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11.
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
12.
J. B. Clarke D. J. Sargent R. I. Bošković A. Belaj K. R. Tobutt 《Tree Genetics & Genomes》2009,5(1):41-51
One hundred and sixty microsatellite (simple sequence repeat (SSR)) and six gene-specific markers revealing 174 loci were
scored in 94 seedlings from the inter-specific cross of Prunus avium ‘Napoleon’ × Prunus nipponica accession F1292. The co-segregation data from these markers were used to construct a linkage map for cherry which spanned
680 cM over eight linkage groups with an average marker spacing of 3.9 cM per marker and just six gaps longer than 15 cM.
Markers previously mapped in Prunus dulcis ‘Texas’ × Prunus persica ‘Earlygold’ allowed the cherry map to be anchored to the peach × almond map and showed the high level of synteny between
the species. Eighty-four loci segregated in P. avium ‘Napoleon’ versus 159 in P. nipponica. The segregations of 32 isoenzyme loci in a subset of 47 seedlings from the progeny were scored, using polyacrylamide gel
electrophoresis and/or isoelectric focusing separation followed by activity staining, and the co-segregation data were analysed
along with those for 39 isoenzymes reported previously and for the 174 sequence-tagged site loci plus an additional two SSR
loci. The second map incorporates 233 loci and spans 736 cM over eight linkage groups with an average marker spacing of 3.2 cM
per marker and just two gaps greater than 15 cM. The microsatellite map will provide a useful tool for cherry breeding and
marker-assisted selection and for synteny studies within Prunus; the gene-specific markers and isoenzymes will be useful for comparisons with maps of other rosaceous fruit crops.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
13.
白刺珠心组织及其营养功能的超微结构观察 总被引:1,自引:0,他引:1
白刺具厚珠心,珠心组织发达。原胚期,根据超微结构特征,珠心组织大体可区分为三层:外围不活跃细胞层、特化细胞层和胚囊外围解体细胞层。珠心细胞解体时,细胞壁首先以微纤丝状态分散,原生质不同程度破坏,并累积脂滴。近胚囊壁降解后,珠心细胞即成为开放细胞,原生质团游离到胚囊周围。胚囊壁在珠孔区和合点区间断,因之,珠心细胞的游离原生质团可直接迁入胚囊内。在胚囊壁和中央细胞质膜之间存在明显间隙区域,其中有大量壁旁体存在,是珠心细胞降解物质进入胚囊的另一重要途径。 相似文献
14.
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
15.
伤处理和乙烯对桃ACC氧化酶基因表达的影响 总被引:2,自引:0,他引:2
桃果实不耐贮运,特别是溶质水蜜桃、珐I大11_程技术的发展使番茄果实实现延熟保鲜'-'、人f[]也试图通过乙烯合成的关键酶的]i义HNA技术来延长桃果实的贮运期。:ICC氧化酶是乙烯生物合成的关键酶之一,ACC氧化酶4peJL从番茄'、矮牵牛。。。桃卜'、苹果、'等许多植物... 相似文献
16.
Criconemella xenoplax, Fusarium solani, and F. oxysporum caused necrosis of Nemaguard peach feeder roots in greenhouse tests. Root necrosis was more extensive in the presence of either fungus than wtih C. xenoplax alone. Shoot growth and plant height were less for plants inoculated with F. oxysporum or F. solani than for plants inoculated with the fungi plus C. xenoplax. Neither synergistic nor additive effects on root necrosis or plant growth occurred between C. xenoplax and the fungal pathogens. 相似文献
17.
2010年9月至2013年4月通过设置人工土壤种子库,研究了野生樱桃李土壤种子库的动态及啮齿动物和凋落物覆盖对种子库中种子命运的影响.结果表明: 在有取食动物扰动下,48.3%的种子萌发输出为幼苗,50%的种子被动物搬运或当场取食,4%的种子腐烂.在排除了取食动物干扰的条件下,樱桃李种子形成了短期持久的土壤种子库,3年后依然有部分种子萌发并输出为幼苗.凋落物覆盖和对照处理中,被搬运和当场取食种子的比例均显著低于清除凋落物的裸地.地表凋落物存留能减少动物搬运、取食,但不足以导致新生幼苗的大量出现,而啮齿类动物的搬运或取食是影响野生樱桃李种子命运和种子库动态的主要因素.
相似文献
18.
Elsa Desnoues Michel Génard Bénédicte Quilot‐Turion Valentina Baldazzi 《The Plant journal : for cell and molecular biology》2018,94(4):685-698
The concentrations of sugars in fruit vary with fruit development, environment and genotype. In general, there were weak correlations between the variations in sugar concentrations and the activities of enzymes directly related with the synthesis or degradation of sugars. This finding suggests that the relationships between enzyme activities and metabolites are often non‐linear and are difficult to assess. To simulate the concentrations of sucrose, glucose, fructose and sorbitol during the development of peach fruit, a kinetic model of sugar metabolism was developed by taking advantage of recent profiling data. Cell compartmentation (cytosol and vacuole) was described explicitly, and data‐driven enzyme activities were used to parameterize equations. The model correctly accounts for both annual and genotypic variations, which were observed in 10 genotypes derived from an interspecific cross. They provided important information on the mechanisms underlying the specification of phenotypic differences. In particular, the model supports the hypothesis that a difference in fructokinase affinity could be responsible for a low fructose‐to‐glucose ratio phenotype, which was observed in the studied population. 相似文献
19.
珍稀濒危植物蒙古扁桃的组织培养及植株再生 总被引:12,自引:2,他引:12
对珍稀濒危植物蒙古扁桃进行组织培养获得再生植株。实验结果表明,在MS培养基上蒙古扁桃幼苗茎尖,茎切段和叶片等外植体均可以脱分化形成愈伤组织,并进一步分化形成再生植株。器官的脱分化与再分化决定于培养基中的激素种类及其浓度。诱导愈伤组织形成的最适培养基为MS+6-BA0.8mg/L NAA0.1mg/L,芽分化诱导最适培养基为MS+6-BA0.8mg/L,诱导生根的最适培养基是MS+IBA0.5mg/L。 相似文献
20.
Hideki Endo Hiroyuki Sasaki Yoshihiro Hayashi Evageny A. Petrov Masao Amano Nobuyuki Miyazaki 《Marine Mammal Science》1998,14(4):778-788
This study was performed to determine if, as expected, the enlarged eye of the Baikal seal ( Phoca sibirica ) has an influence on the form and function of the skull and facial muscles. Macroscopic observation of these muscles demonstrated that the M. orbicularis oculi expands around the palpebral fissure and that some facial muscles attach and insert in the M. orbicularis oculi , possibly supporting M. orbicularis oculi function. We suggest that these muscles move the eye and palpebral area and constitute a morphological and synergistic facial muscle complex system. Further, the development of the M. rectus lateralis around the sclera of the eye indicates that this muscle is also involved in eye movement. 相似文献