香蕉组织培养过程中内生菌污染的控制

研究了体外培养一种孟加拉传统香蕉（Musa spp. Cv. Kanthali）的茎尖组织。茎尖的原始细胞表面经无菌处理（0.1% HgCl₂处理12min）,接种6～15d后外植体地下茎部分仍有微生物污染（大部分是细菌）,杀死了85％的外植体。为确定无污染培养基,将等量外植体分别浸泡在含400mg/L氨苄青霉素和200mg/L庆大霉素（两种光谱抗生素）的培养基中1h。结果表明,经抗生素处理的外植体完全没有污染,但培养3周后不能再生。进行二次继代培养后,其中一部分外植体吸收了培养基并胀大,颜色由苍白转变成浅绿或深绿。三次继代培养后数天,不再观察到外植体的生长,所有经抗生素处理过的外植体都开始死亡。在未经抗生素处理的活外植体中,单个茎发育的最佳培养基是：MS+4.0mg/L BA+0.5mg/L KT+15% CW,平均生长时间为18～21d,但再生率很低,只有30％。茎细胞增殖的最佳培养基是：MS+4.0mg/L BA+2.0mg/L IAA+15% CW,每个茎平均只萌发3～4个芽。最后,在添加0.5mg/L IBA的一半浓度的MS培养基中,体外培养茎最大生根率达到90％。     

黄山药丛生芽诱导与植株快速繁殖

采用黄山药的带芽茎段为外植体,试验了不同激素处理对芽诱导的影响,通过继代培养诱导丛生芽使大量增殖,经诱导生根和炼苗移栽而完成植株的快速繁殖再生。结果表明,MS 6-BA2.0mg/L NAA0.5-1.0mg/L为芽诱导的最适培养基,MS 6-BA1.0mg/L NAA0.5-1.0mg/L为继代增殖的最佳培养基,月增殖系数约为3倍,1/2MS 1BA0.5mg/L培养基诱导生根相对较好,诱导率为50%,组培苗经炼苗后,移栽成活率可达80%。     

杜仲叶片和叶柄愈伤组织的诱导和植株再生

本实验以5~6年生杜仲叶片及叶柄为外植体,研究了杜仲愈伤组织诱导及植株再生的方法。结果表明:接种于补加NAA(2.0~4.0 mg/L)或BA(1.0 mg/L)+NAA(2.0~4.0mg/L)的MS培养基上的叶片和叶柄,经21~28d培养后,脱分化形成绿色或浅绿色致密愈伤组织,频率达到70%以上。绿色致密愈伤组织在补加BA(2.25~2.75 mg/L)+NAA(0.15 mg/L)的MS培养基上经过1~2次继代之后,即出现茎芽分化,频率在15%以上,只是其中许多都是畸形苗,正常苗频率较低。此问题尚在研究之中。选择生长健壮的再生植株,切除其基部愈伤组织,然后将切口浸泡在250mg/L无菌ABT生根粉溶液中3~5sec,再插入1/4强度无激素MS培养基中, 2~3周后,在苗基部长出1~3条白色粗壮的不定根,生根频率在60%以上。     

新疆天山雪莲体胚诱导与分化研究

以新疆天山雪莲的叶片为外植体,分别用不同配方培养基诱导愈伤组织,后进行体胚诱导和分化培养形成再生雪莲植株.结果表明,诱导愈伤组织的最适培养基为MS 2,4-D 0.5 mg/L BA 1.5 mg/L,诱导率可达到100%;愈伤组织转移至MS 2,4-D 0.5 mg/L BA 1.5 mg/L培养基进行继代培养,增殖后的愈伤组织转移到MS 2,4-D 0.2 mg/L的液体培养基后成功诱导出雪莲体胚,出胚率达40%;将体胚接至MS ABA 0.5 mg/L培养基后,结果分化生长出大量的再生雪莲幼苗.     

树莓的组织培养及快速繁殖

以树莓的茎尖为外植体进行组织培养,筛选出各培养阶段适宜的培养基分别为:(1)丛生芽诱导:MS 6-BA 1.0 mg/L;(2)继代培养:MS 6-BA 0.5~1.0 mg/L;(3)生根培养:1/2MS NAA 0.2mg/L或1/2MS IBA0.2 mg/L。     

滇黄芩器官发生与不同继代次数遗传稳定性的RAPD分析

本研究以滇黄芩不带腋芽茎段为外植体,采用不同配比激素的MS培养基建立了滇黄芩器官发生,植株再生体系.结果表明,茎段在MS+6-BA 2 mg/L+NAA 0.5 mg/L培养基上培养时,愈伤组织诱导率达到100%:以相同培养基进行分化,并在MS+6-BA 2 mg/L+NAA 0.2 mg/L培养基上扩繁丛生芽.在1/2MS+IBA 0.2 mg/L培养基诱导生根,扦插继代.利用RAPD分析不同继代次数再生植株,所用的39条随机引物中只有1条引物带型发生变化.说明经组织培养获得的再生植株遗传稳定,可多次继代培养,为滇黄芩进一步遗传操作和扩大药材资源奠定基础.     

峨眉姜花离体培养与快速繁殖(简报)

以峨眉姜花地下茎茎尖为外植体,在MS+6-BA 8.0~10.0 mg/L+NAA 0.2 mg/L培养基上可诱导不定芽,在MS+6-BA 4.0 mg/L+NAA 0.2 mg/L+3%蔗糖培养基上进行增殖培养,在1/2 MS+IBA 0.5 mg/L+2%蔗糖培养基上进行生根培养后移栽入珍珠岩:泥炭(1:1)的混合基质中,成活率达87%。     

红根草的组织培养与快速繁殖研究

研究了红根草不同采集季节、外植体类型与消毒效果,不同激素浓度和激素组合与芽及根的诱导,及试管苗的移栽。结果表明,不同外植体类型消毒效果为茎节>茎尖>植株抽茎前的生长点;4~6月份采样最佳;MS+BA0.8~1.6mg/L+NAA0.2mg/L、MS+BA0.2mg/L+NAA0.02mg/L、MS+NAA1.0mg/L分别用于初代、继代、生根培养效果最好;试管苗移栽成活率达90%。     

罗汉果组培繁殖的技术要点

报道罗汉果组培繁殖的各项主要技术要点,包括组培条件、培养基的配制、外植体的选取与消毒、接种与培养、种源保存、炼苗与移栽、苗木包装与运输等。提出了5种培养基参考配方,即茎段诱导培养:MS+BA0.5～1.0mg/L+IAA(NAA)0.05～0.1mg/L+白糖3%+琼脂4.5g/L,pH5.8;茎尖诱导培养:MS+BA0.5～1.0mg/L+NAA0.05～0.1mg/L+椰子水100mL+白糖3%+琼脂4.5mg/L,pH5.8;继代培养(丛生芽方式):MS+BA0.3～0.7mg/L+NAA0.05/IAA0.1mg/L+白糖3%+琼脂4.5mg/L,pH5.8;继代培养(微型扦插方式):MS+BA0.1mg/L+IAA0.3mg/L+活性炭0.07g/L+白糖3%+琼脂4.5mg/L,pH5.8;生根培养:MS+BA0.07mg/L+IBA0.15mg/L+IAA0.1mg/L+活性炭0.1g/L+白糖3%+琼脂4.5mg/L,pH5.8。分析了外植体培养过程中可能出现的不良状况的原因并提出预防措施,明确了炼苗移栽的适宜条件并制定出相应的管理方法。形成了一套较为完整的罗汉果组培苗繁殖生产技术规程。     

罗布麻离体培养及快繁技术的研究

采用野生罗布麻(Apocynum venetamL.)顶芽及芽下茎段为外植体进行离体培养及快繁技术优化的研究。结果表明:适宜罗布麻离体培养的基本培养基为MS,适宜外植体起始分化的培养基为:MS BA 1.8mg/L KT 0.5mg/L,分化率为88.9%以上;适宜茎段增殖的培养基为MS BA 2.0mg/L KT 0.5mg/L,繁殖系数最高达5.67倍,通过切段繁殖还可提高繁殖系数3倍;适宜生根的培养基为MS IBA 0.5mg/L NAA 0.02mg/L,生根率达90%以上。     

In vitro propagation of Dendrobium macrostachyum Lindl.--a threatened orchid

In vitro propagation of Dendrobium macrostachyum, a threatened and endemic species was achieved through nodal explants. The nodal explants were cultured on Murashige and Skoog (MS) basal medium and MS medium supplemented with N6-benzyladenine (BA-2.22, 4.44 and 8.88 microM), Kinetin (KN-2.32, 4.65, and 9.29 microM) and Coconut water (CW, 5, 10 and 15%) individually or in combination with 2.69 microM alpha-naphthalene acetic acid (NAA). Axillary shoots were induced directly from nodal explants in medium containing BA, KN or CW. Optimal shoot induction (6 shoots/explant) was attained from nodal explants cultured on medium supplemented with 15% CW. Well developed shoots rooted at an average 5 roots per shoot in half strength MS medium devoid of any growth regulators.     

Micropropagation of Elaeocarpus robustus Roxb.

Multiple shoots were obtained from shoot tips and nodal explants of 20-year-old trees of Elaeocarpus robustus on Murashige and Skoog's medium supplemented with 0.5 mg l^–1 each of BA and Kn. Explants taken from in vitro-proliferated shoots subsequently produced multiple shoots when cultured on the same basal medium containing 0.5 mg l^–1 each of BA and Kn. Repeated subculture resulted in rapid shoot multiplication at an average rate of 10 new shoots per subculture. The addition of CM (10%) and CH (100 mg l^–1) to the medium enhanced the number of shoots up to 20 per subculture and increased the length of shoots. In vitro-raised shoots were rooted on half-strength MS medium containing 1.0 mg l^–1 IBA and 0.5 mg l^–1 IAA. Following transplantation in the field 85% of the plantlets survived and grew uniformly. Received: 17 March 1995 / Revision received: 30 December 1997 / Accepted: 9 January 1998     

Efficient TDZ-induced regeneration from capitulum explants of Gerbera jamesonii Bolus ex Hooker F. - an ornamental plant with high aesthetic value

Gerbera jamesonii Bolus ex Hooker F. (Asteraceae), a most prominent ornamental plant ranking fifth in the world cut flower market has gained huge demand across the globe for its high aesthetic value. In the present study, an efficient plant regeneration protocol was developed using capitulum explants from the field grown mature plants of G. jamesonii. A successful surface sterilization procedure was established using a series of sterilants without affecting explant regenerability. The culture of capitulum explants on Pre-culture Induction Medium [(PIM), Murashige and Skoog (MS) medium fortified with 0.5?mg/L thidiazuron (TDZ) in combination with low levels of auxins] for a period of 2 weeks in dark conditions was crucial for inducing morphogenetic response. Upon transfer onto Shoot Regeneration Medium [(SRM), MS +4.0?mg/L 6-benzyladenine (BA) and 0.2?mg/L NAA], explants has significantly produced highest number of shoots (16?±?0.33). Incubation for 18–21?days on Shoot Multiplication and Elongation Medium [(SMEM), MS +2.0?mg/L BA +0.2?mg/L NAA] resulted in the highest number of multiple shoots (22.00?±?0.93) with increased mean shoot length (3.49?±?0.08). In vitro elongated shoots were rooted (95%) on ½ MS +1.0?mg/L indole-3-acetic acid (IAA) within 10–12?days and fully rooted plants were transferred to poly-house for hardening with 90% survival rate.     

Micropropagation ofFagus sylvatica L.

Summary An in vitro shoot multiplication system was established from juvenileFagus sylvatica L. tissues, and plantlets were regenerated. Embryonic axes were excised from beech seeds and germinated in vitro on media supplemented with 6-benzyladenine (BA) to obtain plantlets with axillary shoots. Shoot multiplication was maintained by sequential subculture of axillary shoot tips and basal segments on Woody Plant Medium supplemented with 0.5 mg/liter BA+2 mg/liter zeatin+0.2 mg/liter naphthaleneacetic acid (NAA). The effeciency of shoot multiplication clearly depended on the kind of explant used. Transfer to fresh medium every 2 wk during the 6-wk multiplication cycle improved multiplication rates. In the rooting stage, an initial 7-day dark period significantly improved rooting capacity and accelerated the emergence of roots on auxin-treated shoots. Adventitious buds were induced on the intact hypocotyls of the whole plantlets derived from the initial embryonic axis explants, especially on those cultured on medium with 1 mg/liter BA. Cotyledon and hypocotyl segments isolated from seedlings grown in vitro from embryos also exhibited capacity for adventitious bud formation, especially when cultured on media supplemented with 0.5 mg/liter BA + 0.1 mg/liter NAA.     

Silver nitrate and aminoethoxyvinylglycine promote in vitro adventitious shoot regeneration of pomegranate (Punica granatum L.)

A protocol is presented for direct adventitous shoot organogenesis and complete plant regeneration from seedling-derived explants of pomegranate (Punica granatum L.), a tropical fruit tree. Murashige and Skoog (1962) (MS) medium enriched with 8.9 mumol/L benzyladenine (BA), 5.4 mumol/L naphthaleneacetic acid (NAA) and 10% coconut water (CW) induced adventitious shoot bud differentiation in axenic seedling-derived cotyledons as well as hypocotyl segments. The cotyledons were more responsive than the hypocotyls. Addition of ethylene inhibitors such as AgNO3 (10-40 mumol/L) and aminoethoxyvinylglycine (AVG) (5-15 mumol/L) to the medium markedly enhanced regeneration frequency as well as number of shoots obtained per explant. The promotive effect of AVG and AgNO3 on shoot organogenesis was observed only in cotyledon explants. The regeneration medium containing AgNO3 (20 mumol/L) or AVG (10 mumol/L) induced adventitious shoot buds from 57% or 53% of the cotyledon explants respectively. These shoot buds developed into shoots upon transfer to a regeneration medium without AgNO3 and AVG. The promotive effect of AVG on shoot regeneration was reversed by exogenous application of 20 mumol/L 2-chloroethylphosphonic acid (CEPA), an ethylene releasing compound. On the other hand, shoot regeneration stimulated by AgNO3 was relatively less affected by CEPA. Regenerated shoots were rooted in half-strength MS medium (1/2 MS) containing 0.54 mumol/L NAA. The well rooted plantlets were acclimatized and eventually established in soil.     

In vitro induction of multiple shoots and plant regeneration from shoot tips of mung bean (Vigna radiata (L.) Wilczek)

Conditions for plant regeneration from excised shoot tips of Vigna radiata were studied. Complete plants were regenerated directly without an intervening callus phase from shoot tips on basal medium (MS salts+B₅vitamins). Regeneration frequency varied with genotype, explant size and growth regulator combinations in the medium. Addition of cytokinins induced a variable amount of callus at the base of the shoot tip, followed by multiple shoot formation. Benzyladenine (BA), kinetin and zeatin at 5×10^-6 M each induced multiple shoots in 100% of the explants but the highest number of regenerants per explant (9) was produced with BA. The efficacy of BA for shoot multiplication was not improved when it was supplemented with naphthaleneacetic acid (NAA) or indoleacetic acid (IAA). NAA or adenine sulphate, when applied alone, induced complete plantlets. The growth regulator requirement of explants for the induction of multiple shoots varied with explant size. The shoot tip explants maintained proliferation ability on subculture. None of the treatments was effective in inducing shoot bud differentiation from callus. Regenerated shoots were rooted on MS basal medium and MS supplemented with either IAA or indolebutyric acid. The rooted plants were transferred to the field; 60% subsequently survived and grew.Abbreviations BM basal medium [MS (Murashige & Skoog 1962) salts+B₅ (Gamborg et al. 1968) vitamins] - BA 6-benzyladenine - AdS adenine sulphate - IAA indole-3-acetic acid - NAA-1 naphthaleneacetic acid - IBA indolebutyric acid     

一种快速有效的741杨离体叶片再生芽方法

在对杂交品种741杨(Populus alba(P.davidiana×P.simonii)×P.tomentosa)进行农杆菌介导法转基因的试验中发现了一种快速有效的叶片再生芽的方法.首先叶片外植体在培养基Ⅰ(MS培养基添加0.5 mg/L BA和1.0 mg/L 2,4-D)上培养2～3 d,再转移到培养基SH(MSmedium containing 2.0 mg/L of BA and 0.1 mg/L of NAA)上培养10 d,然后再转移到培养基Ⅱ(MSmedium with 0.5 mg/L of BA)上,培养大约5 d之后86.7%的叶片外植体产生的芽,每片叶片外植体(1 cm×1 cm)可产生40～50个芽.但是,如果叶片外植体在培养基Ⅰ上培养的时间长于5 d,再依次转移到培养基SH和Ⅱ上,则叶片会产生大量根.     

In vitro propagation of Dendrobium hybrids using flower stalk node explants

Large-scale in vitro propagation protocol for Dendrobium hybrids Sonia 17 and 28, two highly prized commercial cut flower cultivars through shoot multiplication using flower stalk node explants and protocorm-like bodies (PLBs) formation was accomplished. Both hybrids did not exhibit significant differences in initiation, multiplication, rooting, and field establishment. Flower stalk nodes cultured on half strength Murashige and Skoog (MS) medium supplemented with 6.97 microM kinetin (Kn), or 15% coconut water (CW) or 13.3 microM of N6-benzyladenine (BA) evoked bud break. Kn showed better growth of the initiated bud. Excision and culture of the initiated shoots on medium having same amount of Kn developed more than 5 shoots per shoot directly from the base. Subsequent culture enhanced the rate of shoot induction. Transfer of isolated shoots onto 44.4 microM of BA enriched medium displayed induction of more than 6 PLBs from the base within 60 days. PLBs underwent rapid multiplication upon transferral to medium having the same concentration of BA (44.4 microM). Subsequent culture increased the proliferation of PLBs. No decline was observed in the proliferation of shoots as well as PLBs up to 15th subculture. PLBs transferred onto half strength MS medium with 6.97 microM of Kn underwent conversion of more than 90% PLBs to shoots. The shoots were rooted at the best on half strength MS medium with 2 g l(-1) activated charcoal. Survival rate of the plantlets of the two hybrid cultivars after acclimatization was more than 80%.     

A micropropagation protocol forCinnamomum camphora

Summary A micropropagation protocol was developed forCinnamomum camphora (L.) Sieb., using as initial explants 3–5-mm shoot tips from newly emerged laterals of 2-yr-old trees. Performance of small shoot tips was compared with that of 2.0-cm nodal segments during subculture. Murashige and Skoog medium (MS) supplemented with different concentrations of N₆-benzyladenine (BA) or thidiazuron (TDZ) was used to examine shoot proliferation. In separate experiments, MS was supplemented with 1-naphthaleneacetic acid (NAA) for rooting of shoots, and the commercial preparation EM₂ for prevention of hyperhydricity. BA stimulated shoot formation and callus development, whereas TDZ promoted only callus development. Both cytokinins induced hyperhydricity when small shoot tips were used, with severity being directly related to concentrations. Hyperhydricity was avoided in subcultures by using larger nodal segments. EM₂ did not alter degree of hyperhydricity but suppressed callus development and strongly promoted shoot multiplication. The number of new shoots after a 6-wk subculture was 9 per nodal segment when supplemented solely with 4.4 μM BA and 18 per segment when further supplemented with 1000 mg EM₂ per I. Rooting of shoots occurred best when supplemented solely with 0.54 μM NAA, averaging 7 roots per shoot in 4 wk. Ninety percent of rooted shoots survived transfer to the greenhouse.