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101.
Takayuki Ishikawa Tomoko Takayama Hiroshi Ishizaka Keiko Ishikawa Masahiro Mii 《Euphytica》2001,118(1):19-27
Interspecific hybrids were efficiently produced in the cross-incompatible combination between Alstroemeria pelegrina L. var. rosea and A. magenta Bayer by culturing immature ovules with placenta 7–14 days after pollination on 2 g/l Gelrite-solidified MS medium containing
3% (w/v)sucrose. The plants showed intermediate characteristics between the parents and their hybridity was confirmed by karyotype
and DNA analyses. The mean number of chromosome association per PMC at metaphase I was 2.60I+6.70II, pollen stainability was20.8%,
and they produced viable seeds after self-pollination. Furthermore, mature plants were obtained when the hybrids were backcrossed
as male parents with both the parents. The backcross-progeny from A. pelegrina var. rosea × hybrids exhibited 3.8 to 79.7% pollen stainability and that from A. magenta × hybrids 78.8 to 98.3%. Almost all of these plants produced viable seeds after self-pollination, which implies that they
can beutilized for breeding of novel cultivars of Alstroemeria.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
102.
103.
世界极度濒危物种崖柏研究进展 总被引:2,自引:0,他引:2
崖柏(Thuja sutchuenensis)为柏科(Cupressaceae)崖柏属常绿乔木, 属我国特有、世界极危物种(CR), 具有重要的学术研究价值和广阔的开发利用前景。1892年4月在重庆市城口县首次发现, 此后"绝迹"了100多年。世界自然保护联盟(IUCN)曾将其定为野外已灭绝物种。1999年10月重新发现。在崖柏"绝迹"期间, 由于研究材料缺乏, 对崖柏的研究几近空白; 重新发现之后, 有关研究才相继展开。近十几年来, 广大科研工作者围绕崖柏的生物学特性、地理分布、群落组成与结构、种群结构与动态、遗传多样性、生态适应性、苗木繁育等开展了广泛研究, 并取得了丰硕成果。文中综述了崖柏的研究现状, 并探讨了未来的研究方向, 以期为崖柏的深入研究和拯救繁育提供参考。 相似文献
104.
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107.
以美国红枫为母本,我国原产的元宝枫为父本,采用直接授粉法、切除柱头法、切除柱头加化学试剂法3种方法在温室条件下,用超低温保存的元宝枫花粉对带有花芽的离体美国红枫枝条进行授粉实验;子房发育约20~25d之后,分别采集经不同处理的子房对其进行表面灭菌处理后,接种于1/2MS+6-BA(0.01mg/L)+NAA(0.1mg/L)的培养基上进行胚抢救培养。结果表明:含水量为12.2%的花粉经超低温保存一年之后,保持着与新鲜花粉相当的活力。3种不同的授粉方法中,生长情况最好的为直接授粉法,切除柱头加化学试剂法次之,而切除柱头发效果最差。通过胚抢救技术获得了一定量的杂种后代株系。 相似文献
108.
109.
K. Horsman T. Gavrilenko M. Bergervoet D.-J. Huigen A. T. W. Joe E. Jacobsen 《Plant Breeding》2001,120(3):201-207
Fusion experiments were performed with a first (BC1‐6738) and a second (BC2‐9017) generation backcross hybrid of 6x Solarium nigrum (+) 2x potato somatic hybrids with potato cultivars. Because no progeny was obtained from the BC2 genotypes, alternative approaches were sought to overcome the sexual crossing barrier. Five potato genotypes, one of which contains the hygromycin resistance gene, were used in the fusion experiments. All vigorous regenerants were used for the estimation of nuclear DNA content using flow cytometry. Plants with a DNA content higher than that of the BC1‐6738 or BC2 genotypes were considered potential somatic hybrids. Forty‐nine potential somatic hybrids resulted from fusion experiments with BC1‐6738, from which 20 grew vigorously in the greenhouse and flowered. After pollination with several 4x potato cultivars, eight genotypes produced seeded berries and five genotypes gave seedless berries. In addition, 11 of these 13 somatic hybrids were selected for genomic in situ hybridization (GISH) analysis to determine their genomic composition. Nine had exactly or approximately the expected number of 36 S. nigrum and 60 potato chromosomes. In one genotype, only 22 instead of 36 S. nigrum chromosomes were found and one potato chromosome was possibly missing. Only five potential somatic hybrids were detected among the 79 regenerants from BC2‐9017 (+) 2x potato fusion experiments that were analysed by flow cytometry. Two of these hybrids were rather vigorous and did flower, but pollinations with potato have not yet set any berries. 相似文献
110.
W. Horn 《Plant Breeding》1994,113(1):3-17
Different Pelargonium hybrids are of great importance to horticulture. Breeding; for F1 hybrid and clonal eultivars is particularly prevalent in Europe, Japan and North America. The results of a great deal of breeding research are scattered throughout different journals and published in several different languages. The aim of this review is to summarize the results of research on interspecific crosses and the inheritance of flower and leaf colour, plant habit, resistance and floret type. 相似文献