共查询到20条相似文献,搜索用时 531 毫秒
1.
T. Cadalen C. Boeuf S. Bernard M. Bernard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(3-4):367-377
An intervarietal molecular marker map covering most of the nuclear genome was developed in Triticum aestivum. One hundred and six androgenetic-derived doubled haploid lines obtained from the F1 between monosomics of ‘Chinese Spring’ and ‘Courtot’ were analysed for genetic mapping. The map covered 18 of the 21 chromosomes
with an identical distribution of markers in the A and B genome, and only small segments of the D genome. Distorted markers
were mapped using Bailey’s 2-point method and revealed skewed regions on 1A, 1DS, 2A, 2B, 4AS and 6B. Comparison with a wide
cross [‘Opata’×Synthetic hexaploid (T. tauschii/‘Altar 84’)] showed colinearity for markers on homologous chromosomes, but revealed a large proportion (25%) of markers mapped
on non-homoeologous chromosomes, i. e. heterologous markers. The origin of the material and distortion segregation are discussed
with particular emphasis on investigations of D-genome markers.
Received: 2 May 1996 / Accepted: 2 August 1996 相似文献
2.
The gene for phospholipase D (PLD) of Streptomyces sp. YU100 was cloned from λ phage library and hetero-logously expressed in Escherichia coli. Using an amplified gene fragment based on the consensus sequences of streptomycetes PLDs, λ phage library of Streptomyces sp. YU100 chromosomal DNA was screened. The sequencing result of BamHI-digested 3.8 kb fragment in a positive phage clone revealed the presence of an open reading frame of a full sequence of
PLD gene encoding a 540-amino acid protein including 33-amino acid signal peptide. The deduced amino acid sequence showed
a high homology with other Streptomyces PLDs, having the highly conserved ‘HKD’ motifs. The PLD gene excluding signal peptide sequence was amplified and subcloned
into a pET-32b(+) expression vector in E. coli BL21(DE3). The recombinant PLD was purified by nickel affinity chromatography and compared the enzyme activity with wild-type
PLD. The results imply that the recombinant PLD produced by E. coli had the nearly same enzyme activity as PLD from Streptomyces sp. YU100. 相似文献
3.
Mandy M Cox Sherryll L Layton Tieshan Jiang Kim Cole Billy M Hargis Luc R Berghman Walter G Bottje Young Min Kwon 《BMC biotechnology》2007,7(1):59
Background
A variety of techniques have been described which introduce scarless, site-specific chromosomal mutations. These techniques can be applied to make point mutations or gene deletions as well as insert heterologous DNA into bacterial vectors for vaccine development. Most methods use a multi-step approach that requires cloning and/or designing repeat sequences to facilitate homologous recombination. We have modified previously published techniques to develop a simple, efficient PCR-based method for scarless insertion of DNA into Salmonella enteritidis chromosome. 相似文献4.
Salmonella typhi (strain Ty2—4446) cultivatedin vitro within the macrophage of mice immunised twice specifically with a high dose of killed vaccine, multiplied less intensively
than in the cells of non-immunised control animals during 24 hours cultivation. In addition, a certain suppression of growth
ofSalmonella enteritidis andSalmonella suis var. Kunzendorf was observed in the macrophages of mice immunised withSalmonella typhi vaccine. Double immunisation of mice with high doses of killed vaccine fromSalmonella enteritidis andSalmonella suis led to the mice macrophages being able to suppress multiplication of both homologous microbes andSalmonella typhi. The formation of such cross resistance in mice immunised with salmonella vaccines excludes the possible participation of
O, H, and Vi antibodies in this phenomenon. 相似文献
5.
Brachmann A König J Julius C Feldbrügge M 《Molecular genetics and genomics : MGG》2004,272(2):216-226
We describe a versatile strategy for generating gene replacement mutants in the phytopathogenic fungus Ustilago maydis. The system includes the choice of 32 different insertion cassettes for genetic engineering purposes, such as gene disruption and more sophisticated insertions of reporter genes, heterologous promoters or combinations of the two. PCR-amplified flanking sequences needed for homologous recombination are ligated to the respective insertion cassettes via Sfi I sites. As proof of principle we generated two replacement mutants in which the endogenous promoter of the pheromone gene mfa1 drives expression of the Green Fluorescent Protein gene (gfp). Simultaneously, expression of the mfa1 ORF is controlled either by the carbon source-regulated crg1 promoter or the nitrogen source-regulated nar1 promoter. In both cases gfp expression was pheromone-inducible and pheromone expression was only detected when the heterologous promoters were active.Communicated by G. JürgensThe first two authors contributed equally to this work 相似文献
6.
Louis-Philippe Bergeron-Sandoval Aurélie Girard François Ouellet Denis Archambault Fathey Sarhan 《Molecular biotechnology》2011,47(2):157-168
A Nicotiana benthamiana transient expression system was used to express single antigen and dimeric combinations of the human rotavirus (HRV) VP7
and a truncated VP4 (VP4Δ) proteins fused with Salmonella typhimurium’s flagellin fljB subunit. Immunoblot analyses using rabbit antibodies generated against these proteins demonstrated that
the constructs were successfully expressed with yields ranging from 0.85 to 31.97 μg of recombinant protein per gram of fresh
leaf tissue. Expressing the single and dimeric antigens has no effect on plant growth and development except for VP7 and VP4Δ::VP7,
which show mild necrotic lesions. Immunization of mice with proteins from leaves transformed with constructs bearing the fljB
moiety elicited an fljB-specific humoral response. The Nicotiana benthamiana transient system is efficient to express multiple combinations of pathogen proteins and demonstrates the potential of generating
a Salmonella typhimurium subunit vaccine in plants. 相似文献
7.
Prashant G. Golegaonkar Haydar Karaoglu Robert F. Park 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(7):1281-1288
An incompletely dominant gene conferring resistance to Puccinia hordei, Rph14, identified previously in an accession of Hordeum vulgare, confers resistance to all known pathotypes of P. hordei in Australia. Knowledge of the chromosomal location of Rph14 and the identification of DNA markers closely linked to it will facilitate combining it with other important leaf rust resistance
genes to achieve long lasting resistance. The inheritance of Rph14 was confirmed using 146 and 106 F3 lines derived from the crosses ‘Baudin’/‘PI 584760’ (Rph14) and ‘Ricardo’/‘PI 584760’ (Rph14), respectively. Bulk segregant analysis on DNA from the parental genotypes and resistant and susceptible DNA bulks using
DArT markers located Rph14 to the short arm of chromosome 2H. DArT marker bPb-1664 was identified as having the closest genetic association with Rph14. PCR based marker analysis identified a single SSR marker, Bmag692, linked closely to Rph14 at a map distance of 2.1 and 3.8 cm in the ‘Baudin’/‘PI 584760’and ‘Ricardo’/‘PI 584760’ populations, respectively. 相似文献
8.
An expression vector constructed from genes of Pichia pastoris was applied for heterologous gene expression in Saccharomyces cerevisiae. Recombinant hepatitis B surface antigen was synthesized by cloning hepatitis B virus ‘S’ gene under the control of glyceraldehyde-3-phosphate
dehydrogenase (GAP) promoter of Pichia pastoris in Saccharomyces cerevisiae. Hepatitis B surface antigen was constitutively expressed, was stable and exhibited ∼20–22 nm particle formation. Stability
and absence of toxicity to the host with the expression vector indicates the expression system can be applied for large-scale
production. 相似文献
9.
Hilde Nybom Artur Mikiciński Larisa Garkava-Gustavsson Jasna Sehic Mariusz Lewandowski Piotr Sobiczewski 《Trees - Structure and Function》2012,26(1):199-213
Fire blight (Erwinia amylovora) causes serious damage to pome fruit orchards, and identification of germplasm with heritable disease resistance is therefore
crucial. Two dominant SCAR (sequence characterised amplified region) marker alleles (AE10-375 and GE-8019), flanking a previously
identified QTL (quantitative trait locus) for resistance to fire blight on ‘Fiesta’ linkage group 7 in apple cultivars related
to ‘Cox’s Orange Pippin’, were screened on 205 apple cultivars. Both marker alleles were present in 22% of the cultivars,
indicating presence of the QTL allele for tolerance, and both were lacking in 25%, indicating homozygosity for absence of
the QTL tolerance allele. However, 33% had only the marker allele AE10-375, while 20% had only GE-8019, suggesting that some
cultivars with the dominant alleles for both of the flanking markers can carry these on separate chromosomes and may lack
the QTL allele for tolerance. In 2009 and 2010, terminal shoots of greenhouse-grown grafted trees of 21 cultivars (only 20
in 2010) were inoculated with Erwinia amylovora. ‘Idared’ (susceptible) and ‘Enterprise’ (tolerant) were included as controls. Disease severity for each cultivar was expressed
as percentage of necrosis in relation to entire length of shoot, and the ranking of cultivars in 2009 and 2010 was compared
with a Spearman rank correlation test, P < 0.01. A relationship between presence of both flanking marker alleles for tolerance and level of fire blight tolerance
was confirmed with a Mann–Whitney U-test, P < 0.01 in 2009, and P < 0.05 in 2010. A PCO (principal coordinate) analysis based on band profiles obtained with 12 SSR (simple sequence repeat)
loci produced three loose clusters, two of which contained known offspring of ‘Cox’s Orange Pippin’, and one with cultivars
that were either unrelated or had an unknown origin. Cases where DNA markers did not predict level of fire blight damage as
expected, were, however, as common among descendants of ‘Cox’s Orange Pippin’ as among apparently unrelated cultivars. Obviously
the ‘Fiesta’ LG 7 QTL has some predictive value, both for known ‘Cox’ relatives and others, but more efficient markers would
be desirable for marker-assisted selection. 相似文献
10.
The purpose of this paper is to investigate the differential responses of flower opening to ethylene in two cut rose cultivars,
‘Samantha’, whose opening process is promoted, and ‘Kardinal’, whose opening process is inhibited by ethylene. Ethylene production
and 1-aminocyclopropane-1-carboxylate (ACC) synthase and oxidase activities were determined first. After ethylene treatment,
ethylene production, ACC synthase (ACS) and ACC oxidase (ACO) activities in petals increased and peaked at the earlier stage
(stage 3) in ‘Samantha’, and they were much more dramatically enhanced and peaked at the later stage (stage 4) in ‘Kardinal’
than control during vasing. cDNA fragments of three Rh-ACSs and one Rh-ACO genes were cloned and designated as Rh-ACS1, Rh-ACS2, Rh-ACS3 and Rh-ACO1 respectively. Northern blotting analysis revealed that, among three genes of ACS, ethylene-induced expression patterns of
Rh-ACS3 gene corresponded to ACS activity and ethylene production in both cultivars. A more dramatic accumulation of Rh-ACS3 mRNA was induced by ethylene in ‘Kardinal’ than that of ‘Samantha’. As an ethylene action inhibitor, STS at concentration
of 0.2 mmol/L generally inhibited the expression of Rh-ACSs and Rh-ACO in both cultivars, although it induced the expression of Rh-ACS3 transiently in ‘Kardinal’. Our results suggests that ‘Kardinal’ is more sensitive to ethylene than ‘Samantha’; and the changes
of Rh-ACS3 expression caused by ethylene might be related to the acceleration of flower opening in ‘Samantha’ and the inhibition in
‘Kardinal’. Additional results indicated that three Rh-ACSs genes were differentially associated with flower opening and senescence as well as wounding. 相似文献
11.
Ying Li Yuping Song Gongjun Shi Jianjun Wang Xilin Hou 《Acta Physiologiae Plantarum》2009,31(1):155-162
Changes in ascorbic acid content and antioxidant enzyme activities were investigated in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) leaves of ‘Wutacai’ and ‘Erqing’ exposed to excess copper (Cu). Cu treatment reduced the fresh weight of shoot and
root by 57% and 46% in ‘Wutacai’, and 60 and 54% in ‘Erqing’, respectively. The accumulation of copper in leaves was higher
in ‘Wutacai’ than that in ‘Erqing’. Compared to the control, ascorbic acid (AsA) contents were significantly decreased after
copper treatment in both cultivars, while they were higher in ‘Wutacai’ than in ‘Erqing’, which may explain the higher copper-tolerance
of ‘Wutacai’ with higher copper accumulation. The higher AsA contents of ‘Wutacai’ resulted from their lower activities of
degrading enzymes, such as ascorbate oxydase (AAO) and ascorbate peroxidase (APX), as well as the increasing activity of dehydroascorbate
reductase (DHAR) after copper treatment compared with ‘Erqing’. Copper stimulated superoxide dismutase (SOD) activity in both
cultivars, but for catalase (CAT), there was little difference between both cultivars. Peroxidases (POD) activity was decreased
after copper treatment in ‘Erqing’, while in ‘Wutacai’, it was significantly increased at 14 days, and POD activity was higher
in ‘Wutacai’ than that in ‘Erqing’ at 21 and 28 days. Therefore, the induced increasing activity of POD in ‘Wutacai’ also
played an important role in its copper tolerance. 相似文献
12.
Localization of the rice stripe disease resistance gene, Stv-bi, by graphical genotyping and linkage analyses with molecular markers 总被引:4,自引:0,他引:4
Y. Hayano-Saito T. Tsuji K. Fujii K. Saito M. Iwasaki A. Saito 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(8):1044-1049
We used graphical genotyping and linkage analyses with molecular markers to determine the chromosomal location of the rice
stripe disease resistance gene, Stv-b
i
. The stripe resistance gene from the indica rice (Oryza sativa) cv ‘Modan’ was introgressed into several Japanese rice varieties. We found 4 RFLP markers in ‘Modan’, five susceptible parental
rice varieties (‘Norin No. 8’, ‘Sachihikari’, ‘Kanto No. 98’, ‘Hokuriku No.103’ and ‘Koganebare’) and four resistant progeny
varieties (‘St. No. 1’, ‘Aichi No. 6’, ‘Aoisora’ and ‘Asanohikari’). Graphical genotyping of the resistant progeny revealed
a chromosomal segment ascribable to ‘Modan’ and associated with stripe resistance. The chromosomal segment from ‘Modan’ was
located at 35.85 cM on chromosome 11. Linkage analysis using 120 F2 individuals from a cross between ‘Koshihikari’ (susceptible) and ‘Asanohikari’ (resistant) revealed another 8 RFLP markers
in the same chromosome. We performed a bioassay for rice stripe resistance in F3 lines of the F2 individuals using infective small brown planthoppers and identified an 1.8-cM segment harboring the rice stripe disease resistance
gene, Stv-b
i
, between XNpb220 and XNpb257/ XNpb254. Furthermore, Stv-b
i
was linked by 0.0 cM to a RFLP marker, ST10, which was developed on the basis of the results of RAPD analysis. These DNA
markers near the Stv-b
i
locus may be useful in marker-assisted selection and map-based cloning of the Stv-b
i
gene.
Received: 26 September 1997 / Accepted: 4 November 1997 相似文献
13.
In recent years there has been significant progress in the development of attenuated Salmonella enterica serovar Typhi strains as candidate typhoid fever vaccines. In clinical trials these vaccines have been shown to be well tolerated and immunogenic. For example, the attenuated S. enterica var. Typhi strains CVD 908-htrA (aroC aroD htrA), Ty800 (phoP phoQ) and chi4073 (cya crp cdt) are all promising candidate typhoid vaccines. In addition, clinical trials have demonstrated that S. enterica var. Typhi vaccines expressing heterologous antigens, such as the tetanus toxin fragment C, can induce immunity to the expressed antigens in human volunteers. In many cases, the problems associated with expression of antigens in Salmonella have been successfully addressed and the future of Salmonella vaccine development is very promising. 相似文献
14.
V. V. Emelyanov 《Russian Journal of Bioorganic Chemistry》2000,26(9):532-538
Fragments of a gene for species-specific protective antigen SPA ofRickettsia prowazekii earlier cloned in λgt11 were recloned into the in-frame expression vector pQE30. Polypeptides encoded by these fragments
were shown to be synthesized inEscherichia coli with a yield of up to 100 μg/ml of culture and to be accumulated in the cells as inclusion bodies. The partially purified
antigens were used in enzyme immunoassay with the sera of humans convalescing from epidemic typhus, tick-borne rickettsioses,
and other infectious diseases. One of two recombinant proteins was shown to react in immunoblotting and ELISA with homologous,
but not with heterologous, sera. The immunoreactivities in ELISA of the recombinant antigens and heat-denatured SPA proved
to be similar, but substantially lower than that of the native SPA. These data as well as the data of other investigators
show that serodiagnostics of epidemic typhus using recombinant antigens remains a problem. 相似文献
15.
Aswin Mangerich Harry Scherthan Jörg Diefenbach Ulrich Kloz Franciscus van der Hoeven Sascha Beneke Alexander Bürkle 《Transgenic research》2009,18(2):261-279
Here we report an approach to generate a knock-in mouse model using an ‘ends-out’ gene replacement vector to substitute the
murine Parp-1 (mParp-1) coding sequence (32 kb) with its human orthologous sequence (46 kb). Unexpectedly, examination of mutant ES cell clones
and mice revealed that site-specific homologous recombination was mimicked in three independently generated ES cell clones
by bidirectional extension of the vector homology arms using the endogenous mParp-1-flanking sequences as templates. This was followed by adjacent integration of the targeting vector, thus leaving the endogenous
mParp-1 locus functional. A related phenomenon termed ‘ectopic gene targeting’ has so far only been described for ‘ends-in’ integration-type
vectors in non-ES cell gene targeting. We provide reliable techniques to detect such ectopic gene targeting which represents
an unexpected caveat in mouse genetic engineering that should be considered in the design and validation strategy of future
gene knock-in approaches.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
IgA-driven T cell-mediated anti-bacterial immunity in man after live oral Ty 21a vaccine 总被引:9,自引:0,他引:9
A Tagliabue L Villa M T De Magistris M Romano S Silvestri D Boraschi L Nencioni 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(5):1504-1510
Cellular immunity against Salmonella typhi was observed by using a direct anti-bacterial in vitro assay in volunteers orally vaccinated with the live S. typhi mutant strain Ty 21a. With this experimental approach, it was demonstrated that Ty 21a vaccine also induces cellular immunity against S. paratyphi A and B. Interestingly, the mechanism involved in cellular immunity against bacteria seems to be of an antibody-dependent cellular cytotoxicity (ADCC) type, with IgA acting as the humoral arm and CD4+ T lymphocytes as the cellular one. In accordance with the increase in IgA-driven ADCC against S. typhi, a major rise in IgA against O and H antigens was observed in the serum of vaccinees in parallel to an increase in IgG of identical specificity. Furthermore, a Ty 21 vaccine induced cellular activity against flagellar antigens. These results indicate that IgA-ADCC by T lymphocytes against bacteria can originate from local stimulation of the gut mucosal immune system. This cellular defense mechanism might be at the origin of the protection induced by Ty 21a vaccine. 相似文献
17.
We have developed a recombinant live oral vaccine using the ice-nucleation protein (Inp) from Pseudomonas syringae to display viral antigens on the surface of Salmonella spp. Fusion proteins containing viral antigens were expressed in the oral vaccine strain, Salmonella typhi Ty21a. Surface localization was verified by immunoblotting and fluorescence-activated cell sorting. The immunogenicity of surface-displayed viral antigens on the recombinant live vaccine strain was assessed in mice inoculated intranasally and intraperitoneally. Inoculation resulted in significantly higher serum antibody level than those induced by viral antigens expressed intracellularly. Thus, this multivalent mucosal live vaccine may provide an effective means for inducing mucosal or systemic immune responses against multiple viral antigens. 相似文献
18.
Costello MJ 《Experimental & applied acarology》2007,42(3):197-208
Sulfur is the oldest and most widely used fungicide in the vineyards of California, where it is used for control of powdery
mildew (Uncinula necator [Schw.] Burr). For decades, sulfur use has been associated with outbreaks of Tetranychus pacificus McGregor (Acari: Tetranychidae) on cultivated grapes in the San Joaquin Valley. I undertook large-scale field studies to
test this association, to evaluate the impact of sulfur on Galendromus occidentalis (Nesbit) (Acari: Phytoseiidae), a major predator of T. pacificus, and to determine if timing of sulfur applications with respect to grape bloom has an impact on T. pacificus density. The studies took place in a 32 ha vineyard in Fresno County, and all fungicide applications were made with commercial-scale
equipment. In 1998 a ‘high sulfur’ treatment, a combination of wettable sulfur and sulfur dust, was compared to ‘low sulfur,’
in which demethylation inhibitor (DMI) fungicides partially substituted for sulfur. In 1999 treatments were ‘sulfur,’ ‘DMI,’
‘sulfur pre-bloom’ (here sulfur was applied prior to grape bloom, in late May, and then DMIs were applied until mid-season)
and ‘sulfur post-bloom’ (the reverse of ‘sulfur pre-bloom’). In each year, the T. pacificus population increase came after the end of fungicide applications, and results clearly show a relationship between sulfur
use and T. pacificus density. In 1998, mean T. pacificus density was 2.7 times higher and mean G. occidentalis density 2.5 times higher in ‘high sulfur’ compared to ‘low sulfur.’ In 1999, the highest T. pacificus counts were in the ‘sulfur’ and ‘sulfur pre-bloom’ treatments, 4.8 times higher than ‘sulfur post-bloom’ and 2 times higher
than ‘DMIs.’ Density of G. occidentalis was 2.3 times as high in ‘sulfur’ or ‘sulfur pre-bloom’ than ‘DMIs.’ The predator/prey ratio was not significantly different
among treatments in 1998, but in 1999 it was highest in the ‘sulfur pre-bloom’ treatment. In 1999, density of Homeopronematus anconai (Baker) (Acari: Tydeidae) was 2.7 times higher in ‘sulfur pre-bloom’ compared to ‘sulfur,’ and higher by 2.7 times in ‘DMI’
compared to ‘sulfur post-bloom,’ suggesting a negative effect of sulfur on this tydeid. These results do not support the hypotheses
that the cause of the increase in T. pacificus density is due to negative effects of sulfur on phytoseiids or tydeids. Rather, it appears that a plant-based explanation
is likely, first, because of the differences in pre-bloom versus post-bloom sulfuring, and second, because of the long lag
time between the end of the sulfur applications and the corresponding increase in spider mite density. 相似文献
19.
Nutan Karnik H. Channaveerappa H. A. Ranganath Raghavendra Gadagkar 《Journal of genetics》2010,89(2):173-182
The queenless ponerine ant Diacamma ceylonense and a population of Diacamma from the Nilgiri hills which we refer to as ‘nilgiri’, exhibit interesting similarities as well as dissimilarities. Molecular phylogenetic study of these morphologically almost
similar taxa has shown that D. ceylonense is closely related to ‘nilgiri’ and indicates that ‘nilgiri’ is a recent diversion in the Diacamma phylogenetic tree. However, there is a striking behavioural difference in the way reproductive monopoly is maintained by
the respective gamergates (mated egg laying workers), and there is evidence that they are genetically differentiated, suggesting
a lack of gene flow. To develop a better understanding of the mechanism involved in speciation of Diacamma, we have analysed karyotypes of D. ceylonense and ‘nilgiri’. In both, we found surprising inter-individual and intra-individual karyotypic mosaicism. The observed numerical variability,
both at intra-individual and inter-individual levels, does not appear to have hampered the sustainability of the chromosomal
diversity in each population under study. Since the related D. indicum displays no such intra-individual or inter-individual variability whatsoever under identical experimental conditions, these
results are unlikely to be artifacts. Although no known mechanisms can account for the observed karyotypic variability of
this nature, we believe that the present findings on the ants under study would provide opportunities for exciting new discoveries
concerning the origin, maintenance and significance of intra-individual and inter-individual karyotypic mosaicism. 相似文献
20.
Maria M. van Dyk Mogamat Khashief Soeker Iwan F. Labuschagne David Jasper G. Rees 《Tree Genetics & Genomes》2010,6(3):489-502
In the Western Cape region of South Africa, dormancy release and the onset of growth does not occur normally in apple (Malus x domestica Borkh.) trees during spring due to the mild winter conditions experienced and fluctuations in temperatures experienced during
and between winters. In this region, the application of chemicals to induce the release of dormancy forms part of standard
orchard management. Increasing awareness of the environmental impact of chemical sprays and global warming has led to the
demand for new apple cultivars better adapted to local climatic conditions. We report the construction of framework genetic
maps in two F1 crosses using the low chilling cultivar ‘Anna’ as common male parent and the higher chill requiring cultivars
‘Golden Delicious’ and ‘Sharpe’s Early’ as female parents. The maps were constructed using 320 simple sequence repeats, including
116 new markers developed from expressed sequence tags. These maps were used to identify quantitative trait loci (QTL) for
time of initial vegetative budbreak (IVB), a dormancy related characteristic. Time of IVB was assessed four times over a 6-year
period in ‘Golden Delicious’ x ‘Anna’ seedlings kept in seedling bags under shade in the nursery. The trait was assessed for
3 years on adult full-sib trees derived from a cross between ‘Sharpe’s Early’ and ‘Anna’ as well as for 3 years on replicates
of these seedlings obtained by clonal propagation onto rootstocks. A single major QTL for time of IVB was identified on linkage
group (LG) 9. This QTL remained consistent in different genetic backgrounds and at different developmental stages. The QTL
may co-localize with a QTL for leaf break identified on LG 3 by Conner et al. (1998), a LG that was, after the implementation of transferable microsatellite markers, shown to be homologous to the LG now known
to be LG 9 (Kenis and Keulemans 2004). These results contribute towards a better understanding regarding the genetic control of IVB in apple and will also be
used to elucidate the genetic basis of other dormancy related traits such as time of initial reproductive budbreak and number
of vegetative and reproductive budbreak. 相似文献