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31.
Wünsch A Hormaza JI 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(2):299-305
Gametophytic self-incompatibility (GSI) in sweet cherry is determined by a locus S with multiple alleles. In the style, the S-locus codifies for an allele-specific ribonuclease (S-RNase) that is involved in the rejection of pollen that carries the same S allele. In this work we report the cloning and genomic DNA sequence analysis including the 5 flanking regions of four S-RNases of sweet cherry (Prunus avium L., Rosaceae). DNA from the cultivars Ferrovia, Pico Colorado, Taleguera Brillante and Vittoria was amplified through PCR using primers designed in the conserved sequences of sweet cherry S-RNases. Two alleles were amplified for each cultivar and three of them correspond to three new S-alleles named S
23
, S
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and S
25 present in 'Pico Colorado', 'Vittoria' and 'Taleguera Brillante' respectively. To confirm the identity of the amplified fragments, the genomic DNA of these three putative S-RNases and the allele S
12
amplified in the cultivar Ferrovia were cloned and sequenced. The nucleotide and deduced amino-acid sequences obtained contained the structural features of rosaceous S-RNases. The isolation of the 5-flanking sequences of these four S-RNases revealed a conserved putative TATA box and high similarity among them downstream from that sequence. However, similarity was low compared with the 5-flanking regions of S-RNases from the Maloideae. S
6
- and S
24
-RNase sequences are highly similar, and most amino-acid substitutions among these two RNases occur outside the rosaceous hypervariable region (RHV), but within another highly variable region. The confirmation of the different specificity of these two S-RNases would help elucidate which regions of the S-RNase sequences play a role in S-pollen specific recognition.Communicated by H.F. Linskens 相似文献
32.
Splitting of fruits is a function of two-dimensional tension caused by different growth rates of tissues and turgor, especially water uptake shortly before harvest. In order to analyse the mechanical properties of spheroid plant material close to stress-strain conditions in vivo, a new hydraulic two-dimensional testing device was set up. Sweet cherry (Prunus avium L.) fruit skin was chosen as a model system. The recorded pressure-deflection curves were non-linear, with a considerable initial "lag phase" and a distinct increasing end part. Taking into account the special geometry, these curves could be modelled with a newly developed analytical approach based on linear elastic material behaviour. The results demonstrated good correlation if a modulus of elasticity ranging from 160 to 250 MPa for the cherry fruit skin was chosen. In addition, a mean strength value of 47 MPa was calculated based on the theory of thin shells and spheres. The results are compared with mechanical data found for fruits and other plant material. In order to test the theoretical approach, two- and one-dimensional tension tests were performed on packaging PE foil, revealing a mean modulus of 171 MPa in bi-axial tension, and 193 and 242 MPa in uni-axial tension, depending on the test speed. The results demonstrate that it seems to be feasible to use this method to analyse the two-dimensional stress-strain conditions of spheroid plant materials such as cherry fruit skins. It may be applied as a tool for crop testing to elucidate the mechanical basis of cracking susceptibility of fruits. 相似文献
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35.
Grazia?MarinoEmail author Valentina?Ferrarini Silvia?Giardini Bruno?Biavati 《In vitro cellular & developmental biology. Plant》2003,39(3):327-331
Summary Use of lysozyme was tested for treatment of bacterial contaminations in in vitro shoot cultures of quince (Cydonia oblonga) ‘BA 29’ and the hybrid (Prunus persica × P. amygdalus) rootstock ‘GF 677’. Shoots which had been contaminated for about 1 yr by Bacillus circulans and Sphingomonas paucimobilis were treated in liquid culture, at pH 4.5, with 9–36 mg ml−1 egg white lysozyme (EWL), and compared to each other and to untreated cultures for their growth, proliferation, and number
of bacterial colony-forming units in the tissues. EWL did not negatively affect shoot growth up to 18 mg ml−1; furthermore, the proliferation rates of EWL-treated shoots were sometimes higher than those of controls. In contrast, the
concentration of 36 mg ml−1 had some deleterious effect on the regrowth capacity and shoot production of ‘GF 677’ at the first subculture to solid medium
after EWL, treatments. EWL had a simple bacteriostatic effect against Sphingomonas paucimobilis; in contrast, it was effective at 18 mg ml−1 in eliminating Bacillus circulans in both ‘BA 29’ and ‘GF 677’ cultures, after optimal treatment duration. 相似文献
36.
Plant genome archaeology: evidence for conserved ancestral chromosome segments in dicotyledonous plant species 总被引:3,自引:0,他引:3
Dominguez I Graziano E Gebhardt C Barakat A Berry S Arús P Delseny M Barnes S 《Plant biotechnology journal》2003,1(2):91-99
We have developed genetic maps, based on expressed sequence tags (ESTs) that are homologous to Arabidopsis genes, in four dicotyledonous crop plant species from different families. A comparison of these maps with the physical map of Arabidopsis reveals common genome segments that appear to have been conserved throughout the evolution of the dicots. In the four crop species analysed these segments comprise between 16 and 33% of the Arabidopsis genome. Our findings extend the synteny patterns previously observed only within plant families, and indicate that structural and functional information from the model species will be, at least in part, applicable in crop plants with large genomes. 相似文献
37.
Ainsley Phillip J. Hammerschlag Freddi A. Bertozzi Terry Collins Graham G. Sedgley Margaret 《Plant Cell, Tissue and Organ Culture》2001,67(3):221-226
Adventitious shoots were regenerated from immature cotyledons of four almond cultivars (`Ne Plus Ultra', `Nonpareil', `Carmel' and `Parkinson'). Open-pollinated fruit were collected from orchard-grown trees 100–115 days after full bloom. The proximal ends of the cotyledons were excised and the embryonic axes discarded. The effects of different concentrations of thidiazuron (TDZ) and indole-3-butyric acid (IBA) and the presence or absence of light for the first 7 days of culture were determined. Shoot regeneration rates were highest for cotyledons cultured for 8 weeks on Murashige and Skoog (MS) basal medium containing TDZ (10.0 M), followed by 4 weeks on medium without plant growth regulators. Regeneration levels were further improved if cotyledons were maintained in darkness for the first 7 days. IBA (0.5 M) significantly reduced the development of adventitious shoots. The frequency of cotyledons that developed adventitious shoots under the optimum tested conditions for `Ne Plus Ultra', `Nonpareil', `Carmel', and `Parkinson' were 80.0%, 73.3%, 100.0% and 86.7%, respectively. 相似文献
38.
R. Socias i Company 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(5):588-601
The large size and the long generation time of fruit trees generally reduce the possibilities of obtaining genetic information
on the transmission and heritability of useful agronomic traits in these species. However, from breeding work carried out
with fruit trees, an important amount of data is now available, although large differences are apparent among the different
species. There is not much information known about almond compared to what is available on other Prunus fruit species, but more data have been accumulated on it than on most of the other nut trees, thus making almond special
among all the temperate fruit and nut species. Only five qualitative traits have been described in almond, with an additional
two also possibly qualitative. Heritabilities have been estimated for an important number of quantitative traits, mainly phenological
times and fruit characters. Important information is available on molecular markers, including enzymes, RFLPs, RAPDs and other
recently developed markers. Linkages, however, have only been established among molecular markers, allowing accurate genetic
maps to be built but not yet enabling agronomical characters to be located in these maps, probably because the latter have
not been sufficiently studied. The effectiveness of the application of genetic maps in plant breeding will depend on the accuracy
of the study of different agronomic traits and their expression, implying more field work and recognition of this work. Ultimately,
any new fruit cultivar has to be grown in the field and has to allow the grower to make a profit.
Received: 1 June 1997 / Accepted: 1 September 1997 相似文献
39.
In many plant species with multiovulate ovaries, a considerable reduction in the number of ovules takes place. However, the
underlying physiological causes are not clear. In Prunus spp., although flowers present two ovules, usually only one seed is produced. We have followed the development and degeneration
of the two ovules in apricot (Prunus armeniaca L.) and examined the extent to which carbohydrates within the ovule might be involved in determining the fate of the ovule.
While the primary ovule grows in the days following anthesis, growth of the secondary ovule is arrested. Starch distribution
along the different ovular tissues exhibits several changes that are different in the two ovules. Primary ovule growth is
inversely related to starch content and this growth takes place independently of pollination since it occurs in the same way
in pollinated and unpollinated flowers. In the secondary ovule, starch disappears simultaneously from all ovular structures
and callose is layered at the chalazal end of the nucellus. The size of the secondary ovule does not change significantly
from anthesis to degeneration, and callose starts to accumulate 5 days after anthesis. Likewise, this process occurs independently
of pollination. These results are discussed in terms of the implications of the starch content of ovules in fertilization
success and ovule fate.
Received: 26 August 1997 / Revision accepted: 17 December 1997 相似文献
40.