共查询到19条相似文献，搜索用时 593 毫秒
1.
2.
3.
针叶树体细胞胚胎发生研究进展 总被引：2，自引：0，他引：2
针叶树的体细胞胚胎发生是体细胞在人工无菌培养条件下分化产生体细胞胚胎的过程,体细胞胚胎发生途径是细胞全能性表达的一种方式,重演了合子胚形态发生的过程。自1985年Hakman等首次报道挪威云杉的未成熟合子胚形成体细胞胚并再生植株以来,针叶树体细胞胚的诱导、成熟和植株再生过程的研究取得了巨大进展。综述了针叶树体细胞胚胎发生研究领域的研究进展,总结了影响体细胞胚胎发生的主要因素,展望了这方面的研究在实际生产中的应用前景及发展趋势,并指出了该研究领域中需要解决的主要问题及解决途径。 相似文献
4.
5.
6.
林木体细胞胚胎发生的研究进展 总被引：2，自引：0，他引：2
本文概述了近年国内外林木体细胞胚胎发生研究的进展,针对存在的问题提出相应的对策,以期推动我国林木体细胞胚胎发生研究在理论上的深入和生产上的进一步应用。今后在林木体细胞胚胎发生研究方面应加强以下五方面工作:1)珍稀优异种质规模化体细胞胚胎发生植株再生体系的研究和应用;2)林木成年优树的复壮及体细胞胚胎发生植株再生系统建立;3)进一步加强体细胞胚胎发生机理和应用技术研究;4)进一步扩大林木体细胞胚胎发生再生植株体系建立的树种数量;5)加强体细胞胚胎发生植株再生系统在林木转基因方面的应用技术相关研究。 相似文献
7.
滇楸体胚发生及生理生化特性研究 总被引：2，自引：0，他引：2
探讨了滇楸体细胞胚胎发生和发育过程中形态学和解剖学特征及变化,对其发生和发育过程中的一些生理生化特性进行了初步研究.结果表明:(1)滇楸非胚性和胚性愈伤组织在细胞形态和组织结构上差异明显,滇楸体胚起源于单个胚性细胞,经历了单细胞、多细胞、球形胚、心形胚、鱼雷胚和子叶胚各阶段.(2)在胚性愈伤组织和体细胞胚胎诱导形成及发育早期,3种抗氧化酶(SOD、POD和CAT)活性均提高,而在后期体胚成熟和萌发的过程中3种抗氧化酶的活性变化趋势差异明显.(3)碳、氮类营养物质在胚性愈伤组织内大量积累,为体细胞胚胎发生奠定能量和物质基础;在体胚发育的不同阶段,碳、氮代谢呈现明显的差异. 相似文献
8.
尾叶桉胚状体植株诱导与增殖研究 总被引：6，自引：1，他引：6
本文报导了用尾叶桉种子下胚胎诱导体细胞胚胎发生，获得根苗齐全的胚状体再生植株，经过５～６代增殖培养，获得大量丛生苗，已完成移栽，炼苗的全套生产技术流程，是迄今世界松树组培由下胚轴产生胚状体小苗成功的第三例，在木本植物的同类组培成功研究中也是数例之一，在科学和林木良种快速选育与繁殖上有重要价值。 相似文献
9.
10.
杂交鹅掌楸体细胞胚胎发生研究 总被引：33，自引：1，他引：33
以杂交鹅掌楸幼胚为外植体,进行体细胞胚胎发生研究.比较了亲本基因型、发育阶段、培养条件、生长调节物质和渗透压等对体细胞胚胎发生的影响.结果表明在以1/2MS培养基为基本成分,添加2.0～3.0mg@L-12,4-D的培养基上能够成功诱导胚性愈伤组织.以蔗糖为渗透剂,提高渗透压有利于体细胞胚胎发生;以MS为基本培养基附加ZT 1.0～4.0mg@L-1对体细胞胚胎诱导最有效;ABA的使用能有效控制畸形胚的产生;基因型、幼胚发育阶段及光照条件对体胚发生起着重要作用. 相似文献
11.
12.
13.
This review on current biotechnological methods in forestry for in vitro tissue cultures to define the effect of stress conditions on trees,concentrates on somatic embryogenesis.Callus tissue,the key product of somatic embryogenesis,grows over a tree wound under ex vitro conditions.Callus tissue can be used in research in areas such as pathogenic susceptibility at the embryonic level,effect of heavy metals,influence of low temperatures(cryopreservation),production of secondary metabolites and transformation of plants.Callus of arborescent plants can be induced in vitro by fungal elicitors to produce secondary metabolites for pharmaceutical and cosmetic industries and are strongly repellant to herbivores and can thus act to protect forests.Analyses of dual cultures demonstrated that callus tissue exposed to a pathogenic fungus responds by synthesizing low-molecular-mass proteins belonging to an immune protein class.Cryopreservation of embryonic callus tissue also has broad applications,e.g.,for valuable plant genotypes in gene banks.Without strategies to protect forests against stressfactors,forest ecosystems will degrade to the detriment of all life,including humans.In vitro biotechnological research using callus tissue contributes to progress in forestry and the disciplines of ecology,physiology,phytopathology,culture and selection of plants. 相似文献
14.
Technologies in forest molecular biology and tissue culture could play an increasing role in the choice of genotypes for successful establishment of agroforestry practices. Research areas such as micropropagation, somatic embryogenesis, genetic engineering, marker-aided selection, and molecular diagnostics are merging with traditional forest biological studies to help identify and produce better-suited trees for agroforestry plantings. A combination of classical and molecular biological research could be used to improve pest and stress resistance of selected genotypes, modify structure and function, and monitor pests of trees. This merger of approaches, as well as continued technological development, could accelerate the production and selection of suitable tree genotypes for agroforestry plantings.The US Government right to retain a non-exclusive, royalty free licence in and to any copy-right is acknowledged. 相似文献
15.
16.
17.
In animals, DNA methylation is related to gene silencing during ontogenic development. Little is known about DNA methylation in plants, although occasional changes in the DNA methylation state of specific gene promoters have been reported in angiosperms during some developmental processes. We found large differences in the extent of DNA methylation between meristematic areas of juvenile and mature Pinus radiata D. Don. trees, whereas differences in the extent of DNA methylation between differentiated tissues of juvenile and mature trees were small. In meristematic areas, there was a gradual decrease in extent of DNA methylation as the degree of reinvigoration increased. The observed changes in extent of DNA methylation during aging and reinvigoration indicate that reinvigoration could be a consequence of epigenetic modifications opposite in direction to those that occur during aging. 相似文献
18.
This review seeks to examine the extreme response of isolated somatic plant cells of apical meristematic tissues of mature conifer trees towards specific stress conditions in vitro resulting in somatic embryogenesis.Signal molecules regulating embryo development have been described in angiosperms,but very little is known about somatic rejuvenation in conifers.Recent studies on cloning of mature conifers provide new perspectives on signal molecules on cellular dedifferentiation into the embryogenic pathway.Our recent studies show that signal molecules such as butenolide,calcium ions,salicylic acid,antioxidants,amino acids,triacontanol and 24-epibrassinolide all play an important role in the conversion of somatic cells into an embryogenic pathway in many recalcitrant pines.This constitutes a major breakthrough in forest biotechnology with many practical applications in clonal forestry. 相似文献