芦苇细胞培养中的染色体稳定性及诱变效应

培养一年后的芦苇愈伤组织中,仍以80％的八倍体细胞占绝对优势。染色体数目变异范围在105—26之间。而EMS处理的愈伤组织与末经处理的愈伤组织相比较,明显地具有比较高的染色体数目变异和倍性变异。     

芦苇变异植株的细胞学鉴定

芦苇变异植株是从EMS处理的愈伤组织再生的。植株是混倍体·染色体数目变异范围在100—33之间。在它们的分蘖植株中,存在类似的染色体数目变异。     

芦苇变异植株的细胞学鉴定

芦苇变异植株是从 EMS 处理的愈伤组织再生的。植株是混倍体·染色体数目变异范围在100—33之间。在它们的分蘖植株中,存在类似的染色体数目变异。     

芦苇耐盐变异植株及其细胞学鉴定

用甲基磺酸乙酯（ＥＭＳ）处理芦苇（Ｐｈｒａｇｍ ｉｔｅｓｃｏｍ ｍ ｕｎｉｓ Ｔｒｉｎ．）胚性愈伤组织。从处理后的愈伤组织诱导获得芦苇耐盐变异植株Ｒ５００２－１２。变异植株能在含有１％ ＮａＣｌ的ＭＳ培养基上生长。细胞学检查变异植株是混倍体,染色体数目变异范围在１００至３３ 之间。分蘖植株具有相似的形态学及染色体变异特性     

小麦愈伤组织及再生植株的染色体变异

对培养在含有不同附加成分的MS培养基上的小麦愈伤组织染色体进行了跟踪研究。结果表明,在整个培养过程中各培养基上愈伤组织都有一定程度的染色体变异。在培养初期,高浓度2,4-D可增加愈伤组织中的染色体变异率,AgNO_3可降低染色体变异率。6-BA对培养初期愈伤组织染色体变异率没有显著影响。但高浓度6-BA可加大长期培养愈伤组织中的超倍体细胞频率。蔗糖浓度对最初9代愈伤组织染色体变异率无显著影响。但之后,低浓度蔗糖培养基上亚倍体细胞频率明显减小。随着培养时间的延长,各培养基上愈伤组织中正常二倍体细胞的频率都有逐渐上升的趋势。在再生植株中,大部分核型正常,只有少数植株具有染色体数目或结构变异。有些核型正常植株也有表型变异。     

新疆紫草的组织培养及其染色体分析

新疆紫草(Arnebia euchroma)的胚轴、子叶、根都产生愈伤组织。不同来源的外植体产生苗的能力不同,胚轴来源的愈伤组织分化苗最多,而且苗生长旺盛。根的愈伤组织只产生不定根。新疆紫草的核型是 K(2n)=14=2m 8sm 2sm(SAT) 2st。随着继代培养代数增多,染色体变异的种类和频率以及染色体数目显著增加。如果继代培养时间较长,染色体数目变异的范围更广,而且出现染色体结构变异。     

新疆紫草的组织培养及其染色体分析

新疆紫草(Arnebia euchroma)的胚轴、子叶、根都产生愈伤组织。不同来源的外植体产生苗的能力不同,胚轴来源的愈伤组织分化苗最多,而且苗生长旺盛。根的愈伤组织只产生不定根。新疆紫草的核型是K(2n)=14=2m+8sm+2sm(SAT)+2st。随着继代培养代数增 多,染色体变异的种类和频率以及染色体数目显著增加。如果继代培养时间较长,染色体数目变异的范围更广,而且出现染色体结构变异。     

球根海棠继代愈伤组织分化潜力丧失研究(简报)

球根海棠愈伤组织出芽率高，愈伤组织继代半年后分化能力丧失；降低或去除培养基中植物生长调节剂等并不能恢复；镜检愈伤组织发现细胞染色体数目已发生广泛变异。     

银鹊树胚性愈伤组织继代培养过程中的细胞染色体数目变异

以银鹊树幼嫩的合子胚为外植体诱导胚性愈伤组织,胚性愈伤经增殖后转接到液体培养基中悬浮继代培养,对其多次继代培养的胚性愈伤细胞的染色体数目检测发现:多次继代培养后的胚性愈伤细胞染色体数正常的比例为48.28%(2n=30),部分细胞出现染色体数目2n=15~60的变异,其变异率高达51.72%,其中以亚二倍体变异为主(40.07%).结果表明,在体细胞胚胎诱导形成过程中,胚性愈伤组织细胞在染色体水平上发生部分变异,这可能是体胚形成过程中畸形胚产生的根本原因.     

不同激素对伊贝母组织培养中染色体不稳定性的研究

伊贝母鳞茎培养在附加2,4—D、IAA、NAA和2,4—D+KT、IAA+KT、NAA+KT的MS培养基上(2,4—D、IAA、NAA1毫克/升,KT0.1毫克/升),研究了愈伤组织细胞染色体的变异及愈伤组织的分化和再生植株的染色体倍性。结果表明,2,4—D能有效地引起染色体数目的变化,当和KT结合使用时,可诱导高频率的多倍化细胞。IAA的作用次之,NAA较小。各种激素均能程度不同地引起各种类型的有丝分裂异常及染色体结构变异,其效应与对染色体数目变异的影响呈现明显的一致性。研究还得出,染色体的整倍性是愈伤组织得以分化的重要因素,所以再生植株主要是二倍体,也有少量的四倍体,混倍体仅占少数。根据实验结果,对染色体变异的原因以及染色体数目变异与愈伤组织分化的关系进行了讨论。     

Development of NaCl-tolerant line in Chrysanthemum morifolium Ramat. through shoot organogenesis of selected callus line

Plants were regenerated successfully through shoot organogenesis of a NaCl-selected callus line of Chrysanthemum morifolium Ramat. cv. Maghi Yellow (a salt sensitive cultivar), developed through stepwise increase in NaCl concentration (0-100mM) in the MS medium. The stepwise increase in NaCl concentration from a relatively low level to cytotoxic level was found to be a better way to isolate NaCl-tolerant callus line, since direct transfer of callus to high saline medium was detrimental to callus survival and growth. The selected callus line exhibited significant increase in superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2) activities compared to control callus (grown in medium devoid of NaCl). Stability of salt tolerance character of the selected callus line was checked by growing the calli in NaCl-free medium for 3 consecutive months followed by re-exposure to higher salinity stress (120mM NaCl). Among different growth regulator treatments, a combination of 5mgl(-1) TDZ (Thidiazuron) along with 0.25mgl(-1) NAA and 0.5mgl(-1) GA(3) was found to be the most effective for shoot organogenesis in selected callus line. The regeneration potential of the NaCl-tolerant callus ranged from 20.8% to 0% against 62.4% to 0% in control callus line. Under elevated stress condition (medium supplemented with 250mM NaCl), selected calli derived regenerants (S1 plants) exhibited significantly higher SOD and APX activities over both PC (positive control: control callus derived plants grown on MS medium devoid of NaCl) and NC (negative control: control callus derived plants subjected to 250mM NaCl stress) plants. In addition, the NC plants showed stunted growth, delayed root initiation, and had lesser number of roots as compared to S1 plants. Based on growth performance and antioxidant capacity, the S1 plants could be considered as NaCl-tolerant line showing all positive adaptive features towards the salinity stress. Further study on agronomic performance of these S1 plants under saline soil condition need to be undertaken to check the genetic stability of the induced salt-tolerance.     

Callus tissue of Solanum tuberosum L. cultured in the presence of the pyrethroid deltamethrin

The effect of Decis (deltamethrin as active ingredient) on callus tissue of Solanum tuberosum L. cv. Désirée was studied. Decis is an agrochemical currently used on field grown potato plants to control the Colorado beetle, a potato pest. Deltamethrin added to the culture medium interferes with the behaviour of callus tissue. After 5 h of culture, the level of total proteins was higher in treated tissue than in the control, and SDS-PAGE showed that deltamethrin promoted the increase of some soluble proteins. After 24 h and 14 days of culture, the level of total proteins became similar in both treated and control material. This similarity between control and treated tissues, after 14 days of culture, occurred as a result of the treatment with deltamethrin which caused a decrease of soluble proteins, but an increase in insoluble proteins whereas the opposite was observed for control callus. SDS-PAGE of both soluble and insoluble proteins showed that only quantitative dissimilarities occurred. This longer treatment also increased the chlorophyll content. Ultrastructural study of the cells revealed that tissue callus cultured for 14 days in the presence of deltamethrin had plastids containing a more developed membranous system, with a higher number of grana and with more compartments than in control cells. Deltamethrin also promoted the abundance of vesicles associated with dictyosomes. This response of the callus tissue to Decis added to the callus medium parallels the behaviour of potato plants treated with this agrochemical under field conditions (Fidalgo, Santos & Salema, 1993).     

Role of polyamines in the cytokinin-dependent physiological processes. I. Effect of benzyladenine on polyamine levels during chloroplast differentiation in the tissue culture of Dianthus caryophyllus

Tissue culture of Dianthus caryophyllus L. (cv. William Sim.) obligatory requiring N⁶-benzyladenine for greening provides a good system to study the interactions between cytokinins and polyamines. Polyamines were analyzed as dansyl derivatives which are separated by thin layer chromatography and detected by fluorescence spectrophotometry. Green callus growing on benzyladenine — containing medium showed decrease in the contents of free, conjugated and bound putrescine and spermidine in comparison to chlorophyll-less callus (control callus) growing on cytokinin-free medium. The level of spermine free, conjugated and bound forms increased about 6 %, 77 % and 28 % respectively in tissue culture growing in the presence of cytokinin. Spermidine was dominant polyamine bound to chromatin isolated from control callus. Chromatin isolated from green callus was characterized by a lower level of each polyamine in comparison to chlorophyll-less callus. Polyamines were found in plastid membrane fraction isolated from chlorophyll-less and green callus. A significant increase the levels of polyamines (putrescine, spermidine and spermine) bound to plastid membranes in green callus (+ benzyladenine) in comparison to chlorophyll-less callus (− benzyladenine) was observed. Additionaly, methylglyoxal-bis(guanylhydrazone) an inhibitor of S-adenosylmethionine decarboxylase depressed the greening process. Our results suggest that cytokinin-induced chloroplast differentiation in carnation tissue culture may be partly mediated through the polyamines bound to thylakoid membranes. A possible role of polyamines during cytokinin-induced formation of photosynthetic apparatus is discussed.     

Effects of ionizing radiation (60Co gamma rays) on growth and morphogenesis ofHaworthia mirabilis,haw. Callus tissue

Summary The effects of γ-radiation on growth and morphogenesis ofHaworthia callus in vitro were determined. The doses ranged from 100 to 5000 rads. Survival, growth pattern, growth rate, and differentiation of vegetative buds and roots in both irradiated and nonirradiated callus were compared. Growth data up to 24 weeks for irradiated and control cultures were analyzed. The dose range between 800 to 2500 rads produced compact callus as compared to the controls which were friable. After 12 weeks all control cultures differentiated vegetative buds with roots, whereas callus exposed to 800 to 2500 rads continued to grow with little or no organogenesis. However, it was observed that the wet and dry weights of callus receiving 1000 to 1500 rads ultimately exceeded those of nonirradiated controls.     

亚麻耐盐性愈伤组织的生理生化特性

以亚麻(双亚5号)耐盐愈伤组织为材,以同种亚麻普通愈伤组织为对照,分别经含0~250 mmol·L^-1 NaC1的培养基培养20 d后,比较含水量、MDA含量、POD酶活、SOD酶活、EST同工酶谱、POD同工酶谱及SOD同工酶谱。结果表明：亚麻耐盐组愈伤组织与对照组愈伤组织在多方面存在明显差异,前者含水量均高于后者;丙二醛含量也高于后者,但变化幅度不大;POD酶活均高于对照组;酯酶同工酶谱不同于对照组,酯酶酶活量均高于对照组;POD同工酶谱比对照组多一条带,且酶活均高于对照组;SOD同工酶谱与对照组一样多,但酶活均高于对照组,且平稳。这为进一步筛选亚麻耐盐突变细胞系奠定了良好的基础。     

荷兰芹胚性愈伤组织诱导及胚状体发生与内源IAA和ABA关系的初步研究

分析了荷兰芹胚性愈伤组织发生的条件, 对Co²⁺作用下胚状体形成与培养物内源IAA和ABA 的关系做了研究。结果表明, 荷兰芹下胚轴胚性发生能力随其相对位置而异, 自下而上逐渐提高。提高2, 4-D 浓度有利于胚性愈伤组织的诱导, 水解酪蛋白对胚性能力的表达没有显著影响。在胚状体发生过程中, 添加Co²⁺显著降低培养物内源IAA 和ABA 水平, 并提高胚状体诱导率。其中对照组IAA 有一个峰值, ABA 有两个峰值;实验组ABA 变化趋势与对照组相似, 而IAA 则始终没有峰值出现。Co²⁺对IAA 和ABA 的抑制机制可能有所不同。     

滇紫草愈伤组织培养与紫草素产生

浓度为10~(-5)Smol/1和10~(-6)mol/l的2,4-D和NAA分别与10~(-5)mol/l的KT组合,能明显抑制滇紫草(Onosma paniculatum Bur. et Fr.)愈伤组织中紫草素的产生,但几乎不受天然生长素IAA和KT组合的影响。葡萄糖较蔗糖能更有效地促进紫草素的产生,它们的最适浓度均为6％。LH和CH能抑制紫草素的产生,CH浓度大于0.02％时能抑制愈伤组织的生长,LH对生长无明显影响。椰乳浓度为10％时,能明显地促进紫草素的产生,紫草素的含量是对照的24倍。     

卫星搭载红豆草后代中耐盐细胞系的筛选及鉴定

将红豆草种子搭载于940703返地卫星,经田间繁殖得后代种子,先将种子在1.5%NaCl上筛选、并在该盐浓度下诱导愈伤组织和筛选,在无盐培养基上恢复生长后再在1.2%NaCl上筛选得到耐盐变异系.变异系具有正常的分化能力并表现出对PEG胁迫的交叉抗性.变异系在无胁迫条件下脯氨酸含量较低但在有盐胁迫时具有高效积累脯氨酸的能力.后者可能对红豆草耐盐系更为重要.变异系中脯氨酸的这种合成机理可能是由于一些基因在调控中对水的敏感性改变引起.梯度聚丙烯酰胺凝胶电泳表明耐盐系的SOD和酯酶分别出现175kD和75kD的新形式.说明空间诱变和组织培养相结合可以筛选耐盐变异系.     

Manganese toxicity to different growth processes in vitro in Nicotiana

Manganese toxicity to germination, callus induction and shoot regeneration was studied on three cultivars of Nicotiana tabacum: BEL W3, Burley 21, Bright NC 944. All materials were cultured on MS solid medium containing 0.1 (control), 2, 5, 10, 15 and 20 mM Mn, to which 5 μM NAA and 5 μM kinetin were added for callus induction and shoot regeneration. Mn toxicity to callus growth was tested using habituated callus of Nicotiana bigelovii var. bigelovii grown on MS medium without growth regulators. Mn concentrations higher than 2 mM were toxic for germination, and concentrations higher than 5 mM were toxic for callus induction, shoot regeneration and callus growth. Among the cultivars examined, Bright tobacco appeared more tolerant to high Mn concentrations during callus formation and shoot regeneration. However, many regenerated plants capable of growing in vitro in the presence of 2 and 5 mM Mn were obtained. This revised version was published online in June 2006 with corrections to the Cover Date.