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41.
以小叶杨(Populussimoniicarr.)原生质体培养的愈伤组织为供试材料,用高压波相色谱法(HPLC),测定它们在四种不同分化培养基上四大类内源激素(IAA,GA3,CTK,ABA)的含量变化,并检定有关N的生化反应。结果表明,不同分化培养基上的愈伤组织中内源激素含量和种类差异很大。导致细胞分裂素(CTK)含量高,种类多以及细胞分裂素与生长素的比值(CTK/IAA)高的处理,有利于愈伤组织分化;但若愈伤组织中含有内源脱落酸(ABA),则抑制分化。测定结果还表明,小叶杨原生质体培养的愈伤组织分化过程中,其硝酸还原酶活力与氨基态N含量互为消长。分化频率高的愈伤组织中,硝酸还原酶活力低,而氨基态N含量高. 相似文献
43.
毛白杨纤维素合酶基因(PtoCesA1)的克隆及其在烟草中的遗传转化 总被引:1,自引:0,他引:1
克隆毛白杨纤维素合酶基因(PtoCesA1),全长为3 215 bp,与欧洲颤杨的PtrCesA1基因的同源性为97%,具有开放的阅读框,编码区在52~2 988碱基之间,为2 937 bp.构建PtoCesA1基因的全长正义植物表达载体为pBIPA1,经酶切和PCR鉴定确认载体构建正确.通过农杆菌介导的方法将pBIPA1表达载体转入烟草中,转基因植株的纤维细胞壁厚度和木质部厚度都有不同程度的下降,形态表征为植株明显变矮,叶片变小. 相似文献
44.
通过实验探讨了三倍体毛白杨低硬度NaOH-AQ浆(卡伯值13.5,粘度851mL/g。白度37%,ISO)H2O2强化氧脱木质素(QOP)的工艺务件,在此基础上提出了QOP、QP全无氯漂白的漂序,此漂序可以把该纸浆漂至82.0%(ISO),粘度保持在716mL/g,漂后纸浆得率91.78%,而且该漂序可操作性强,是一种适合低硬度NaOH-AQ浆的全无氯漂白新工艺。 相似文献
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49.
Lin Shanzhi Zhang Zhiyi Lin Yuanzhen Liu Wenfeng Guo Huan Zhang Wei Zhang Chong 《中国林学(英文版)》2004,6(3):1-8
To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), malonaldehyde (MDA), protective enzymatic systems, and some key enzymes involved in the
ascorbate- glutathione cycle were comparatively studied in both normal and vitrified shoots of P. suaveolens. The results show that the lower activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate
reductase (DHAR), glutathione reductase (GR) and PAL, and the less contents of chlorphyll, lignin, ascorbate (ASA) and reduced
glutathione (GSH) as well as the lower ratios of ASA / DHA and GSH / GSSG are observed in vitrified shoots than in normal
ones during the whole culture period. While in comparison with normal shoots, the higher activity of superoxide dismutase
(SOD) and the more concentrations of water, H2O2, MDA, dehydroascorbate (DHA) and oxidized glutathione (GSSG) are found in vitrified shoots. Statistical analysis indicates
that the enhanced activity of SOD and the decreased activities of CAT and POD as well as some enzymes involved in the ascorbate-glutathione
cycle might be closely correlated to the accumulation of H2O2. The less regeneration of ASA and GSH and the lower capacity of the ascorbate-glutathione cycle observed in vitrified shoots
might be due to a significant decrease in APX, MDAR, DHAR and GR activities and a decline in redox status of ASA and GSH.
The decreases in chlorphyll content might result in a decline in photosynthesis. The lower activities of POD and PAL could
result in the decrease of lignin synthesis and cell wall ligination, which might be the key factor leading to the increase
in water content. It is concluded that the deficiency of detoxification capacity caused by the lower capacity of the ascorbate-glutathione
pathway and the decreased activity of protective enzymatic system might lead to the large accumulation of H2O2 and the enhancement of membrane lipid peroxidation, which might be the main cause leading to the occurrence of vitrifying
shoots of P. suaveolens in tissue culture.
[Supported by National Natural Science Foundation of China (Grant No. 30271093) and the Foundation of State-designated Base
for Biology Researching and Teaching in Beijing Forestry University] 相似文献
50.
三倍体毛白杨无性系木材两个切面密度的可视化 总被引:4,自引:0,他引:4
This study uses two different mathematical models and gets two dimensional graphs of longitudinal and tangential section wood density at the same time by the radial wood density data measured by X-ray. The graph is direct and clear. It can be used to analyze the distribution and difference of wood density. It can also be done various kinds of transformation, including different angle, different colors, space and plane, part and entirety. This develops the visible analysis of wood density. Next the distribution of wood density of veneer will be simulated by new mathematical model and radial wood density data. 相似文献