摘要:

Proline stimulates proliferation of callus and somaclonal variation, particularly albino regeneration, in rice tissue culture under high osmosis. Albino regenerants from scutellum-derived callus exhibited various deletion patterns in chloroplast DNA, similar to those reported in anther-derived albino regenerants. Through differential display one PCR product was selected which showed enhanced expression by proline in scutellum-derived callus. Northern blot analysis revealed a 2.6 kb major transcript. A deduced amino acid sequence of a partial cDNA clone (976 b) selected from a cDNA library constructed from proline-treated callus showed 36% homology with a maize protein (MURA) encoded by an autonomous regulatory transposable element MuDR. A rice homologue to maize MuDR (designated as Os-MuDR) was shown to be present as a single copy gene in Japanese rice cultivars. Our results suggest a possible relationship between Os-MuDR and the high frequency of somatic mutations including albino regeneration in rice tissue culture.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818956

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

The 130 kD crystal protein coded on Cry 1Ab from Bacillus thuringiensis ssp.aizawai is highly insecticidal against Plutella xylostella larvae and less toxic to Spodoptera litura larvae. The mutant with triple amino acid replacements at Arg619, Lys622and Lys637with Gin was 2.5 times more active against S. litura than the wild type protein. The truncated mutant and wild type cry 1Ab genes coding for the first 647 amino acids were each placed under the control of CaMV 35S promoter and Nos terminator in a binary vector, and were transformed into a haploid clone of N. tabacum cv. Samson nn via Agrobacterium. Presence of the transgene in the genomic DNA of tobacco plants was confirmed by PCR and Southern blot. Insecticidal activity of the transgenic plants was examined by infesting freshly hatched S. litura larvae on leaf disks from in vitro grown plants. The biotests showed enhanced protection of the transgenic tobacco plants expressing each of the mutant and wild type Cry 1Ab protein compared to the untransformed control. However, the expression level of the Cry 1Ab active fragment in the leaf tissue was below the detection limit by Western blot even in the plants with the highest insecticidal activity. RT-PCR experiments revealed splicing of cry 1Ab genes at cryptic splicing sites which could not be predicted by sequence analyses.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818957

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

A toxin substance of Phytophthora parasitica var. nicotianae with 67kD Mw was purified from culture filtrate of the pathogen. The toxin was shown to have host specific toxicity in detached leaf bioassay at cultivar level. A ELISA system with polyclonal antibodies was established to quantify the toxin. The quantity of the toxin in the culture filtrate increased to the sixteenth day during the cultivation in the determinated conditions.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818958

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

A non-targeted transposon tagging experiment was performed in tomato (Lycopersicon esculentum). The Ac/Ds transposon system from maize was used. To generate a transposon tagging population, tomato genotypes ET 570 and SLJ10512 were used. The ET 570 genotype contains a single homozygous T-DNA with Ds at the end of the long arm of chromosome 3. The SLJ10512 genotype carries a stabilized Ac that can activate Ds in trans. This tagging population was tested at the seedling level (Van der Biezen et al., 1996) and two phenotypic mutants were found that co-segregated with a Ds insertion: feebly (fb) and yellow jim (yj). In this work, performed under field conditions, all stages of individual plant development were screened for mutant phenotypes. Out of 269 families, with in total approximately 400 unique transposed Ds elements, 5 different phenotypes were observed. One of the phenotypes, fruit distortion, segregated in a Mendelian fashion. Plants with the fruit distortion phenotype did not produce seeds. In the case of the other 4 phenotypes, green spots, dark green leaves, dwarf and partially hairless plant only one phenotypic mutant plant per family was obtained and, thus, could not be classified. Phenotypic mutants, obtained from this transposon tagging experiment, that show linkage to the Ds insertion, might be used to isolate the genes responsible for the mutant phenotypes.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818959

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

Transformations of potato (Solanum tuberosum cv. Yayla kizi) and tobacco (Nicotiana tabacum cv. Samsun NN) were achieved using tuber discs and internodes via Agrobacterium rhizogenes 8196 wild strain on MS (11) media supplemented with 5 μM Naphthalene Acetic Acid (NAA). In this study, we examined the effects of NAA on hairy root formation of potato and tobacco. Cultures of bacteria were concentrated at O.D.600=0.2 for inoculation and MS media supplemented with 1 μM Cefotaxime (Cx) and 5 μM NAA were used for co-cultivation. Transformed hairy roots were obtained after three weeks in a regulated plant growth cabinet at 25 °C with 16 hours light followed by 8 hours dark period. DNA was extracted from these roots and digested using EcoR I and Hind III restriction endonucleases, and transformation was confirmed using the Southern blot hybridization method with [γ32P] CTP labeled Ri plasmid DNA of A. rhizogenes 8196.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818960

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

The identification of six Turkish tobacco cultivars was done according toperoxidase,malatedehydrogenaseandesteraseizosyme banding patterns using Polyacrylamide gel electrophoresis (PAGE) method. Different extraction methods were applied to fresh leaves from the plants at different growing stages. The best result was obtained from the leaves at the flowering stage using the extraction method of Moore G. A., et al. PAGE was carried out with 400E Hoeffer vertical slab gel apparatus, according to Davis (1964). Extraction buffer consisted of 5mM Na2EDTA, 0.25 M NaCl, 0.05 M NaHSO3and 0.025M β-Mercaptoethonol in a 0.05 M Tris—HCl buffer pH 8.0. Electrot buffer: Tris 5 mM, Glisin 38.5 mM pH 8.3. Varieties differed with regard to their PER and EST izosyme banding patterns but no qualitative differences were detected in MDH bands.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818961

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

The specific in vitro conditions cause a modified structure and physiological functions of the photosynthetic apparatus which result in poor survival rate of plantlets during acclimatization. The type of vessel closure affects the gaseous composition and hence affects the growth of plantlets in culture. In tightly closed vessels concentrations of metabolically generated gases increase because their rate of diffusive escape is depressed. Different approaches have been proposed to enhance the photosynthetic ability of plants in vitro in striving to favour the success of further acclimatization to conditions ex vitro. The aims of the present research are to find the closure material which is gas permeable and to study the effect of the improved gas exchange on the growth and the photosynthetic ability of the micropropagated apple rootstock MM 106. The polyester wool—one of the tested types of closure, provides good gas exchange rate and preserves the culture from contamination. The data of this investigation show that there is a positive correlation between the improved gas exchange and accumulation of dry matter, light harvesting pigments as well as the ability of plantlet to assimilate14CO2. In plantlets, cultured with polyester wool, the relative part of the labelled low -molecular photosynthetic products (sugars, amino acids, organic acids) decreases, while the part of labelled high-molecular fractions (lipids, pigments and starch) increases. The improvement of gas exchange leads to rise of the content of sorbitol and the ratio sorbitol: saccharose. This might be a sign of a better carbon metabolism of in vitro cultivated apple root-stock MM 106.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818962

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818963

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

Water solutions of some plant growth regulators as malzit special—potassium salt of the hydrazid of maleinic acid, pirocathechol and methyl ester of itaconic acid were tested in sugar-beet storage. Beets were treated after harvest and then stored for 20 days and analyzed. The growth regulators applied suppressed the invertase activity and this reflected in a better storage of the beets. The influence of methyl ester of itaconic acid was weakly expressed in comparison with the effects of the potassium salt of the hydrazid of maleinic acid and of pirocatechol but methyl ester of itaconic acid presented a special interest for biothechnology becouse of its low extent of toxicity.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818964

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor

摘要:

Immature embryos of common oak (Q. robur L.) were used as initial explants for inducing the process of somatic embryogenesis. The best embryogenic response (53.3%) was registered on MS medium supplemented with either 1.0 mg/l BAP alone or in combination with 1.0 mg/l GA3. The embryos collected during the first week of July demonstrated highest embryogenic competence that rapidly decreased and got lost by the end of the period tested. Embryogenic cultures could be easily maintained in darkness by regular transfers on hormone-free MS medium. Some mature somatic embryos successfully germinated after being transferred to WPM medium with 0.2 mg/l BAP. Such embryos showed further development and converted into plantlets.

ISSN:1310-2818    

DOI:10.1080/13102818.1998.10818965

出版商:Taylor & Francis    

年代:1998

数据来源: Taylor