蒲公英研究进展和用生物技术培育耐盐蒲公英展望

蒲公英属(Taraxacum)植物种类多,分布广,是常见的农业杂草,还是重要的中药材.目前,蒲公英作为蔬菜食用得到了人们的充分重视,并逐渐成为时尚.近年来,人们深入研究了蒲公英的化学成分和药理作用,关于蒲公英的组织培养、核型与分子水平的研究也已开展,但蒲公英的生物技术培育工作鲜有报道.在对蒲公英的开发利用和研究现状作概述的同时,结合我们的工作提出生物技术培育抗盐、耐海水蒲公英的努力方向,以期为进一步开发利用蒲公英打下基础.     

利用组织和细胞培养筛选作物耐盐突变体的研究

利用组织和细胞培养筛选作物耐盐突变体的研究王仑山王鸣刚王亚馥（兰州大学生物系,兰州７３００００）ＴＨＥＳＥＬＥＣＴＩＯＮＯＦＮａＣｌ┐ＴＯＬＥＲＡＮＴＭＵＴＡＮＴＳＢＹＴＩＳＳＵＥＡＮＤＣＥＬＬＣＵＬＴＵＲＥＩＮＰＬＡＮＴＷａｎｇＬｕｎ－ｓｈａｎＷ...     

蒲公英耐盐突变体‘滨蒲1号'的耐盐性研究

土壤盐渍化是当今农业生产上的重要危害之一,它严重影响当地农作物的生长、发育及产量的提高。为了提高盐碱地的利用效率,该文以蒲公英耐盐突变体‘滨蒲1号’及其亲本叶片为材料进行丙二醛(MDA)含量等8种生理指标的测定,同时利用cDNA-RAPD技术对蒲公英耐盐突变体及其亲本根胁迫0、12、24 h的差异表达基因进行分析。结果表明:(1)突变体‘滨蒲1号’叶片中脯氨酸含量、叶绿素含量、可溶性蛋白含量、CAT活性、POD活性、SOD活性在不同胁迫时间点均大体高于亲本; MDA含量、相对电导率低于亲本。(2)以筛选出的10条RAPD引物进行cDNA-RAPD分析,共扩增出22条清晰的条带,差异条带10条,多态性为45.4%。(3)扩增产物片段大小在150～1 000 bp之间,主要为盐抑制基因片段,推测蒲公英耐盐突变体‘滨蒲1号’的耐盐性既与渗透调节物质脯氨酸及多种抗氧化酶上升引起的保护作用有关,也与根中一些与耐盐相关的基因表达变化有关。该研究为进一步克隆蒲公英耐盐基因并利用基因工程手段培育耐盐优质的蒲公英新品系奠定一定的理论基础。     

利用组织培养研究植物耐盐机理与筛选耐盐突变体的进展

概要介绍近年来利用组织培养研究植物耐盐的机理,培养的细胞与整株植物之间耐盐的相关性,列举国内外从17种植物筛选出的耐盐细胞系及其再生植株的研究结果,讨论了选择细胞的耐盐性在再生植株表达的问题,并展望这项研究工作的前景。     

海水组培法培育芦荟耐盐品系研究

以库拉索芦荟(Aloe vera)组培苗为材料,在培养基中添加不同浓度海水对芦荟进行盐胁迫驯化培养.结果显示:(1)在50%海水处理的组培植株性状分离最明显,且有部分芦荟苗生长旺盛;盐胁迫驯化前芦荟(库拉索)与盐胁迫驯化后芦荟('南盐1号')的组培苗在分化过程中存在明显的差异,库拉索芦荟的芽分化率、平均分芽数、心叶生长速率及生根系数等指标均明显低于同比例海水处理下的'南盐1号';'南盐1号'芦荟苗在0～20%海水条件下组培时,芦荟分化率随着海水浓度的加大而降低,而30%海水组培处理时芦荟芽增长数上升至淡水组培水平,且平均心叶数增加速率最大,根生长变化特征与其芽分化生长基本一致.(2)移栽入圃后用50%天然海水灌溉时,'南盐1号'芦荟植株根系发达,生长正常,而库拉索芦荟则盐胁迫症状明显;经一年大田海水灌溉比较试验发现,'南盐1号'的地上部与根部的鲜重在淡水灌溉下与库拉索芦荟没有差异,而在30%和60%比例的海水灌溉下均显著高于库拉索芦荟;用30%的海水灌溉培养下,'南盐1号'地上部产量与淡水灌溉的产量无显著差异,而库拉索芦荟的地上部产量却比淡水处理降低15%～20%.研究表明,通过海水组织培养能筛选出芦荟耐盐株系,且其耐盐分化株系筛选的最适浓度为50%海水.     

杜氏盐藻的耐盐机制研究进展和基因工程研究的展望

概述了杜氏盐藻（Dunaliella salina）的耐盐机制和基因工程的研究进展。盐藻的耐盐机制十分复杂,短时间内通过细胞体积的改变来调节渗透压平衡,之后通过甘油的合成与转化恢复细胞正常形态和大小。渗透调节过程中,还涉及到蛋白质的合成。cDNA文库和基因组文库已经建立;几种基因已被克隆,如碳酸酐酶基因和硝酸还原酶基因等;GUS（β_葡糖苷酸酶）基因已成功地转入盐藻细胞内。另外,对盐藻的基因工程作了简单的展望。     

杜氏盐藻的耐盐机制研究进展和基因工程研究的展望

概述了杜氏盐藻 (Dunaliellasalina)的耐盐机制和基因工程的研究进展。盐藻的耐盐机制十分复杂 ,短时间内通过细胞体积的改变来调节渗透压平衡 ,之后通过甘油的合成与转化恢复细胞正常形态和大小。渗透调节过程中 ,还涉及到蛋白质的合成。cDNA文库和基因组文库已经建立 ;几种基因已被克隆 ,如碳酸酐酶基因和硝酸还原酶基因等 ;GUS(β_葡糖苷酸酶 )基因已成功地转入盐藻细胞内。另外 ,对盐藻的基因工程作了简单的展望     

植物耐盐研究进展

综述了盐胁迫对植物的损伤和其中的各种生理生化过程,以及植物在抵抗盐胁迫过程中的耐盐机理。新的研究成果表明,植物自身的miRNA可能在植物抗逆境过程中起到了重要作用,甲基化过程参与了抗逆境相关的甜菜碱等小分子有机物质的合成。     

园艺植物耐盐细胞突变体的筛选和鉴定

本文介绍了园艺植物耐盐细胞突变体获得途径及其耐盐性鉴定的研究进展。     

小麦耐盐突变体的RAPD分析

以冀麦２４和其耐盐的一代８９０１－１７为材料,用ＲＡＰＤ技术对其进行比较分析研究。在的用的２１５个引物中有５１个扩增出多态性,既有量的差异又有质的差异,初步断定此５１个引物扩增出的多态性与突变有关,为进一步用ＢＳＡ方法细筛出与耐盐突变体紧密连锁的ＲＡＰＤ分子标记下打下基础,同时,还分析了影响ＲＡＰＤ扩增结果的因素。     

Biotechnological Approaches for Developing Salt Tolerant Field Crops

Plant cell cultures have been widely used to screen against salt, salt mixtures, sea water and proline analogues, to develop salt tolerant genotypes in crop species. In some cases, selected trait expressed in regenerated plants has also been shown to be inherited through the sexual cycle. Besides, salt-tolerance character available in the wild germ plasm could be introgressed into the economic target species through improved wide hybridization techniques (e.g. embryo rescue, protoplast fusion, etc.). The third approach makes use of the recombinant DNA technology for identification, cloning, transfer and expression of the salt-tolerance genes in the target species. Basic research on salt-tolerance mechanisms at molecular level, stress related proteins and DNA sequences, plant morphogenesis, somatic cell hybridization, developmental regulation and selection strategies, however, need to be intensified to accelerate breeding for this complex characteristic.     

Advances in Salt Tolerance of Some Major Fiber Crops Through Classical and Advanced Biotechnological Tools: A Review

Journal of Plant Growth Regulation - Plant biofibers are of great economic and commercial importance. Among various fiber producing crops, cotton (Gossypium hirsutum L.), hemp (Cannabis sativa L.),...     

Breeding for Salinity Tolerance in Plants

Accumulation of high levels of salts in the soil is characteristic of arid and semi-arid regions. Although different curative and management measures are being used to render salt-affected soils fit for agriculture, they are extremely expensive and do not provide permanent solutions to overcome the salinity problem. In contrast, a biotic approach for overcoming salinity stress has gained considerable recognition within the past few decades in view of the vast experimental evidence from what has happened in nature concerning the evolution of highly salt-tolerant ecotypes of different plant species, and also from the remarkable achievements that have been made in improveing different agronomic traits through artificial selection.

Considerable improvements in salt tolerance of important crop species have been achieved in the past 2 decades using barley, rice, pearl millet, maize, sorghum, alfalfa, and many grass species. Such achievements relied solely on assessment of the phenotypic expression of the features involved. Knowledge of the underlying physiological mechanisms producing those salt-tolerant individuals was not clearly known. The present review highlights the relationships between different physiological/biochemical variables being recommended as selection criteria, and salt tolerance of different plant species. This paper also lists different sources of genetic variation for salt tolerance since it is evident that for successful improvement in a character there must be a great amount of genetic variation present in the gene pool of a species.     

小麦品种资源耐盐性鉴定

按照农业部行业标准NY/PZT001-2002,对882份小麦品种资源进行耐盐性初步鉴定,筛选出芽期耐盐性为一级的品种328份,苗期和芽期都达到中度耐盐的品种43份。这些品种中很多既具有中度或中度以上耐盐性且具有高产优质等优异特性,如小偃22、新曙光1号等,为小麦耐盐育种提供重要信息。相关分析表明,不同耐盐级别的小麦品种其芽期和苗期耐盐性并没有一致的相关关系,二者并没有可比性,在耐盐种质筛选过程中,都有其本身的意义。     

Salt Tolerance in Soybean

Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.     

Salt Tolerance in Soybean

Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.     

Salt Tolerance ofEchinochloa crusgalli

Salt tolerance ofEchinochloa crusgalli was studied using gravel culture with root medium electrical conductivity between 3 to 25 dS m^-1. Salinity depressed germination and shoot yield. A 50 % reduction in shoot yield occurred at 15.9 dS m^-1. The plant was able to maintain its tissue water content and K concentration in the tissue water while Na, Ca and Cl increased and Mg decreased with increasing root zone salinity.     

大豆耐盐机理及相关基因分子标记

大豆耐盐涉及多种生理代谢途径.耐盐大豆能够通过Cl-排除、控制Na 的吸收和转运、合成渗透调节物质、改变细胞膜膜脂组分及相关酶类的活性等多种形式来适应盐胁迫;野生大豆群体具有盐腺,从形态结构上适应盐逆境;大豆-根瘤菌共生体在盐胁迫下通过互作来提高整体的耐盐性.分子生物学技术应用于大豆耐盐研究,已获得了一些与耐盐相关基因连锁的分子标记.广泛搜集筛选大豆栽培种和野生种资源,利用分子生物学技术和基因工程提高大豆耐盐性,将成为未来大豆耐盐研究的主要内容.     

大豆耐盐机理及相关基因分子标记

大豆耐盐涉及多种生理代谢途径。耐盐大豆能够通过Cl-排除、控制Na+的吸收和转运、合成渗透调节物质、改变细胞膜膜脂组分及相关酶类的活性等多种形式来适应盐胁迫;野生大豆群体具有盐腺,从形态结构上适应盐逆境;大豆-根瘤菌共生体在盐胁迫下通过互作来提高整体的耐盐性。分子生物学技术应用于大豆耐盐研究,已获得了一些与耐盐相关基因连锁的分子标记。广泛搜集筛选大豆栽培种和野生种资源,利用分子生物学技术和基因工程提高大豆耐盐性,将成为未来大豆耐盐研究的主要内容。