植物试管苗离体生根研究进展

综述了植物试管苗生根机理方面的基因表达和遗传转化,内源激素和酶类活性与生根的关系;培养基组成物矿物盐类、附加有机成分(维生素和氨基酸)、生长调节物质、蔗糖、琼脂、活性碳、酚类物质,及pH值,培养条件、通气、湿度、温度和光照对试管苗生根的影响;外植体基因型与插条生理和发育状态与生根的关系,为植物组织培养试管苗生根研究提供一定的参考.     

毛白杨与珠美海棠试管苗低温贮存技术初探

林木试管苗通过0～10℃的自然低温贮存后,具有较高的成活率且抗冷性明显提高。观察和分析不同贮存阶段的试管苗形态和生理指标的变化,结果表明,试管苗随着贮存温度的降低,淀粉呈下降趋势,而可溶性糖相应上升,粗蛋白含量波动起伏略有升高,这是试管苗适应低温和弱光照的生理反应。贮存165 d的分化苗和120 d的生根苗污染损失率均低于10.0%;分化苗的有效苗数显著增加,生根率在95.5%以上,生根苗的移栽成活率为93.5%～98.5%。     

苦瓜快繁技术研究

研究不同激素组合对苦瓜试管苗继代增殖、生根培养的影响。结果表明:苦瓜无菌苗顶芽或带芽茎段在附加低浓度6-BA(0.2 mg/L)的MS培养基中培养,增殖效果最好,达4.92倍;试管苗在MS+IBA 0.2 mg/L的培养基中生根效果最好,其生根量不仅多,而且比较粗壮。     

外源糖对毛白杨组培芽苗气培生根的影响

组培芽苗进行气培生根培养前经外源糖溶液处理可显著提高气培茎段生根率和根系质量。试验结果表明,外源糖溶液处理可使气培茎段总含糖量、淀粉及蛋白质含量相应增加,保证了生根过程中碳水化合物的供应和酶活性。     

外源糖对毛白杨组培芽苗气培生根的影响

组培芽苗进行气培生根培养前经外源糖溶液处理可显著提高气培茎段生根率和根系质量。试验结果表明,外源糖溶液处理可使气培茎段总含糖量,淀粉及蛋白质含量相应增加,保证了生根过程中碳水化合物的供应和酶活性。     

虎头兰组培快速繁殖技术的研究

以虎头兰杂交种“黄色热带”为材料,应用组培技术对原球茎的诱导、继代增殖和芽的分化、原球茎的切割方式、试管苗生根及移栽进行了研究,初步建立一套快繁技术体系。结果表明：以MS 6-BA0．5mg／L NAA0．2mg／L利于继代增殖,繁殖系数高达4．5,有50％原球茎直接分化成完整植株,既可保持较高的繁殖系数又可直接获得生根苗用于移栽;适宜生根的培养基为MS NAA1．0mg／L AC0．5％,生根率为95％;第一、二代继代培养添加香蕉匀浆汁天然复合物对虎头兰原球茎增殖有明显作用;采用纵切方式切割原球茎,有利于提高原球茎的增殖;活性炭对试管苗的生根有促进作用;苔藓是虎头兰移栽较好的基质,在适宜的温度和湿度条件下,试管苗移栽成活率可达95％。     

萘乙酸对鄂马铃薯8号试管苗快繁的影响

以鄂马铃薯8号脱毒试管苗为实验材料,研究不同浓度的萘乙酸(NAA,0.01,0.05,0.10,0.20,0.30mg/L)对试管苗的生根、株高、叶片数和扩繁系数等方面的影响。结果表明:在温度20～25℃,光照时间16h/d,光照强度2000～3000lx,相对湿度80%的条件下,NAA浓度为0.05mg/L时,鄂马铃薯8号试管苗的生根最多,株高和扩繁系数最高。认为"MS+白糖30g/L+琼脂5.5g/L+NAA0.05mg/L"为最佳培养基。     

四倍体刺槐离体培养及其不定根发育和叶片解剖观察

 .通过茎段离体培养建立了四倍体刺槐无性系的微体繁殖体系。结果表明:基本培养基为MS或WPM培养基。BA、NAA影响芽的增殖生长,在一定的范围内,BA对芽的增殖影响比NAA大,而NAA对芽的高生长影响比BA大,二者的比例对芽的增殖生长也有影响,芽增殖生长的最适BA和NAA组合应为BA0.5mg·L-1+NAA0.1mg·L-1。四倍体刺槐无性系生根的最适生长调节物质配比为NAA0.25mg·L-1+IBA0.4mg·L-1。对试管苗不定根发育过程及分步炼苗叶片结构的变化进行了解剖观察,发现试管苗嫩梢无潜伏根原基,不定根由诱生根原基发育形成,诱生根原基源于髓射线细胞的分裂和分化,植株叶解剖观察,进一步证明了分步炼苗可提高移栽成活率。     

无病毒苹果苗试管微繁技术研究

对经脱毒的优良苹果品种北海道９号、皇家嘎拉和长富２号进行了试管微繁技术的研究。结果表明：适合于３个品种试管苗增殖的培养基为ＭＳ＋６—ＢＡ０．５ｍｇ／Ｌ＋ＮＡＡ０．０５ｍｇ／Ｌ＋蔗糖３０ｇ／Ｌ,增殖率为２５～３,≥３ｃｍ的试管苗率约为５０％。通用的生根培养基为１／２ＭＳ＋ＩＡＡ０．５ｍｇ／Ｌ＋ＩＢＡ０．５ｍｇ／Ｌ＋ＮＡＡ０．１５ｍｇ／Ｌ＋蔗糖２５ｇ／Ｌ－肌醇,平均生根率保持在７５％左右。生根试管苗采用“一步法移栽”,平均成活率在７８％以上。     

牛角瓜的组织培养

以牛角瓜的叶片为外植体,进行牛角瓜的组织培养。结果表明,培养基MS 2,4-D 2 mg/L利于愈伤组织的诱导;培养基MS 6-BA 0.5 mg/L NAA 0.1 mg/L有利于芽的分化和增殖;生根壮苗的培养基为1/2 MS NAA 0.5 mg/L,其生根率100%;试管苗生根培养30 d后移栽,成活率可达85%以上。     

百合农杆菌介导的遗传转化受体系统的建立

以麝香百合"素雅"(white-Elegance)作为供试材料建立了百合农杆菌介导的受体系统。鳞茎片的诱导分化以MS培养基中添加0.5mg/L6-BA 0.2mg/LNAA为最好;再生苗鳞茎片的不定芽分化以MS培养基中添加1.0mg/L6-BA 0.2mg/LNAA为最好;再生苗小叶柄的诱导以MS培养基中添加1mg/LNAA为佳。确定了再生苗不同部位适宜的抗生素筛选浓度,卡那霉素的筛选浓度小鳞茎块确定为125mg/L,而小叶柄确定为75mg/L;头孢霉素抑菌浓度确定为250mg/L。     

Effect of Iron and Auxins on Peroxidase Activity and Rooting Performance of Three Citrus Rootstocks In Vitro

Abstract

The effects of FeCl₃, Fe‐EDDHA and Fe‐EDTA as iron sources at 5.6 ppm, as well as their combined effect with the auxins IBA and α‐NAA on rooting capacity and total peroxidase activity of three Citrus rootstocks (Swingle Citrumelo, C. taiwanica, and C. aurantium) in vitro were studied for eight weeks. No root or callus formation was observed in the presence of IBA independently of the Fe source, or in the absence of Fe in the culture medium independently of the hormone used. Low rooting percentage obtained by FeCl₃, while the best results were obtained using Fe‐EDDHA as Fe source. The time of root appearance was also influenced by the different sources of Fe as well as by the kind of the rootstock. In the presence of Fe‐EDTA plantlets survived for four weeks and then died. Total peroxidase activity declined sharply shortly before root appearance, but the decline was less pronounced shortly before callus formation (in some cases of FeCl₃ treatment).     

基于C8051F005的组培CO2微环境调控系统的研制与试验

基于C8051F005芯片设计开发一种新型组培气体微环境控制系统，采用高纯度CO₂定压定量供给和自动箱内循环在线监测技术，成功解决了CO₂气体难以自动精确施放和传感器检测精度及其稳定性的问题，实现了组培微环境CO₂浓度的按需设定和自动控制。该系统能够同时记录CO₂浓度的下降量和时长，既可用于研究不同组培微环境因子对组培苗同化CO₂速率的影响，又能用于规模化组培育苗生产。以驱蚊香草、冬青、大花蕙兰组培苗为实验材料，验证系统可靠性与可行性。结果表明该系统运行可靠，控制精度高，能够满足规模化组培育苗对气体微环境调控的需求和组培微环境建模的科研要求。     

超声波处理对文心兰类原球茎增殖及分化的影响

采用不同频率不同时间超声波处理文心兰类原球茎（OLBs）和无菌苗，以探讨适宜的类原球茎增殖、分化及生根条件，结果表明：25kHz超声波处理组PLBs平均增殖率比40kHz超声波处理组高23．4％，其中25kHz超声波处理3min促进PLBs增殖效果较佳，PLBs平均增殖率比对照高49．5％；25kHz超声波处理组PLBs平均分化芽数比40kHz超声波处理组高28．3％，其中25kHz超声波处理6min促进分化效果较佳，平均分化芽数比对照高98．8％，25kHz超声波处理组无菌苗平均根长与平均根数比40kHz处理组高10．1％和13．6％，其中25kHz超声波处理3min促进生根效果较佳，无菌苗平均根长与平均根数比对照组高75．0％和37．5％。     

Iron‐reducing root exudates: A modified microanalytical method

Interferences were detected in the PDTS method for the measurement of Fe‐reducing compounds exuded by plant roots into Hoagland nutrient solution. These were caused by a) excess NH₃ which is present in the ammonium acetate buffer used in the assay, which forms precipitates with the KH₂PO₄ especially when nutrient solution aliquots of larger than 2 mL are to be tested, and b) the overriding effect of autoreduction of Fe due to the very high concentration of FeCl₃ present in the assay medium. A modified method is presented whereby up to 20 mL of rooting solution can be tested and the interference due to autoreduction eliminated. Comparative measurements by the proposed and the original method show that the original method overestimates the amount of Fe‐reducing root exudates by Fe‐deficient plants by more than tenfold.     

Enhanced calcium uptake in micropropagated potato plantlets by macroelement dilution

Ca deficiency disorders are common in micropropagated plantlets but little is known regarding the uptake of Ca in vitro. Ca uptake by in vitra-grown potato (Solanum tuberosum L. cvs. Bintje and Norland) plantlets was investigated when Ca levels were maintained but the total macroelement salts or just NH₄, the major competing cation, were reduced in Murashige and Skoog (MS) medium. This increased the ratio of Ca:cations or Ca:NH₄ as well as the osmotic potential of the medium. The increased Ca-cations improved Ca uptake of shoot tips, leaves, and stems while increased Ca:NH₄ had no effect. MS medium macroelement dilution may improve Ca uptake by micropropagated plantlets and prevent Ca deficiency disorders.     

四倍体刺槐无性系组织培养技术的研究

通过茎段离体培养建立了四倍体刺槐无性系的微体繁殖体系。结果表明 :基本培养基为MS或WPM培养基。BA、NAA影响芽的增殖生长 ,在一定的范围内 ,BA对芽的增殖影响比NAA大 ,而NAA对芽高的影响比BA大 ,二者的比例对芽的增殖生长也有影响 ,芽增殖生长的最适BA和NAA组合应为BA0 5mg/L +NAA0 1mg L。四倍体刺槐无性系生根的最适生长调节物质配比为NAA0 2 5mg L +IBA0 4mg L。通过植株叶解剖观察 ,进一步证明了分步练苗能提高移栽成活率。     

THE VOLUME AND POROSITY OF SOIL CRUMBS

A simple and inexpensive apparatus (a test-tube, burette, and pin) is described for measuring volumes by liquid displacement to an accuracy of greater than 0.5 per cent. This has been adapted to measure soil crumb porosities, ε_c, by saturating 3–4 g samples of crumbs with kerosene, measuring the weight of kerosene retained internally, then measuring their volume by displacement. Three estimates of crumb porosity from these measurements are compared. Experimental values range from ε_c= 0.205 for the headland of an arable field to ε_c= 0.351 for a permanent pasture. Crumb porosity is proposed as a measure of structural status for soils because it assesses the degree to which soil management has succeeded in holding the constituent primary particles apart from the positions of inherent closest packing that they would ultimately assume in an unstable soil. By comparison, the inter-crumb porosity, ε_v, can be used as a measure of cultivation status. In the form expressed, these two porosities are related to the more frequently encountered total porosity ε_t by the relation      

阔叶猕猴桃抗生素敏感性及遗传转化的研究

以阔叶猕猴桃(Actinidia latifolia)叶片为外植体,研究了各种抗生素对形态分化和器官形成的影响,并以叶盘为受体,通过根癌农杆菌介导法获得了抗性愈伤组织和抗性芽,组织化学染色表明gus基因已在植物组织中表达。研究结果表明,对不定芽分化来说,头孢霉素(Cef)效果明显好于羧苄青霉素(Carb)。Cef浓度为300mg.L-1时效果最好,再生频率达100%,平均再生芽数达最大为9.76个芽/外植体。生根过程中高浓度的Cef(≥200mg.L-1)明显抑制生根,而Carb对生根没有显著影响。在卡那霉素(Kan)和Carb组合处理中,Carb对生根没有显著影响,但Kan明显抑制生根。随着Kan浓度的升高,生根率和平均根数迅速减少,当浓度升高到50mg.L-1时,生根完全被抑制。因此,农杆菌介导的阔叶猕猴桃遗传转化中愈伤组织和不定芽诱导过程宜选用300mg.L-1Cef来抑制农杆菌生长,Kan筛选的临界浓度为20mg.L-1。在抗性芽生根过程中Kan浓度应该控制在50mg.L-1以内,并改用Carb作为杀菌剂,生根效果会更好。该研究确定了农杆菌介导的阔叶猕猴桃叶片遗传转化中使用抗生素的种类和用量,为通过基因工程对阔叶猕猴桃进行遗传改良奠定了基础。