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81.
4种红豆杉属植物遗传多样性和遗传关系的RAPD分析 总被引:1,自引:0,他引:1
采用RAPD标记研究了分属于4种红豆杉属(Taxus Linn.)植物的68个单株的遗传多样性,并采用UPGMA方法分析68个单株的遗传关系.结果表明:12条RAPD引物共扩增出109条带,其中多态性条带108条,多态性条带百分率为99.1%;平均每条引物扩增出9.1条带.南方红豆杉[T.wallichiana var.mairei (Lemée et Lévl)L.K.Fu et Nan Li.]种内的多态性条带百分率和观察等位基因数均最高;欧洲红豆杉(T.baccata Linn.)种内的有效等位基因数、Nei's基因多样度和Shannon's信息指数均最高;须弥红豆杉(T.wallichiana Zucc.)种内的各项遗传多样性指数均最低.供试4种植物的种内遗传多样度、种间遗传多样度、基因流和种间遗传分化系数分别为0.1745、0.358 6、0.401 7和0.554 5,表明55.45%的遗传变异发生在种间.南方红豆杉和须弥红豆杉遗传距离最近;曼地亚红豆杉(Taxus×media Rehd.)和须弥红豆杉的遗传距离最远.通过聚类分析可将68个单株分为3组,欧洲红豆杉的18个单株和曼地亚红豆杉的18个单株分别各自聚为1组;须弥红豆杉的16个单株和南方红豆杉的16个单株聚为1组,其中须弥红豆杉的16个单株和南方红豆杉的16个单株又各自聚为1个亚组,且南方红豆杉的雌、雄单株也分别聚在同一分支上,表明须弥红豆杉和南方红豆杉遗传关系较近,而欧洲红豆杉与其他3种植物的遗传关系较远. 相似文献
82.
为了提高樟叶越桔(Vacciniumdunalianum)悬浮培养细胞的生物量,以樟叶越桔叶片愈伤组织为试材,通过单因素试验探究不同蔗糖浓度、培养基pH值、培养基体积、初始接种量和摇床转速对悬浮培养细胞生长的影响,并根据响应面法Box-Behnken试验设计原理进行组合试验以优化培养条件。结果显示,以改良WPM培养基为基础培养基,樟叶越桔细胞悬浮培养的最优条件为40 g·L–1蔗糖、培养基pH5.2、培养基体积45 mL、初始接种量2.64 g和摇床转速为149 r·min–1,其细胞生物量干重为0.184 4 g,与理论预测值0.184 5 g较为接近,且细胞的生长曲线呈S型。研究结果为樟叶越桔悬浮培养细胞次生代谢产物的生产调控奠定了技术基础。 相似文献
83.
以种子萌发根尖和花药愈伤组织为材料,研究了取样时间、预处理方法对百日草染色体制片的影响。结果表明:根尖上午8:00~9:00,花药愈伤继代3~5d上午9:00~10:00为最佳取样预处理时间;采用三种药剂预处理活体根尖,以4℃下饱和对二氯苯溶液或0.002mol/L的8-羟基喹啉液预处理8h效果最佳,花药愈伤则以饱和对二氯苯溶液预处理6h效果最佳。本实验的预处理温度是固定的,可克服预处理随季节和时间温度的变化而带来的不稳定性,且百日草花药愈伤染色体观察为首次报道。 相似文献
84.
Four different ratios of river sand, ceramic pellets, vermiculite and perlite (1:1), and field soil were selected as the
substrates in this experiment, and four gradient levels of root waterlogging, half waterlogging, full waterlogging
and normal were set to investigate the effects of different gradients of waterlogging stress on the root morphology
of Taxus chinensis var. mairei seedlings under different substrates. In this study, the root anatomical structure of
Taxus chinensis var. mairei under different waterlogging stress was observed by the paraffin section method. The
roots of T. chinensis var. mairei were diarch, with no pith and resin canals. There was a large number of tannins in
the pericycle of the aerial adventitious roots of seedlings adapted to waterlogging. Also, the endodermis has
obvious casparian strip thickening, and there were 4-5 layers of large parenchymatous cells in the close to the
inner side of the pericycle in the vascular cylinder, which could increase the storage capacity, and transport capacity of the root. Under the treatment of root waterlogging stress, the development of plant roots in the mixed
substrate of vermiculite and, perlite was the earliest. Under half waterlogging stress, T. chinensis var. mairei seedlings treated with various substrates all could better adapt to the environment of waterlogging stress. Under the
stress of fully waterlogging, the roots of seedlings planted in river sand substrate developed secondary growth. 相似文献
85.
86.
87.
Ying-Jin Yuan Jing-Chuan Li Zhi-Qiang Ge Jin-Chuan Wu 《Journal of Molecular Catalysis .B, Enzymatic》2002,18(4-6):251-260
Generation of reactive oxygen species (ROS) induced by Ce4+ in suspension cultures of Taxus cuspidata was investigated. The burst of superoxide anions (O2√−) occurred rapidly after the addition of Ce4+ and reached maximum at 4.3 h, while the total level of the cellular reactive oxygen species maintained unchanged. The intracellular superoxide dismutase (SOD) and catalase (CAT) were activated while the intra/extracellular peroxidases (PODs) were inhibited accompanying the O2√− burst. The pretreatment of the suspension cultures with diphenylene iodonium (DPI), a suicide inhibitor of the NADPH oxidase, blocked the O2√− burst, inhibiting the cell apoptosis and taxol production induced by Ce4+. These results show that NADPH oxidase played a key role in O2√− burst and O2√− served as a mediator of Ce4+ for cell apoptosis and taxol production. The pretreatments of the suspension cultures with anthracene-9-carboxylate, an ion-channel blocker, nifedipine, a Ca2+-channel blocker, neomycin, a phospholipase C (PLC) inhibitor, or suramin, a G-protein inhibitor, decreased O2√− burst induced by Ce4+. It is thus inferred that Ce4+-induced O2√− burst, which mediated cell apoptosis and taxol production by activating the ion-channels, PLC, G-proteins and NADPH oxidase. 相似文献
88.
89.
Daxu Li Jie Zhang Jian Zhao Yi Zhang Fei Chen Jingqiu Zhu Shujun Liu Zhirong Yang 《Plant Cell, Tissue and Organ Culture》2006,84(3):285-292
The mature seeds, mesocotyls, and young leaf tips of Elymus sibiricus L. cv. ‘chuancao No. 2’ were cultured on Murashige and Skoog (MS) medium supplemented with 5.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-d) and 0.05 mg/L kinetin in the dark at 26°C, the calluses were produced. The rate of callus regeneration depended on the explants
source and plant growth regulators. Plants regenerated from whitish-yellow-coloured compact nodular callus formed after subculturing
for 8 weeks. Higher frequency (54%) of shoot differentiation was obtained from the embryo tissues of mature seed than from
either mesocotyls (24%) or young leaf tip tissues (6%) when these calluses from different types of explants were cultured
on plant regeneration medium containing half strength MS salts supplemented with 0.1 mg/L kinetin, 1.5 mg/L 2,4-D and 20 g/L sucrose. The green plants were rooted within 6 weeks in the root regeneration medium, and over 97% of these soil-established
plants were obtained in the greenhouse when potted in a sand and peat mixture medium. 相似文献