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31.
32.
The feasibility of alternating use of resistant vs. susceptible flue-cured tobacco cultivars to improve control of Globodera tabacum subsp, solanacearum (TCN) was investigated at two Virginia locations in 1984-86. Post-harvest TCN population densities were reduced in each year of the study when fenamiphos was used with a TCN-resistant cultivar (NC 567), relative to susceptible cultivars (K 326 or Mc 944). Using NC 567 with fenamipbos also reduced preplant TCN population densities in the next growing season. Egg population densities before planting in 1986 were significantly lower in plots planted with NC 567 in 1984, even when a susceptible cultivar had been planted in 1985. Use of fenamiphos with NC 567 in 1984 and 1985 further reduced preplant egg population densities in 1986. Economic returns were significantly greater in 1984 when NC 567 was used with fenamiphos, rather than a susceptible cultivar. Treatments involving fenamiphos and (or) NC 567 in 1984 and 1985 resulted in higher economic returns in 1986 than did treatments using a susceptible cultivar without fenamiphos in both previous years. Economic returns were highest in 1986 when fenamiphos and NC 567 were used in 1984 and 1985 and a susceptible cultivar was planted in 1986. 相似文献
33.
Rémy Bitoun Philippe Rousselin Michel Caboche 《Molecular & general genetics : MGG》1990,220(2):234-239
Summary Mutant lines of Nicotiana plumbaginifolia resistant to the synthetic auxins 1-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) were isolated as germinating seedlings on selective medium. In each case, resistance was conferred by a single recessive nuclear mutation at one of 3 loci designated iba1, iba2 and iba3. Labelling studies with 14C NAA suggest that resistance was not due to changes in the uptake or metabolism of NAA. Plants homozygous for the iba1 mutation exhibit a syndrome of atypical germination and growth suggestive of a defect in the biosynthesis, metabolism or localization of abscisic acid. Wild-type seeds treated with gibberellin exhibit the same syndrome, including resistance to NAA and IBA. On the basis of these observations, we propose that auxin toxicity in seeds may be mediated by a block in gibberellin biosynthesis.Abbreviations ABA
abscisic acid
- GA
gibberellic acid
- IBA
indole-3-butyric acid
- NAA
1-naphthaleneacetic acid
- p-cell
protoplast-derived cell
- 2,4-D
2,4-dichlorophenoxyacetic acid 相似文献
34.
I. Negrutiu J. Dewulf M. Pietrzak J. Botterman E. Rietveld E. M. Wurzer-Figurelli De Ye M. Jacobs 《Physiologia plantarum》1990,79(1):197-205
Reports on direct gene transfer have dealt with either the obtention of stable transformants and transgenic plants, or described the use of reporter genes to analyse different aspects of gene expression in plant protoplasts and conditions for their use in transient gene expression assays.
In this paper we present comparisons between several transformation techniques, show species-specific differences in efficiencies of stable transformants and in the levels of transient gene expression, and report on the identification of major parameters responsible for DNA uptake as judged from transient chloramphenicol acetyl transferase (CAT) expression levels and from efficiencies of transformation based on kanamycin-resistance. The described procedures have been simplified, optimized and standardized and should allow routine use with a great variety of plant species. 相似文献
In this paper we present comparisons between several transformation techniques, show species-specific differences in efficiencies of stable transformants and in the levels of transient gene expression, and report on the identification of major parameters responsible for DNA uptake as judged from transient chloramphenicol acetyl transferase (CAT) expression levels and from efficiencies of transformation based on kanamycin-resistance. The described procedures have been simplified, optimized and standardized and should allow routine use with a great variety of plant species. 相似文献
35.
T. Komari 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(2):167-171
Summary A leaf-disk transformation experiment was performed with tobacco (Nicotiana tabacum L.) using a binary vector and a strain of Agrobacterium tumefaciens that carried a wild-type Ti-plasmid, pTiBo542. Although the majority of kanamycin-resistant, transgenic plants was morphologically normal, one of the plants was double-flowered and had a slightly wavy stem and leaves whose edges were bent slightly upwards. The abnormal morphology was controlled by a single, dominant Mendelian gene. Young plants that carried this gene were distinguishable from normal plants at the stage of cotyledons. The homozygotes, with respect to this gene, were more seriously deformed than the heterozygotes. DNA segments derived from the binary vector and from the TL-and TR-DNA of pTiBo542 were detected in the double-flowered plant, but the T-DNA genes involved in biosynthesis of phytohormones were absent from the plant. The abnormal morphology, the resistance to kanamycin, and the segments of foreign DNA were genetically linked, and the linkage was very tight, at least between the abnormal morphology and the resistance to kanamycin; the meiotic recombination frequency was less than 0.02%, if recombination occurred at all. 相似文献
36.
S. Toki T. Kameya T. Abe 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,80(5):588-592
Summary In order to produce a triple mutant, sexual crosses between a chlorophyll-deficient, streptomycin-resistant mutant of Nicotiana tabacum (SA) and a kanamycin-resistant transformant of N. tabacum (KR.) were carried out. From the offspring of this cross, a triple mutant (KR-SA) was selected. In N. tabacum KR-SA, chlorophyll deficiency is due to recessive mutation in the nuclear genome, streptomycin resistance is due to a dominant mutation in the chloroplast genome, and kanamycin resistance is shown to be a dominant nuclear marker. Cell suspension protoplasts of N. tabacum KRSA were fused with callus protoplasts of Solanum melongena by dextran treatment. Somatic hybrid plants were selected for streptomycin resistance and the ability to produce clorophyll in regenerated plants. By using this selection system, green plants were recovered from two colonies. When these green plants were then tested for kanamycin resistance, all analyzed plants carried this trait. In addition, the hybrid nature of these plants was confirmed by investigation of the peroxidase isozyme. The present results show that the use of N. tabacum KR-SA in studies of somatic hybridization makes it possible to select somatic hybrid plants easily and provides information of the N. tabacum genome.Chemical Regulation of Biomechanism, The Institute of Physical and Chemical Research, Wako 351-01, Japan 相似文献
37.
Zora Svab Elisabeth C Harper Jonathan D. G. Jones Pal Maliga 《Plant molecular biology》1990,14(2):197-205
The bacterial gene aad A encodes the enzyme aminoglycoside-3-adenyltransferase that confers resistance to spectinomycin and streptomycin in Escherichia coli. Chimeric genes have been constructed for expression in plants, and were introduced into Nicotiana tabacum by Agrobacterium binary transformation vectors. Spectinomycin or streptomycin in selective concentrations prevent greening of N. tabacum calli. Transgenic clones, however, formed green calli on selective media containing spectinomycin, streptomycin, or both drugs. Resistance was inherited as a dominant Mendelian trait in the seed progeny. Resistance conferred by the chimeric aad A gene can be used as a color marker similar to the resistance conferred by the streptomycin phosphotransferase gene to streptomycin. 相似文献
38.
At all stages of male gametogenesis, generative and vegetative pollen nuclei of Nicotiana sylvestris can be distinguished without ambiguity after Feulgen or ethidium bromide staining. They differ by their morphology and their apparent DNA content, always lower in vegetative nuclei. These differences provide a basis for their separation by sedimentation and fluorometry. After elimination of the another somatic cells and after crushing the pollen, vegetative and generative nuclei are separated by two successive Percoll gradients (purity 80–90%). Analysis of the gradient fractions and final purification can be done with a cell sorter. DNAs of both types are isolated by a cetyltrimethylammonium method, followed by a RNase treatment. Yields are lower for vegetative than for generative nuclei, and decrease with the age of pollen. Molecular weights and digestibility by restriction enzymes are compatible with molecular analyses. 相似文献
39.
利用BA-Sepharose 4B亲和层析技术丛白百利烟草(Nicotiana tabacum Baibaili)愈伤组织细胞分离提纯了分子量为4400±100道尔顿的细胞分裂素结合蛋白(CB-蛋白)。在细胞表面、核糖体、线粒体、叶绿体和细胞核上以及在细胞液中都有CB-蛋白存在,而核糖体上的CB-蛋白含量量高。探讨了CB-蛋白的功能。 相似文献
40.