase chain reaction assay to detect 'Ca. L. solanacearum'. Then, a test kit was developed and validated by intralaboratory assays with an accuracy of 100%. Bacterial-like cells with typical morphology of 'Ca. Liberibacter' were observed using electron microscopy in celery plant tissues. A fifth haplotype of 'Ca. L. solanacearum', named E, was identified in celery and in carrot after analyzing partial sequences of 16S and 50S ribosomal RNA genes. From our results, celery (family Apiaceae) can be listed as a new natural host of this emerging bacterium
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