植物组织培养中的玻璃化现象及其预防

玻璃化是植物组织培养中常见的一种现象。本从形态解剖和生理生化方面比较了玻璃化苗和正常植株的差异。围绕水势平衡、激素平衡和矿质元素平衡探讨了玻璃化发生的内在机制,在此基础上总结了防止玻璃化发生的可能途径：改善光照,选用透气封口膜,降低细胞分裂素的浓度等,并提出多学科的合作将是防止玻璃化发生的必由之路。     

芦荟组织培养研究进展(综述)

从外植体和培养基的选择、植物生长调节剂和添加物的使用、组培条件、褐化和玻璃化的控制等方面,综述近几年芦荟组织培养研究的进展,并对今后工作提出建议。     

AgNO3逆转的黄芩组培玻璃化苗的活性成分含量及其生物活性研究

研究AgNO3对黄芩组培玻璃化苗的逆转作用,并在此基础上对逆转的黄芩组培玻璃化苗的活性成分含量及活性进行分析。结果表明,AgNO3对黄芩的玻璃化苗具有明显的逆转作用,且这种逆转作用受AgNO3浓度的影响。在AgNO3的浓度为4 mg·L^-1时,玻璃化苗的逆转率最高为88%,且逆转的黄芩苗的生长状态最好。在此基础上,对逆转1个月的黄芩玻璃化苗的活性成分含量及生物活性进行研究。逆转的黄芩玻璃化苗体内黄芩苷的含量为68.6 mg·g^-1,明显高于玻璃化苗(38.3 mg·g^-1),但低于正常的组培苗(108.2 mg·g^-1)。此外,提取物的抗氧化、抗菌和抗肿瘤实验结果显示,逆转的黄芩玻璃化组培苗明显好于玻璃化苗,但仍低于正常的组培苗。以上研究结果表明,AgNO3对黄芩组培玻璃化苗具有较好的逆转及恢复作用。     

薯蓣植物组织培养的研究进展

该文综述了组织培养在薯蓣植物快速繁殖、诱导多倍体及高产无性系筛选等方面的研究状况。褐化是薯蓣植物组培中常见的一种现象,也是阻碍组培发展的一大因素,为此,该文对褐化的原理作了分析并提出了几点解决方法,旨在使组织培养在薯蓣植物上得到更广阔的应用。     

经济植物的组织培养现状及新技术的应用

植物的组织培养指将植物的离体组织或器官在适当的条件下诱导使其长成完整植株的技术。本文综述了植物组织培养技术的原理、发展情况,在具体生产实践中的运用及存在的问题。同时,为了克服传统组培方法的缺陷,诞生了各种新型的组培技术,本文介绍了开放式组培技术、光自养微繁技术等新技术的运用及发展,并对展望了我国经济植物的组织培养,以期为植物的组织培养研究提供参考。     

试管植物的玻璃化现象

试管植物的玻璃化现象是植物组织培养中出现的特有现象。玻璃化植株呈半透明状,其组织结构畸形发育,不能移栽成活于试管外。与正常组织相比,玻璃化组织内的叶绿素含量、蛋白质含量、一些酶的活力、乙烯合成能力等都有较大变化。苹果等植物还呈现特异的生理生化变化。本文概述了玻璃化组织与其培养环境的关系,探讨了玻璃化现象的成因及其防止方法。     

植物组织培养中畸形苗发生机理的研究进展

在植物组织培养中,植物苗在培育过程中容易受到多种因素的干扰,从而发生畸形现象。从当前植物组织培养畸形苗的发生机理来看,既有外在因素,也有内在因素,要想保证植物组织培养质量,满足植物组织培养需要,减少植物组织培养中畸形苗的发生,我们就要对畸形苗的发生机理进行深入研究,同时制定具体的应对措施,保证植物组织培养的整体效果满足实际需要,达到有效解决畸形苗问题的目的。为此,对植物组织培养中畸形苗发生机理进行深入研究是十分必要的。     

光调控在植物组织培养中的应用研究进展

光调控是植物组织培养中一种有效的环境控制技术。该文对近年来国内外有关光调控在植物组织培养中的应用,即光照强度、光周期、光质对组培植物的生长发育、光合作用、愈伤组织诱导及其增殖与分化、器官和体细胞胚发生、生理特性及次生代谢物质等方面的影响研究进展进行了综述,为植物细胞工程提供参考。     

木兰科植物组织培养技术研究进展

我国木兰科(Magnoliaceae)植物栽培历史悠久且种类丰富,具有很高的科研价值、观赏价值、生态价值与经济价值。但是,生境的破坏和自身繁殖能力的限制,使木兰科许多种的生存受到威胁。由于传统繁殖方式繁殖效率低下,而组织培养技术是推进木兰科种质资源保存及开发利用的有效途径,因此组织培养技术可以应用于濒危资源保护、育种和无性系苗木的商业化生产。木兰科植物的组织培养中无菌短枝扦插途径研究较多,体系已相对完善,一些种类的木兰科植物可以通过此途径得到生根苗; 而关于器官发生途径的研究相对较少,愈伤组织诱导困难及不定芽分化困难的问题仍没有得到有效解决,并且体细胞胚发生途径在国内鲜有研究。该文从无菌短枝扦插、器官发生、体细胞胚发生等不同再生途径出发,分析了外植体类型、培养基类型、生长调节剂浓度、培养条件等方面对离体生长的影响,归纳了组培过程中生根困难与褐化等技术问题与解决措施,展望了木兰科植物组织培养技术未来的研究方向,以期为木兰科植物的组培快繁技术研究提供理论依据和技术参考。     

影响枣组培苗玻璃化的几个因素及其防治（简报)1

高温、高浓度细胞分裂素6-BA和低透气性均促进枣组培苗玻璃化现象的发生,改变以上3种因子可在一定程度上防止或减轻玻璃化的发生。     

In vitro culture: an epigenetic challenge for plants

In vitro plant cell and tissue culture techniques are the basis of many micropropagation and breeding programs for scientific research. Plant tissue culture (PTC) involves organogenesis and embryogenesis, and the outcome depends on the different conditions to which the tissue is exposed. PTC is a stressful environment—high relative humidity, low ventilation rate, high concentrations of plant growth regulators, and low light availability—for plants that need to rapidly change their molecular regulation in order to respond fast and efficiently during cell division and growth. For instance, somatic embryogenesis (SE), which plays an important role in plant multiplication, requires complex cellular, biochemical and molecular processes for embryo formation and development. New data has come out about a connection between plant morphogenesis and epigenetics. Epigenetics is a very sensitive regulatory mechanism, which in most of cases is affected by the environment. Although it is known that, under plant morphogenesis, the genome has little or no change, DNA methylation and histone modifications are very susceptible to those in vitro environmental conditions. In the present review, we highlight the most used in vitro systems such as organogenesis and SE in plants and discuss how epigenetics plays a pivotal role in the phenotype outcome. Furthermore, we discuss the big role that the small RNAs have during cell division and propagation and propose different challenges and opportunities to study epigenetics in plant cell tissue and organ cultures.     

Cytokinin as an Inducer of Vitrification in Melon

Development of vitrification has been followed in melon shoottips cultured on solid and liquid media which contained growthfactors in various concentrations. Cytokinin was found to bethe primary inducer, without which vitrification did not occurin spite of the presence in the culture of other accepted inducers.Spontaneous vitrification appeared on non-inductive media butin a low percentage. Vitrification differed in appearance andfrequency, depending on the kind of medium. On solid mediumvitrification gradually increased with time, whereas on liquidmedium it was an ‘all-or-nothing’ effect. On solidmedium, all the vitrified plantlets turned into callus aftertwo or three subcultures. It is suggested that vitrificationis the bud's reaction to an excess of cytokinin. Cucumis melo, growth factors, abnormal plant growth, vitrification     

Spatial integration of partners and heteromorphism of cyanobacterium Nostoc muscoum CALU 304 in mixed culture with Rauwolfia

A comparative morphological study was conducted of Nostoc muscorum CALU 304 grown either as a pure culture on standard media or as a mixed culture with Rauwolfia callus tissue on a medium for plant tissue cultivation. The interaction of the cyanobacterial and plant partners results in their spatial integration into aggregates of specific anatomy, which arise periodically during the mixed culture growth. The morphology of the cyanobacterial cells varies depending on their localization in the combined aggregate. The degree of cyanobacterial heteromorphism increases with time of growth of the association. Evidence of the plant origin of the factors inducing heteromorphic changes in N. muscorum was obtained, as well as evidence indicating that these factors can rapidly diffuse in agarized medium. A conclusion is inferred that the heteromorphic cells correspond to bacterial forms that appear during unbalanced growth as an adaptation to altered environmental conditions.     

Spatial integration of the partners and heteromorphism of the cyanobacteriumNostoc muscorum CALU 304 in a mixed culture with theRauwolfia tissue

A comparative morphological study was conducted ofNostoc muscorum CALU 304 grown either as a pure culture on standard media or as a mixed culture withRauwolfia callus tissue on a medium for plant tissue cultivation. The interaction of the cyanobacterial and plant partners results in their spatial integration into aggregates of specific anatomy, which arise periodically during the mixed culture growth. The morphology of the cyanobacterial cells varies depending on their localization in the mixed aggregate. The degree of cyanobacterial heteromorphism increases with the time of growth of the association. Evidence of the plant origin of the factors inducing heteromorphic changes inN. muscorum was obtained, as well as evidence indicating that these factors can rapidly diffuse in agarized medium. A conclusion is inferred that the heteromorphic cells correspond to bacterial forms that appear during unbalanced growth as an adaptation to altered environmental conditions.     

包埋玻璃化法超低温保存植物种质的研究进展

包埋玻璃化法是在玻璃化法和包埋脱水法基础上发展起来的超低温保存植物种质的新技术.它具有能同时处理大量材料,处理后恢复生长快,对材料的毒害作用较小及成芽率高等优点,已成功地用于辣根、山嵛菜等20余种植物,在植物种质资源的保存上显示出了巨大的应用潜力.本文介绍了包埋玻璃化法产生的背景及其优点,阐述了包埋玻璃化法的基本方法和预培养、包埋、脱水、化冻及恢复培养等过程,比较了该法冻存后的效果和冻存后所形成植株的遗传稳定性,同时指出了进一步研究的重点.     

肌动蛋白微丝与生长素浓度梯度分布

生长素参与植物生长发育的各个阶段,如胚胎发生、发育,营养器官发生与形态建成,极性与轴向的建立,维管组织分化,生殖器官的发育等。虽然生长素在植物的各组织器官和细胞中发挥着重要的作用,植物内源生长素的生物合成却是在特异的组织——细胞快速分裂的幼嫩组织中完成的,然后通过韧皮部或受严格控制的细胞—细胞运输系统运送至植物各个部分。生长素的极性运输导致其积累在某些局部组织和细胞内,形成特定梯度分布。生长素对植物生长发育众多方面的调节正是依赖于这一特性。该文综述了近年来有关植物生长发育过程中生长素浓度梯度的形成和相应的生理功能,以及细胞骨架中的微丝参与调控生长素极性运输的研究工作。     

包埋玻璃化法超低温保存植物种质的研究进展

包埋玻璃化法是在玻璃化法和包埋脱水法基础上发展起来的超低温保存植物种质的新技术。它具有能同时处理大量材料,处理后恢复生长快,对材料的毒害作用较小及成芽率高等优点,已成功地用于辣根、山嵛菜等20余种植物,在植物种质资源的保存上显示出了巨大的应用潜力。本文介绍了包埋玻璃化法产生的背景及其优点, 阐述了包埋玻璃化法的基本方法和预培养、包埋、脱水、化冻及恢复培养等过程,比较了该法冻存后的效果和冻存后所形成植株的遗传稳定性,同时指出了进一步研究的重点。     

植物愈伤组织培养中内外源激素效应的研究现状与展望

综述了外源激素对愈伤组织诱导、分化的影响,以及内源激素在愈伤组织培养过程中的变化规律。有关愈伤组织培养中外源激素作用的研究日趋细化,而激素变化与适宜继代周期的关系已成为研究热点。随着分子生物学与同位素标记等技术的引入,必将促进愈伤组织培养中激素相关基因调控机理的揭示,以及激素作用位点的精确定位,从而推动植物愈伤组织培养的迅猛发展。     

Effect of ovarian tissue vitrification method on mice preantral follicular development and gene expression

Vitrification is considered a viable method for cryopreservation of ovarian tissue and selection of methods that minimize follicular damage is important. The objective of the present study was to evaluate the effects of two vitrification methods on ovarian tissue morphology, preantral follicles survival rate during in vitro culture, and relative expression of genes associated with oocyte maturation and cumulus expansion. Ovaries from 12-day-old mice were vitrified in media containing ethylene glycol, dimethyl sulphoxide, and sucrose. Before plunging in liquid nitrogen, ovaries were first loaded into an acupuncture needle (needle immersion vitrification [NIV]) or placed on a cold steel surface for 10 to 20 seconds (solid surface vitrification [SSV]). The integrity of the ovarian tissue was well-preserved after vitrification and was similar controls. Follicle viability in the SSV group was lower (P < 0.05) than in the control group after 6 days of culture and the NIV group after 10 day of culture. Follicle viability after 12 day of culture was 92.8%, 82.1%, and 58.4% in control, NIV, and SSV groups, respectively. Bmp15, Gdf9, BmprII, Alk6, Alk5, Has2, and Ptgs2 gene expression patterns were similar among groups. However, the level of gene expression in the vitrification groups during Days 6 to 10 were higher compared with the control group. In conclusion, ovarian tissue morphologic integrity was well-preserved, regardless of the vitrification method. Vitrification using the needle immersion method resulted in greater follicular survival after 12 day of culture than the SSV method. Gene expression patterns during culture did not seem to explain the reduced survival rate observed in the solid surface group.