Direct differentiation of ears and tassels from cultured shoot apices of maize

In vitro morphogenesis of inflorescences from the cultured corn seedling shoot tips was obtained on modified Murashige and Skoog (MS) medium in complete darkness. Some shoot tip meristems excised from seedlings of inbred line 515, inbred line 8112 and their filial generations would directly give rise to florets on modified MS medium supplemented with 2.0 mg/L N6-bezyladenine (6-BA) in five or six weeks. On the medium with 1.0 mg/L 6-BA and 0. 2 mg/L 2, 4-dichlorophenoxy acetic acid (2, 4-D), the explants swelled first, and produced multiple shoot clumps, then the culture of the shoot tips from all of the six inbred lines in experiment would ultimately initiate to develop ears and tassels accompanied by multiple shoot clumps developing on the medium with 1.0 mg/L 6-BA and 0. 2 mg/Lin-dole-3-butyric acid (IBA). The developmental patterns of the corn inflorescences were similar to the controls of normal plants in the field, but the number of the ears was much more than that of the tassels in vitro. It seem     

太子参‘柘参1号’离体快繁试验

以太子参‘柘参1号’叶片、茎段为外植体进行离体快繁试验,结果表明：带腋芽的茎段能够诱导出丛生芽,且诱导率较高,最佳诱导培养基为MS + 6-BA 1.0 mg/L + NAA 0.2 mg/L +蔗糖30 g/L;增殖培养基为MS + 6-BA 1.0 mg/L + NAA 0.2 mg/L +蔗糖30 g/L;生根培养基为MS + NAA 0.2 mg/L +蔗糖30 g/L。     

大花美人蕉茎尖组织培养技术研究

以大花美人蕉(Canna×generalis)根茎茎尖为外植体进行组织培养技术研究,筛选出芽诱导适宜的培养基为MS+6-BA 8.0mg/L (单位下同)+TDZ 0.03;MS+6-BA 8.0+TDZ 0.03+NAA 0.1培养基能较好地诱导分化出丛生芽,继代增殖培养中与MS+6-BA 3.0+TDZ 0.03+NAA 0.1培养基交替使用可减少畸形芽,增殖系数达1.67;适宜的生根培养基为MS+6-BA 1.0+NAA 0.5,生根率达66.67%,且植株生长健壮,移栽易成活。     

In-vitro morphogenesis of corn (Zea mays L.)

The objective of this research was to study the in-vitro morphogenetic pattern of corn (Zea mays L.) shoot tips excised from aseptically-grown seedlings, and of expiants of axillary shoot buds, immature tassels and ears (staminate and pistillate inflorescences) obtained from greenhouse-grown corn plants. The seedling shoot tips and immature ears first regenerated clumps of multiple shoots within four weeks of culture on Murashige and Skoog (MS) basal medium supplemented with 500 mg/L casein hydrolysate (CH) and 9.0 M N⁶-benzyladenine (BA). Multiple shoot clumps were also differentiated from spikelets of immature tassels cultured on MS medium containing 500 mg/L CH, 4.5 M BA and 0.45 M 2,4-dichlorophenoxy acetic acid (2,4-D). All these multiple shoot clumps in turn differentiated clusters of ears after further four subcultures at four-week intervals under light on MS medium supplemented with 500 mg/L CH and 2.25, 4.5, 9.0 or 18 M BA. Axillary shoot buds readily differentiated clusters of ears within four weeks of the initial culture on these media. Secondary and tertiary ear clusters were initiated following subculture of primary ears on MS medium containing 500 mg/L CH and 4.5 or 9.0 M BA. Most of the ear primordia developed into ears with well-developed ovaries and styles on subculture on MS medium containing 500 mg/L CH and 1.0 M BA. Corn kernels were obtained after pollination of in-vitro-formed ears with pollens collected from greenhouse-grown corn. These kernels germinated in vitro and developed into mature corn plants in the greenhouse. Clusters of tassels were also differentiated in darkness from the multiple shoot clumps after six months successive subcultures but the spikelet primordia of tassels failed to develop fully under the in-vitro conditions tested. Somatic embryos arose directly from spikelet primordia of young tassels or ears on MS medium containing 500 mg/L CH and 4.5 M 2,4-D, or indirectly from calli derived from spikelets of young tassels and ears on MS medium containing 500 mg/L CH and 9.0 M 2.4-D.Abbreviations BA N⁶-benzyladenine - CH casein hydrolysate - 2,4-D 2,4-dichlorophenoxyacetic acid - IBA indole-3-butyric acid - MS Murashige and Skoog (basal medium) Heng Zhong is a Rockefeller Foundation Fellow on leave from the Institute of Botany, Academia Sinica, Beijing, P.R. China. This work was supported by a grant from the MidWest Plant Biotechnology Consortium and U.S.-A.I.D. grant No. DAN-4197-A-00-1126-00 to M.B. Sticklen. Thanks are due to Illinois Foundation Seeds, Champaign, USA for the supply of Honey N Pearl sweetcorn seeds and the Services of Center for Electron Optics, Michigan State University, for the electromicroscopic work as related to this publication.     

激素对洋桔梗植株再生的影响及生根培养的研究

以MS为基本培养基 ,附加不同浓度的 6 BA、KT、NAA和IBA诱导洋桔梗叶片外植体的再生植株。结果表明 :MS +6 BA 0 .5～ 1 .0mg/L(单位下同 ) +NAA 0 .2和MS +6 BA 0 .5～ 1 .0 +IBA 0 .2培养基都能诱导外植体产生愈伤组织 ,但 6 BA的浓度必须小于 1 .0mg/L ,否则会导致组织的严重玻璃化 ;MS +KT 1 .0～2 .0 +NAA 0 .2或MS +KT 1 .0～ 2 .0 +IBA 0 .2培养基也能诱导外植体产生愈伤组织 ,愈伤组织出现的时间较早且质地较好 ,适合分化。继代培养时 ,MS培养基中仅加 6 BA 0 .5mg/L或KT 0 .5mg/L ,即能获得较高的分化率。生根培养研究中 ,培养液为 1 /2MS+5 0g/L糖 +IBA 2mg/L的前处理 ,生根效果较好 ,生根率接近基质生根培养的生根率。     

草莓高频离体再生体系的研究

以6个草莓品种为试材,研究了影响草莓不定芽再生的各种因素,建立离体叶片高效再生系统。结果表明,外植体基因型、激素种类及配比、叶龄等是影响草莓再生的主要因子,其中‘鬼露甘’叶片最佳芽诱导培养基为MS 2.0 mg/L 6-BA 0.1 mg/L IBA,‘嫜姬’叶片愈伤组织的诱导以MS 3 mg/L 6-BA 0.2 mg/L 2,4-D较好,而且1周左右的暗培养可以防止外植体的褐化。芽伸长的最适培养基为MS 0.5 mg/L 6-BA 0.5 mg/L IBA,生根的最适培养基为MS 0.2 mg/L IBA,试管苗移栽后成活率为87%。     

藏药纤毛婆婆纳的愈伤组织诱导和快速繁殖研究

以纤毛婆婆纳（Veronica ciliateFisch.）无菌苗的顶芽作为外植体,在不同激素和浓度组合的MS培养基上进行愈伤组织诱导和快速繁殖的研究。结果表明,愈伤组织诱导的最佳培养基为：MS＋6-BA 0.5 mg/L＋NAA1.0 mg/L,诱导率达到95%;顶芽在MS＋6-BA 0.5 mg/L＋NAA 0.1 mg/L增殖培养基中增殖效果最佳,增殖系数高达5.4;丛生芽在1/2 MS＋IBA 0.05 mg/L生根培养基生根效果最好,不仅根的质量好,而且生根率也达到95%;此再生苗的移栽成活率也最高,在适宜条件下可达40%。     

2种菊苣再生体系及遗传转化效率的比较

以普那菊苣和将军菊苣子叶为材料,通过植物组织培养的方法,探讨了不同激素浓度配比对二者愈伤组织诱导、芽分化以及根再生的影响,并通过农杆菌介导法将编码獐茅液泡膜Na+/H+逆向转运蛋白基因(AlNHX)导入菊苣中,比较普那菊苣和将军菊苣的遗传转化效率。结果表明:不同基因型的菊苣愈伤组织诱导和芽分化条件不同,普那菊苣最佳培养基为MS+1.5mg/L 6-BA+0.2mg/L IBA;将军菊苣最佳培养基为MS+1.0mg/L 6-BA+0.5mg/L NAA;二者最佳生根培养基均为1/2MS+0.1mg/L NAA。获得的抗性芽经PCR检测,初步证实AlNHX已插入到菊苣基因组中,且普那菊苣转化效率为10.0%,将军菊苣转化效率为13.3%。     

野生资源植物金荞麦离体快繁技术研究

针对金荞麦野生资源开发利用情况,试验以茎段为外植体,系统地探讨了以组织培养为手段进行快速繁殖的途径。结果发现：①外植体用HgCl2的消毒时间为6 min;②初代培养时培养基可选择MS＋1.0 mg/L6-BA＋0.5 mg/L NAA＋30 g/L蔗糖;③继代培养时培养基可选择MS＋1.0 mg/L 6-BA＋0.2 mg/L NAA＋30 g/L蔗糖;④生根培养时培养基可选择MS＋0.5 mg/L NAA＋20 g/L蔗糖。     

春石斛丛生芽组培快繁研究

本试验采用正交设计,探讨春石斛组培以丛生芽途径进行快速繁殖的方法。研究主要集中在不同基本培养基类型、不同生长调节剂配比及不同添加物等因素对丛生芽增殖的影响,从中筛选最优技术参数组合,提高丛生芽增殖系数,建立春石斛最优再生体系。结果表明：影响丛生芽增殖的显著因子分别是基本培养基、6-BA、KT;最适宜的培养基配方是1/2 MS + 6-BA 1.0 mg/L + NAA 1.0 mg/L + KT 0.5 mg/L +蔗糖30.0 g/L +琼脂7.0 g/L +椰汁150.0 ml/L,pH 5.4。此外,春石斛丛生芽增殖的外植体以1.5 cm带节茎段、接入密度每瓶3株较适宜。     

睡菜离体快繁技术的研究

以睡菜的幼嫩茎段为外植体,接种到附加不同浓度激素配比(6-BA/NAA)的MS培养基,诱导睡菜愈伤组织、芽及根的生长。研究发现,外植体在1.0mg/L 6-BA+0.1mg/L NAA+MS的培养基上培养10d,可观察到浅绿色的愈伤组织。愈伤组织转接到4.0mg/L 6-BA+0.3mg/L NAA+MS培养基上2周左右可生成芽。对带芽的愈伤组织再进行诱导生根进而形成完整再生植株,最适根诱导培养基为0.3mg/L 6-BA+1.0mg/L NAA+MS培养基。该实验采用植物离体快繁技术成功建立了睡菜再生体系,为睡菜种苗规模化奠定了技术基础。     

药用植物金荞麦愈伤组织诱导与植株再生

目前转基因技术已成为植物定向遗传改良的重要手段,而建立稳定高频的离体再生系统是实现遗传转化的基础和前提.本试验以25 ～30 d苗龄的金养麦(Fagopyrum dibotrys)无菌苗叶片、茎节间、叶柄为外植体进行愈伤组织诱导与植株再生研究.结果表明:叶片在MS +2,4-D 4.0 mg/L +6-BA 1.0 mg/L培养基上愈伤组织诱导率达到89％.茎节间在MS +2,4-D 2.0 mg/L +6-BA 2.0 mg/L培养基上愈伤组织诱导率为87％.叶柄在MS +2,4-D 4.0 mg/L +6-BA 2.0 mg/L+ IBA 0.2 mg/L培养基上的最高诱导率仅为54％.愈伤组织分化不定芽的适宜培养基为MS +6- BA2.0 mg/L +TDZ0.2 mg/L +NAA0.2 mg/L;金荞麦不定芽在1/2 MS +NAA 0.5 mg/L的培养基上生根效果最好.组培再生植株经炼苗后移栽到田间成活率达80％以上,且生长表现正常.高频完整再生体系的建立,为金荞麦进一步遗传操作和扩大药材资源奠定了基础.     

亳芍茎尖组织培养的研究

选取亳芍茎尖为试验材料,探究不同培养条件对亳芍组织培养的影响,结果表明:亳芍茎尖在1/2MS+6-BA 1.0 mg/L培养基上培养39 d后,茎尖分化出芽的同时也形成较多的丛生芽;丛生芽在1/2MS+6-BA1.0mg/L培养基上增殖速度最快;来自不同启动培养基上的丛生芽在相同培养基上,接种15 d后观察,不同来源的丛生芽长势不同,30 d后仍存在一定的差异;幼苗在1/2MS+IBA 0.1生根效果最好。     

罗布麻愈伤组织诱导及植株再生

以罗布麻(Apocynum venetum L.)当年的成熟种子和5周龄的幼苗叶片为外植体,研究了不同激素组合、暗培养对愈伤组织及植株再生的影响.结果表明,幼苗作外植体诱导愈伤的最佳培养基为添加1.0 mg/L 6-BA 0.2 mg/L IBA的MS培养基;继代培养中1.0 mg/L 6-BA与0.2 mg/L IBA组合愈伤致密而生长迅速,长时间培养硬化的愈伤组织可用添加0.5 mg/L 6-BA和0.1 mg/L IBA培养基和初期暗培养获得大量质地疏松、增殖迅速的愈伤组织;再生苗诱导以0.5 mg/L 6-BA 0.2 mg/L IBA组合为佳;1/2MS附加NAA 0.6 mg/L为适宜的生根培养基,初步建立了罗布麻离体再生体系.     

广西绞股蓝的组织培养和快速繁殖

广西绞股蓝是极具开发潜力的绞股蓝属植物。以其茎尖和叶片为外植体进行的组织培养试验表明,茎尖为最适的外植体,愈伤组织诱导和不定芽增殖的最适培养基为MS+6-BA 1.0mg.L-1+NAA 0.02mg.L-1,在此培养基中,茎尖和叶片的愈伤组织诱导率平均达95%,丛芽增殖系数平均达14。广西绞股蓝最适的生根培养基为MS+NAA 0.20mg.L-1,生根率92.50%。炼苗后组培苗的移栽成活率达95.5%。     

Optimization of in vitro multiple shoot clump induction and plantlet regeneration of Kentucky bluegrass (Poa pratensis)

An efficient protocol for Kentucky bluegrass (Poa pratensis L.) in vitro culture was established using shoot apices of seedlings as explants. The optimal procedure of this protocol for majority of the genotypes was that meristematic cell clumps and small calluses were firstly induced from the bases of explants on initial culture medium supplemented with 0.9 μM 2,4-d and 8.9 μM 6-BA for 20 d, then were separated and transferred to shoot clumps induction medium containing 8.9 μM 6-BA for the formation of multiple shoot clumps. The percentage of multiple shoot clumps and numbers of shoots per clump were deeply related with the combinations of different plant growth regulators, duration of initial culture, the intensity of illumination and genotypes. Histological observation of the induced explants revealed that the meristematic cell clumps were produced from repeated division of the cortical cells and original meristematic primodium cells of explants, and the multiple shoots were formed via organogenesis pathway in the meristematic cell regions of cultures on shoot clumps induction medium. In this study, plantlets were efficiently regenerated on large scale from seven cultivars of Kentucky bluegrass. Hence the meristematic cell clumps and small calluses in this protocol could be considered good targets for genetic transformation of Kentucky bluegrass.     

洋甘菊组织培养及植株再生

洋甘菊种子灭菌后,置于MS 培养基上发芽形成无菌苗,发芽率可达80 %.适合洋甘菊种子的灭菌的方法是:75 %酒精30 s+3.5 %次氯酸钠15 min+2 %次氯酸钠10 min.在研究范围内,洋甘菊不定芽增殖的最佳培养基为MS+6-BA 1.5 mg/L+NAA 0.5 mg/L,碳源以蔗糖浓度3 %最佳.适宜洋甘菊生根的最佳培养基为MS+IBA 1.0 mg/L+NAA 0.5 mg/L+6-BA 0.2 mg/L.     

大豆离体培养及高频再生基因型的筛选

为建立一个高效的大豆再生体系用于大豆的遗传转化,选用3个东北主栽品种‘黑农35’、‘黑农41’和‘黑农58’的子叶节和胚尖作为外植体,分别建立了3个品种的子叶节和胚尖再生体系,并研究了6-BA对大豆再生的影响。结果表明,‘黑农41’子叶节最适芽诱导培养基为MSB5＋1.0mg·L-16-BA＋0.2mg·L-1IBA,胚尖最适芽诱导培养基为MSB5＋0.2mg·L-16-BA＋0.2mg·L-1IBA。‘黑农41’再生体系在出芽率、出芽数和芽伸长数上均远高于‘黑农35’和‘黑农58’,是一个优秀的大豆转基因受体材料。     

冬凌草离体培养体系的建立及主要次生代谢产物的测定

以冬凌草叶片为外植体,研究不同浓度激素组合对冬凌草愈伤组织诱导及植株再生的影响,并对不同外植体(茎、叶)诱导愈伤、芽的分化能力及再生植株内主要次生代谢产物的含量进行了比较研究。结果表明:在MS 2.0 mg/L 6-BA 1.0 mg/L NAA培养基上诱导愈伤组织效果较好;在MS 2.0 mg/L 6-BA的培养基上诱导芽的效果较好;叶片和茎段在愈伤诱导培养基上均能产生大量的愈伤组织,但其再分化能力以茎段最好;再生苗生根培养基以0.3 mg/L IBA最好;以叶为外植体诱导的再生植株中冬凌草甲素、迷迭香酸的含量均高于以茎为外植体诱导的再生植株。     

仙人掌果的组织培养

以仙人掌果的植株顶端幼嫩茎段为外植体,在添加NAA 0.5mg/L+6-BA 5.0mg/L的MS培养基中诱导产生丛生芽,在此培养基上继代培养,丛生芽数不断增加。在添加NAA 0.2mg/L+IBA 1.0mg/L的MS培养基上可正常长根。