杉木愈伤组织培养中的褐化控制研究

以杉木茎尖诱导形成的愈伤组织为试验材料,研究维生素C、柠檬酸、半胱氨酸、硫代硫酸钠4种抗氧化剂和活性炭对杉木愈伤组织培养中褐化的影响。结果表明：维生素C和半胱氨酸能有效地控制褐化的发生,且对愈伤组织生长没有明显的抑制作用,是杉木愈伤组织培养较为适宜的抗褐变剂。     

硝酸银对‘凤丹’牡丹愈伤组织褐变过程中酚类物质合成及相关基因表达的影响

以‘凤丹’牡丹的组培苗为材料,在含有0-5.0 mg/L硝酸银的基础培养基中进行培养后,通过测量总酚含量、单体酚种类及其含量的变化和相关基因的表达情况,确定不同浓度的硝酸银对抑制愈伤组织褐化的作用。结果表明,培养基中加入硝酸银能够抑制相关基因的表达,明显降低愈伤组织中多酚类物质的含量进而减轻植物组织褐变程度,其中2.0 mg/L的综合效果最好;硝酸银对组培苗褐变过程中产生影响的单体酚有绿原酸、芦丁、香豆酸、对香豆酸、表儿茶素、二氢槲皮素;硝酸银处理后的的愈伤组织中,转录因子MYB2、WD40-1、WD40-2与结构基因苯丙氨酸解氨酶(PAL)、黄烷酮醇还原酶(DFR)、查耳酮合酶(CHS)、查尔酮异构酶(CHI)、3-二氢黄酮羟化酶(F3H)、黄酮醇3'-羟化酶(F3'H)的表达量与褐变等级和总酚含量之间存在显著的相关性(P0.05)。     

马齿苋多糖提取物对翅果油树愈伤组织诱导的影响

采用传统热浸提工艺,从马齿苋植株中提取多糖.以B1培养基为基础,通过添加0.15 g/L的抗褐变剂Vc及不同浓度的马齿苋多糖,研究了其对翅果油树愈伤组织培养的抗褐变作用.结果显示:(1)马齿苋多糖对愈伤组织培养中的褐变有一定缓解作用.(2)经筛选,得到0.19 g/L为最适的多糖添加物浓度,子叶愈伤组织产生生物量最多,抗褐变效果与Vc的作用相似,愈伤组织生命周期也明显缩短.     

五种抗褐化剂对杜鹃兰原球茎增殖培养的作用效果

以杜鹃兰为试验材料,研究了硫代硫酸钠(Na_2S_2O_3)、维生素C(Vc)、谷胱甘肽(GSH)、活性炭(AC)和聚乙烯吡咯烷酮(PVP)对杜鹃兰原球茎褐化与增殖的影响。结果表明:在培养基中分别添加以上5种抗褐化剂对杜鹃兰原球茎褐化具有不同程度的抑制效果,且均能明显提高原球茎的增殖率。抗褐化效果以AC最佳,GSH次之;增殖效果以PVP最佳,GSH次之。培养基中添加GSH时,原球茎褐化率与多酚氧化酶(PPO)活性呈极显著正相关;添加PVP时,原球茎褐化率与总酚含量呈显著正相关。综合杜鹃兰原球茎生长状态、褐化和增殖指标的分析,GSH是5种抗褐化剂中较为理想的抗褐化剂。     

植酸在银杏组织培养中应用的研究

本文报道以植酸作抗氧化剂,对银杏愈伤组织抗氧化褐变的研究。结果表明:①植酸具有抑制多酚氧化酶活性的作用,从而有效地控制愈伤组织的褐变,促进愈伤组织生长;②不同的抗褐变剂,以0.1％的植酸效果最好;③不同的培养基以MT附加BA1.0 mg/L,NAA 3.0 mg/L的效果最好。     

几种培养基及光照对蝴蝶兰叶片外植体褐变的影响

蝴蝶兰叶片外植体在MS纸桥培养基上培养10 d发生褐变率较低,1/2 MS次之,MS、B₅和N₆培养基外植体褐变率最高。MS培养基中铁盐加倍或微量元素缺乏造成外植体严重褐变,培养基积累很多褐色物质;减少琼脂含量,外植体褐变加重;添加柠檬酸可减轻外植体褐变;而添加活性炭、抗坏血酸或PVP对减轻外植体褐变无显著作用。光照强度增加外植体褐变严重。     

降低卷丹百合组培褐变技术研究

以卷丹百合Lilium lancifolium鳞片为外植体,采用1/2MS+0.8 mg·L~(-1) 6-BA+0.2 mg·L~(-1) NAA为基本培养基,研究不同消毒时间的外植体消毒效果,探讨聚乙烯吡咯烷酮(PVP)、抗坏血酸(V?)、活性炭(AC)以及光、暗两种培养条件对卷丹百合组织培养过程中褐变的影响。结果表明,用75%酒精消毒30 s、0.1%HgCl_2消毒10 min、2%NaClO消毒6 min的消毒效果最好,污染率为33.33%,成活率和诱导率均为66.67%。在培养基中加入PVP、V?、AC和暗培养均能减轻褐变的发生,其中以4.5 mg·L~(-1) PVP处理对卷丹百合褐变的抑制效果最好,外植体褐变率最低为30%,愈伤组织诱导率为70%。     

常温条件下三倍体毛白杨的愈伤组织诱导和保存

在MS附加 0 .5mg·L-16 BA和 0 .15mg·L-1NAA的培养基上 ,三倍体毛白杨幼叶的愈伤组织诱导率可达 87.6 %。蔗糖浓度大小与愈伤组织增长量成正比 ,与褐变开始时间成反比 ,2 %蔗糖下 ,继代周期可长达 6 1d。每日光照 12h的愈伤组织褐化时间可延长至 82d ;少于 12h ,愈伤组织松散 ,褐变开始时间缩短。愈伤组织开始褐化后 ,再分化时间延长 ,分化率降低。不同继代周期对再生试管苗生根无影响。     

活性炭培养基对棉花愈伤组织诱导的效果(简报)

在含有NAA2mg/L、6-BA1mg/L的LS培养基中加入0.1％的活性炭,能有效地防止棉花愈伤组织的变褐老化,提高出愈率和愈伤组织活力。     

箭胡毛杨愈伤组织诱导、保存与再分化

本研究以箭胡毛杨幼叶为外植体,通过对愈伤组织的诱导、保存的再分化的研究,筛选出适宜的培养基和培养条件。外源激素6－BA与IAA的9种配比中,0．5／0．1对箭胡毛杨愈伤组织诱导率可达90％。蔗糖浓度的大小与愈伤组织增长量成正比,与褐变开始时间成反比,当浓度为2％时,继代周期可长达63d。适宜的光照时间可延长愈伤组织保存期并维持良好的组织结构：日光照14h,愈伤组织褐化时间可达到80d;日光照时间少于12h,愈伤组织松散,颜色黄白,褐变开始时间短。经较长时间保存后未褐变愈伤组织的胚状体和丛生苗分化发生时间与分化率不受继代周期影响。当愈伤组织开始褐化后,组织再分化时间延长,分化率大幅度降低。不同继代周期对再生试管苗的生根无影响。     

The Role of Antioxidants for Initiation of Somatic Embryos with Conostephium pendulum (Ericaceae)

Using Conostephium pendulum as a 'model' species in the Ericaceae a study was instigated to investigate the role of oxidative stress on the embryogenic competency of the explant tissue and callus. Three antioxidants were examined as an explant pre-treatment and incorporated in the growth medium. Pre-treatment of explant tissues with tri-potassium citrate and citric acid significantly reduced callus necrosis, however this treatment significantly reduced somatic embryo production when compared to preparing tissue under sterile distilled water. A combination of tri-potassium citrate and citric acid incorporated in the medium significantly reduced phenolic browning, however this treatment had no significant effect on the number of somatic embryos formed suggesting that prevention of tissue browning may be feasible by reducing the contact with oxygen during excision of tissues.     

苦丁茶愈伤组织的诱导与褐变抑制

以叶片为材料,对苦丁茶愈伤组织的诱导,继代培养及褐变调控的研究表明：（１）苦丁茶愈伤组织的诱导及继代培养均以ＭＳ附加ＢＡ ２．０ｍｇＬ＾－１和ＮＡＡ ４．０ｍｇＬ＾－１的培养基效果最好;（２）０．１％的植酸可明显促进愈伤组织生长、抑制褐变,而硫代硫酸钠效果最差;（３）连续培养４０－５０ｄ愈伤组织增长倍数达到最大值;（４）继代２７次以后愈伤组织生长速度开始下降。这些条件为下一步细胞培养生产苦丁茶甙等     

植酸对红豆杉细胞悬浮培养影响作用的研究

针对红豆杉细胞培养中经常遇到的褐变问题,以植酸做抗氧化剂,添加到悬浮细胞培养基中,能提高细胞鲜重,明显抑制细胞多酚氧化酶和过氧化物酶活性,从而有效地控制细胞褐变,促进红豆杉悬浮细胞生长。以005%浓度的添加效果最好。     

A Study on the Application of C17 Medium for Anther Culture

Media with varied levels of minor elements and KNO3, NH4NO3, KH2PO4, MgSO4·7H2O, CaCl2· 2H2O and Fe-Salts were screened to obtain high yield of callus from wheat anther by using orthogonal tests. Of all the seven minor elements treated, the one without NaMoO4·2H2O and with 11.2 mg/l MnS04·4H2O was found to be the most effective. Among the five kinds of organic materials tested, biotin appear- ed to have the highest influence on the induction frequency of anther callus and its opimum dosage was 1.5 mg/l. Based on these data, C17 medium was developed and its induction frequency of callus with good quality from wheat anther reached 12.19% in the Institute in 1980. The maximum diffrentiation freguency of anther callus obtained was 50% on C17 medium. C17, medium compositions are as follows (Mg/l): 1400 KNO3, 150 CaCl2-2H2O, 150 MgSO4·7H2O, 300 NH4NO3, 400 KH2PO4, 27.85 FeSO4·7H2O, 37,25 Na2-EDTA, 11.2 MnS04·4H2O, 8.6 ZnSO4·7H2O, 6.2 H3BO3, 0.83 KI, 0.025 CuSO4·5H2O, 0.025 CaCl2·: 6H2O, 8 glycine, 0.5 nicotinic acid, 0.5 thiamine hydrochloride and 1.5 biotin. The re- differentiation medium is supplemented with 2 2,4-D+0.5 KT+7000 agar+90000 sucrose, pH5.8. The dedifferentiation supplemented with 0.5 IBA+2 KT+7000 agar+ 30000 sucrose, pH 5.8.     

Induced Caulogenesis in Long-term Callus Cultures of Rosrnarinus officinalis L

The callus formed in Rosmarinus officinalis L in association with shoot tip proliferation was isolated and subjected to different treatments for good growth. Two basal media, namely, Murashige and Skoog (MS) and Schenk and Hildebrdndt (SH) and their modifications supplemented with 0.25 mg I^-1 6-benzylaminopurine (BAP), 0.5 mg I^-1 indole-3-acetic acid (IAA) and 1.0 mg I^-1 2,4-dichlorophenoxyacetic acid (2,4-D) were used. Callus in MS medium, was compact and remained fresh and green upto 30 days but grew slowly. Whereas, in SH medium callus growth was rapid but it turned brown within 15 days.The browning of callus could be checked with the addition of 1500 mg I^-1 NH,NO, to the medium, in which callus grew 15 fold in fresh weight during 21 days and remained fresh upto 45 days of incubation.The shoot buds differentiated in this somatic callus with the addition of 0.5 mg I^-1 each of BAP, 2-isopentenyl adenine (2ip), IAA and 10 mg I^-1 gibberellic acid (GA₃), within 15 days of incubation provided the callus remained floating on the liquid medium. Histological investigations revealed both peripheral and occasionally internal differentiation of shoot buds. Differentiated shoot buds were proliferated, rooted and transplanted in the soil.     

培养基成分对杜仲愈伤组织生长及次生代谢产物含量的影响

以Bs＋0．5mg／L NAA＋0．5mg／L BA为基本培养基,研究了B5培养基中8种主要无机盐浓度对杜仲愈伤组织生长及绿原酸和总黄酮两种次生代谢产物含量的影响。结果表明：在1000～5000mg／L范围内增加培养基中KNO3的含量有利于愈伤组织生长,B5培养基中当KNO3的浓度达到2／3时,绿原酸和总黄酮含量及产量最高;(NH4)2SO4以4／3原浓度时对愈伤组织生长量、总黄酮含量及产量最高,对绿原酸的含量则是其为原浓度的1／3时最高;MgSO4以2／3浓度对生长量及1／3浓度对绿原酸、总黄酮积累最高;NaH2PO4、CaCl2和MnSO4以原浓度的愈伤组织生长和次生代谢产物合成最好;ZnSO4和FeSO4的原浓度愈伤组织的生长量最大,而1／3浓度的绿原酸和总黄酮含量最高。     

5,6-二氯-吲哚乙酸对烟草愈伤组织衰老的延缓作用

5,6-二氯-吲哚乙酸对革新烟草愈伤组织生长有影响。当愈伤组织在MS_0(对照)和MS 2,4-D培养基上培养22d时,生长停滞,细胞已呈空泡状,正常的超微结构完全破坏,细胞器不复存在,愈伤组织明显褐化。但在MS 5,6-Gl_2-IAA培养基上的愈伤组织仍能正常生长,鲜重和干重下降亦明显延缓,细胞含有原生质内含物,各种细胞器的超微结构仍保持正常。此外,后者的SOD同工酶也明显不同于其它培养基上的愈伤组织,暗示5,6-Gl_2-IAA对烟草愈伤组织衰老的延缓作用可能与SOD同工酶的调节作用有关。     

Somatic embryogenesis and synthetic seed production in Rhinacanthus nasutus (L.) Kurz.

Young healthy cotyledon and leaf explants of Rhinacanthus nasutus (L.) Kurz. were incubated on Murashige and Skoog (MS) medium supplemented with 1.0–5.0 mg/l 2, 4-dichlorophenoxyacetic acid (2,4-D) either alone or in combination with 0.3–1.5 mg/l indole-3-butyric acid (IBA). The optimum callus induction (100 %) was observed from cotyledon explants on MS medium supplemented with 4 mg/l 2, 4-D and 0.5 mg/l IBA. The friable, embryogenic callus when subcultured on half strength MS medium supplemented with IBA (3.0–5.0 mg/l) produced several somatic embryos at various stages of development (globular, heart, torpedo) after 45 days of culture. The highest frequency of callus embryogenesis was observed on ½MS medium supplemented with 4.0 mg/l IBA. Moreover, 47 % of incubated callus responded with a mean number of 16.3 somatic embryos per gram callus. For germination, somatic embryos at the torpedo stage were isolated and subcultured on ½MS medium supplemented with 0.5 mg/l each of 6-benzyladenine and indole-3-acetic acid. After 45 days of culture, plantlets developed with mean lengths of 3.8 cm. Somatic embryos at the torpedo stage were collected and suspended in a matrix of MS medium containing sodium alginate (3 % W/V), dropped into 100 mM calcium chloride (CaCl₂·2H₂O) solution for the production of synthetic seeds. Optimum growth ability of synthetic seed was obtained on MS medium supplemented with 0.2 mg/l gibberellic acid (GA₃). Well developed healthy plantlets derived from somatic embryos and synthetic seeds were hardened and successfully transplanted to soil.