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71.
F. A. Hammerschlag G. Bauchan R. Scorza 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,70(3):248-251
Summary Peach plants were repeatedly regenerated from immature embryos but not from callus derived from mature embryos. A white, nodular, highly regenerative callus was obtained when friable, primary callus from immature embryos was transferred from medium containing 4.5 M 2,4-dichlorophenoxyacetic acid and 0.44 M benzyladenine (BA) to media containing 0.27 M -naphthaleneacetic acid (NAA) and 2.2 M BA. This callus retained its morphogenetic potential for a minimum of three subcultures. Green nodular callus, that lacked regenerative capacity, was produced from primary callus derived from mature embryos. Maximum regeneration of shoots occurred when highly regenerative callus was transferred to a medium in which the NAA concentration was reduced five times and the BA concentration was increased two times. Regenerated shoots were rooted in the dark on a medium containing 28.5 M indoleacetic acid. Cytogenetic analysis of regenerated plants indicated that all plants were diploid, 2n = 2x = 16. Phenotypic evaluation of regenerated plants, grown under field conditions, is now in progress. 相似文献
72.
Dimethylsulfoxide (DMSO) was found to be an efficient solvent for extraction of Coomassie Blue R 250 (Coomassie R) from stained proteins on polyacrylamide gels. Kinetic measurements show that the extraction of the dye from a 2-D gel reached equilibrium in 48 h. Staining of E. coli ribosomal proteins by Coomassie R dissolved in trichloroacetic acid exhibited two types of dye-protein complexes, the majority of them yield a blue-purple colour, while the rest are stained with a light-blue tone and fluorescent appearance as well. The absorbance spectra of the complexes in the gel matrix differ significantly from each other. However, the DMSO-extracted Coomassie show identical absorbance profiles with lambda max at 602 nm, thus the amount of the bound dye can easily be measured spectrophotometrically. 相似文献
73.
Hoekema A. van Haaren M. J. J. Fellinger A. J. Hooykaas P. J. J. Schilperoort R. A. 《Plant molecular biology》1985,5(2):85-89
Summary
Agrobacterium strains harbouring the T-region and the virulence-region of the Ti plasmid on separate replicons still display efficient T-DNA transfer to plants. Based on this binary vector strategy we have constructed T-region derived gene vectors for the introduction of foreign DNA into plants. The vectors constructed can replicate in E. coli, thus the genetic manipulations with them can be performed with E. coli as a host. They can be transferred to Agrobacterium as a cointegrate with the wide host range plasmid R772. Their T-regions are transferred to plant cells from Agrobacterium strains conferring virulence functions.The plasmid pRAL 3940 reported here is 11.5 kb large, contains a marker to identify transformed plant cells and unique restriction sites for direct cloning of passenger DNA, flanked by the left- and right-hand border fragments of the T-region (including the 25 bp border repeats). The plasmid is free of onc-genes. Therefore, is does not confer tumorigenic traits on the transformed plant cells and mature, fertile plants can thus be regenerated from them. 相似文献
74.
The genomic sequences of several RNA plant viruses including cucumber mosaic virus, brome mosaic virus, alfalfa mosaic virus
and tobacco mosaic virus have become available recently. The former two viruses are icosahedral while the latter two are bullet
and rod shaped, respectively in particle morphology. The non-structural 3a proteins of cucumber mosaic virus and brome mosaic
virus have an amino acid sequence homology of 35% and hence are evolutionarily related. In contrast, the coat proteins exhibit
little homology, although the circular dichroism spectrum of these viruses are similar. The non-coding regions of the genome
also exhibit variable but extensive homology. Comparison of the brome mosaic virus and alfalfa mosaic virus sequences reveals
that they are probably related although with a much larger evolutionary distance. The polypeptide folds of the coat protein
of three biologically distinct isometric plant viruses, tomato Bushy stunt virus, southern bean mosaic virus and satellite
tobacco necrosis virus have been shown to display a striking resemblance. All of them consist of a topologically similar 8-standard
β-Barrel. The implications of these studies to the understanding of the evolution of plant viruses will be discussed. 相似文献
75.
J. P. Lewis Marta B. Collantes E. F. Pire Nélida J. Carnevale Silvia I. Boccanelli Susana L. Stofella D. E. Prado 《Plant Ecology》1985,60(2):67-90
This paper is a survey of the vegetation of the southeastern departments in the Province of Santa Fe (Argentina). The vegetation was analyzed following Braun-Blanquet's approach modified by Mueller-Dombois & Ellenberg (1974). The most relevant species of the region were placed in 25 groups according to their requirements or general behaviour. Most of the communities are herbaceous, and apart from the woody and some other miscellaneous ones they were grouped into three ecologically and floristically defined sets. The first set, the Stipa grasslands and related communities, which are characterized by the more or less abundant presence of Stipa hyalina, Stipa neesiana and Stipa papposa, comprises five different communities. The second, the halophilous communities, comprises five communities, the two Spartina ssp. grasslands, the halophilous prairies of Distichlis spicata, the short sedge Scirpus americanus communities and the ‘pela-dales’. The third, the hygrophilous communities, comprises nine communities which are not so well defined as the ones in the other sets. Besides, two further communities have been included, the Paspalum quadrifarium and the Melica macra tall grasslands. 相似文献
76.
“同时蒸馏-萃取”分析茉莉花香成分 总被引:5,自引:0,他引:5
用一种经过改进的“同时蒸馏-萃取”仪提取了茉莉花的香成分,以 GC/MS 和 Kovats保留指数法鉴定了提取物中的28个化学成分。主要成分为:芳樟醇、乙酸苯甲酯、顺-石竹萜烯、榧烯醇、苯甲酸顺-3-己烯酯、邻氨基苯甲酸甲酯、二十三烯-11及吲哚。讨论了鲜花香成分和植物精油的采集与分析方法。 相似文献
77.
Evidence from morphology and anatomy (including embryology), as well as from palynology, chemistry and cytology, indicates
thatHydrastis is quite divergent from Ranunculaceae (in which the genus has been most often included) as well as from both Glaucidiaceae
and Berberidaceae. Distinctive features ofHydrastis, which demarcate it from Ranunculaceae but which are sometimes shared by Berberidaceae, are: the unique mode of origin of
the vascular supply to stamens and carpels; the micropyle being formed by both integuments; the xylem not V-shaped in cross
section; scalariform vessel perforations present; haploid chromosome number 13; pollen tectum consisting of a compound layer
of striae; leaf mesophyll not differentiated; the unique course of stem medullary bundles; D-galactose present. Its distinctive
higher haploid chromosome number, as well as its many less-specialized character states (in floral structure, leaf anatomy,
and xylem and vessel morphology), suggest thatHydrastis is a relictual primitive group which diverged early from a common ancestral stock of Ranunculaceae, Berberidaceae and probably
of Circaeasteraceae; at least some of the features shared byHydrastis and one or another of the families concerned seem to be a heritage from their common ancestor. We propose a reestablishment
of a monotypic family, Hydrastidaceae. 相似文献
78.
79.
植物细胞的遗传全能性与组织培养形态发生控制 总被引:7,自引:0,他引:7
引言自1902年德国植物学家Haberlandt提出植物的单个细胞可能具有分化的全能性的理论以来,人们才开始从事植物组织培养,以致今天广泛用来有意识地定向控制遗传变异和人工创造植物新类型的研究。到今据不完全统计,全世界约有1000种高等植物作过离体培养尝试。根据大量实验结果证明,植物单个细胞具有遗传的全能性, 相似文献
80.
Climate and plant distribution at global and local scales 总被引:12,自引:0,他引:12
This paper investigates, with predictive models, the utility of ecophysiological responses to climate as predictors of plant distribution. At the global scale responses to extreme minimum temperatures and to the hydrological budget effectively predict the distribution limits of the major vegetation types of the World. A minimum temperature of -15°C, for example, appears critical in controlling the poleward spread of vegetation that is dominated by evergreen broadleaved species; however, the presence or absence of more frost resistant species, such as those that are deciduous broadleaved, is not obviously explained in terms of extremes of climate. In such cases, predicting the competitive relationships between species is necessary and dependent on the climatic sensitivity of population dynamics.We are grateful to Hans de Kroon for discussions on the application of matrices to ecology. 相似文献