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2.
研究表明,三属杂种处于单核中晚期阶段的花粉最适于诱导形成愈伤组织。低温预处理对促进三属杂种花粉愈伤组织的诱导有一定的作用。利用以马铃薯提取物为基础物质的马铃薯-Ⅱ培养基作诱导培养基,其愈伤组织诱导与分化的频率比目前两个较好的合成培养基要高。同一个三属杂种F_1春、秋播种植株之间在形成愈伤组织的能力上有较大的差异,秋播材料形成愈伤组织的能力明显高于春播材料。F_(?)杂种植株诱导愈伤组织和分化植株的频率均比F_1杂种明显提高。  相似文献   
3.
B. Kehrel  R. Wiermann 《Planta》1985,163(2):183-190
Phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) from anthers of the garden tulip Apeldoorn have been purified to apparent homogeneity as revealed by sodium dodecyl sulfate disc-gel electrophoresis. Phenylalanine ammonia-lyase was either purified by successive chromatography on Sephacryl S 300 Superfine, HA Ultrogel and on diethylaminoethyl Sephacel or by immunoaffinity chromatography in a single step. Purification of CHS was achieved by chromatography on Sephadex G 200 and on HA Ultrogel followed by chromatofocusing. The purified enzymes were used for the immunization of rabbits. The specificity of the antisera against both PAL and CHS was tested by diverse methods. Antisera against PAL and CHS were employed to detect the localization of the enzymes in cross sections of tulip anthers using an indirect immunofluorometric method. The results show that PAL and CHS are located predominantly in the tapetum cells. These observations strengthen the view that the tapetum plays an important role in the regulation of phenylpropanoid metabolism within the loculus of anthers.Abbreviations CHS chalcone synthase - PAL phenylalanine ammonia-lyase - SDS sodium dodecyl sulfate Some of the results were presented at the meeting of German Botanical Society in Freiburg, FRG, September 1982, and at the meeting of the Groupe Polyphenols in Toulouse, France, September/October 1982  相似文献   
4.
Summary Sixty single seed descent (SSD) lines and about 25 anther-derived doubled-haploid (DH) lines were obtained from two triticale crosses. The frequency distributions of 10 quantitative agronomic traits were compared using parametric and non-parametric tests. A multivariate discriminant analysis was subsequently carried out. Gliadin patterns obtained from each line by polyacrylamide gel electrophoresis were used to calculate intra- and inter-population diversities from relative dissimilarity indices. It was found that DH and SSD lines show significant differences in frequency distributions of 1000 grain weight in both crosses, of heading date for one cross, and of lodging susceptibility for the other cross. The results of intra- and inter-population gliadin diversity indicate that although the SSD method theoretically provides more opportunity for recombination to occur than the DH method, it did not produce a greater range of recombinants. Since there is no significant difference between SSD- and DH-line distributions for grain yield, anther culture appears to be an efficient method for producing high yielding homozygous lines from F1 hybrids of triticale in a relatively short time.  相似文献   
5.
Measurements of anther (length, width, depth), pollen grain (percent fertility, polar diameter, equatorial diameter, polar diameter/equatorial diameter ratio, volume) and pistil (stigma length, style length, ovary length, total pistil length, stigma width, style width, ovary width) were taken on 12 diverse sesame (Sesamum indicum L.) genotypes on each of four collection dates in 1994. Highly significant differences among genotype means were obtained for all characters except polar diameter. Highly significant differences among environment (collection date) means were found for ten of the 15 characters measured. Highly significant genotype x environment interactions were obtained for all characters except anther length. For the anther characters measured, relatively high repeatability values were found, ranging from 99.8% for length to 87.6% for depth. For the pollen grain characters measured, the repeatability values ranged from 67.6% for percent fertility to 23.1% for polar diameter. For the pistil characters measured, the repeatability values ranged from 94.0% for style width to 49.6% for total pistil length. These results indicate that genotype and environment influence anther, pollen grain and pistil characters. Variation in some of these morphological aspects could influence the consistency and interpretation of male transmission studies on both the applied and evolutionary levels.  相似文献   
6.
A chalcone synthase-like cDNA from rice anther   总被引:3,自引:0,他引:3  
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7.
低温预处理过程中大麦花药内源激素的变化   总被引:9,自引:0,他引:9  
徐武  李鸣 《遗传学报》1997,24(2):165-169
很多文章曾报道低温预处理可以明显提高大麦花药反应频率。但对于低温预处理的机理,至今研究报道甚少。我们应用ELISA方法测定了大麦花药低温预处理过程中内源激素IAA、iPA和ABA含量。根据实验结果,推测低温预处理改变了花药内源IAA和iPA含量,阻断了花粉原来的发育方向,使其由配子体的发育途径转向孢子体的发育途径。  相似文献   
8.
含单核中后期至后期花粉的蚕豆离体花药,经过2mM丁酸钠24小时预处理后,再漂浮培养于pH5.8或7.0的液体培养基。以不经预处理的作为对照。结果如下: 1.培养后9天内,丁酸钠预处理和培养基pH值并不明显影响花粉退化百分率。2.培养初期,pH7.0显著促进小孢子不等分裂。3.丁酸钠预处理抑制培养初期的小孢子有丝分裂,而后又显著增加小孢子均等分裂百分率。4.丁酸钠预处理导致小孢子有丝分裂类型的趋向改变。本文还对丁酸钠导致有丝分裂类型趋向改变的可能原因,进行了讨论。  相似文献   
9.
The effects of the genotype and growth medium composition on callus induction and shoot regeneration from tomato (Lycopersicon esculentum Mill) anthers were studied. Five male sterile varieties, homozygous for the recessive gene ms 1035, their isogenic fertile counterparts, and nineteen sterile mutants from an F2 population segregating for ms 1035, were tested. Callus induction and shoot formation were found to be affected by the genotype. The presence of the mutant gene ms 1035 greatly increased callus induction. A significant interaction concerning callus induction was found between the ms 1035 gene and the general genetic background. In most of the plants shoot regeneration from the anthers was associated with various degrees of callus production. However, there was no correlation between callus production and the ability to regenerate plants from that callus. Anthers isolated from plants which were heterozygous for the recessive leaf marker trifoliate, regenerated diploid plants with trifoliate leaves. The plants retained the trifoliate phenotype for over six months in culture under non-aseptic condition. Since the trifoliate phenotype appears only in the homozygous recessive state, the evidence that these trifoliate plants are doubled haploids of sporogenic origin is discussed.  相似文献   
10.
M. Horner  R. L. Mott 《Planta》1979,147(2):156-158
The numbers of embryogenic (S) grains present in in-situ mature anthers of Nicotiana tabacum L. were compared to the numbers of embryos and plantlets produced in cultured anthers excised at the optimal mitotic stage of development for anther culture. The Feulgen technique of staining embryos caused a considerable loss of grains from cultured anthers but this did not seriously affect the determination of the percentage of embryos present. In no instance did the numbers of embryos produced exceed the maximum number of S grains found, and the distributions of S grain and embryo frequencies in anthers were similar. In rare instances S grains which had undergone the first embryogenic division were observed in situ. The results indicate that all grains capable of embryogenesis are determined during early flower formation and that their number is not increased by in vitro culture.  相似文献   
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