苹果矮化砧木‘JM7’的组织培养及其离体叶片不定梢再生

以苹果优良矮化砧木‘JM7’ （Malus prunifolia×M. pumila ‘Malling 9’）为试材, 研究了基本培养基对试管苗增殖生长的影响、蔗糖浓度对试管苗生根的影响及基本培养基、细胞分裂素种类和浓度对离体叶片不定梢再生的影响。结果表明： 基本培养基MS比QL显著提高增殖梢数, 但QL比MS更有利于获得健壮生长的绿苗。3%蔗糖浓度比2%的不定根发生速度快。叶片不定梢再生最适宜的基本培养基是QL。在QL培养基上, 6-BA和TDZ对离体叶片不定梢再生率的影响无显著差异, 但6-BA诱导产生的不定芽在不定梢诱导培养基上可直接伸长生长形成不定梢, 而TDZ诱导产生的不定芽需转移到不加TDZ而加低浓度6-BA的培养基上形成伸长生长的不定梢。     

泰山酸枣离体叶片再生体系的建立

以泰山酸枣叶片为外植体,以WPM为基本培养基,研究了植物生长调节剂种类、浓度及培养方法等因素对离体叶片不定芽再生的影响,结果表明:不定芽启动的最佳培养基激素组合为1.0 mg·L-1 TDZ+0.5 mg·L-1 IAA;不定芽诱导伸长最佳培养基的激素组合为0.1 mg·L-1 IAA+0.5 mg·L-1 GA3.暗培养是不定芽再生的必需条件,在最适宜的不定芽再生培养基上,叶片连续光培养,不定芽不能再生;叶片先进行暗培养3周后转入光下培养,叶片不定芽再生效果最好,再生率最高可达100%.     

TDZ高效诱导蝴蝶兰叶片不定芽及植株再生

以蝴蝶兰（Phalaenopsis）无菌幼苗叶片为材料,研究添加TDZ（噻重氮苯基脲）条件下不同基因型、激素组合、叶片大小、暗培养时间对不定芽发生和再生植株的影响。结果表明：在相同培养条件下,不同基因型外植体芽诱导率差异显著,‘红天使’最高,达81.5%,‘汕农姑娘’等2个品种为0,‘满天红’等4个品种为9.2%～34.9%;添加TDZ芽诱导率显著高于6-BA;单独添加TDZ或6-BA芽诱导率显著高于NAA与TDZ或6-BA的组合。叶片越小不定芽诱导率越高;短时间暗处理有利于不定芽的发生。以1～2 cm长叶片为材料、15 d暗处理、在1/2 MS添加3 mg/L TDZ培养基中,‘红天使’的叶片外植体芽诱导率和平均不定芽数分别可达100.0%和18.2个。研究发现,在继代培养中TDZ对芽的伸长有抑制作用。     

枣树离体叶片不定芽再生体系建立的研究

建立了木枣无菌试管苗快繁体系,以无菌苗叶片为外植体,对影响离体叶片不定芽直接再生的因素进行了研究.试验结果表明,TDZ比BA能更有效地诱导叶片不定芽的再生;褐化是抑制不定芽再生频率提高的关键因子,培养基中添加PVP、V c及改变生长素的种类和浓度均不能促进不定芽再生;添加A gNO3能够减轻褐化并可以大幅度提高再生频率,同时培养初期经过3周避光培养更有利于提高再生效率.因此,以附加2.0 m g/L TDZ和0.2 m g/L IBA的M S培养基,并添加5.0 m g/L A gNO3,可以高效诱导木枣离体叶片不定芽再生,再生频率最高达98.3%.不定芽在附加0.2 m g/L IBA和0.5 m g/L GA3的M S培养基上进行继代伸长培养,当不定芽长至3 cm时,转接至附加0.4 m g/L IBA的1/2 M S培养基上可以良好地诱导生根.     

香石竹叶片离体再生体系的建立

以香石竹(Dianthus caryophyllus Linn.)无菌苗叶片为外植体,从不同细胞分裂素及其他激素配合使用等方面进行筛选,建立香石竹叶片离体再生体系.结果表明,不同的细胞分裂素影响叶片不定芽分化频率,其中较低浓度的6-BA(0.5 mg·L-1)和TDZ(0.001 mg·L-1)配合使用能有效诱导香石竹叶片不定芽分化;添加一定浓度的PP333(4 mg·L-1)可提高叶片不定芽分化频率和平均芽数.香石竹叶片不定芽分化的适宜培养基为:MS 0.002mg·L-1TDZ 0.5 mg·L-16-BA 0.2 mg·L-1IAA 4 mg·L-1PP333;壮苗培养基为:MS 0.2 mg·L-1 6-BA 0.2 mg·L-1IAA;生根培养基为:1/2 MS.不定芽诱导频率达到42.61%,平均芽数为4.53个.     

植物生长调节剂对白头翁叶片培养的影响

以白头翁试管苗叶片为外植体,以MS为基础培养基,探讨不同细胞分裂素和生长素对叶片不定芽诱导、愈伤组织的诱导、增殖、再分化的影响。实验结果表明：细胞分裂素TDZ适合于白头翁叶片培养,与生长素搭配使用使叶片发生分化;2,4-D对愈伤组织的诱导能力相对较强。叶片直接诱导不定芽的激素组合为TDZ0．3mg／L＋NAA0．1mg／L;愈伤组织增殖的激素组合为TDZ0．2mg／L＋2,4-D0．2mg／L,将愈伤组织转接到TDZ和NAA组合的培养基上时会再分化。     

马兜铃不含腋芽茎段不定芽的诱导

为建立马兜铃(Aristolochia debilis Sieb.et Zucc)不含腋芽茎段的不定芽诱导体系,采用正交设计方法研究植物生长调节剂、预培养方式和AgNO3对不定芽诱导的影响。结果表明:植物生长调节物质对不定芽诱导的影响以TDZ6-BAIAA,其中TDZ的影响极显著(P0.01),6-BA的影响显著(P0.05)。不定芽诱导的最适培养基为MS+0.5 mg L–1 TDZ+0.1 mg L–1IAA+0.5 mg L–1 6-BA+2 mg L–1 AgNO3+3%蔗糖+0.6%琼脂(pH 5.8);预培养方式为在MS+0.1 mg L–1 2,4-D+3%蔗糖+0.6%琼脂培养基上暗培养2 d。马兜铃不含腋芽茎段的不定芽诱导率最高可达37.5%。     

细胞分裂素种类及添加量对蓝浆果叶片离体再生的影响

以南方高丛蓝浆果(Vaccinium corymbosum hybrids)品种‘南月’(‘Southmoon’)优选系A18和兔眼蓝浆果(V.ashei Reade)品种‘灿烂’(‘Brightwell’)离体叶片为外植体,研究了培养基中添加不同浓度TDZ(0.5、1.0和2.0mg·L-1)、CPPU(2.0、4.0和8.0 mg·L-1)、ZT(2.0、4.0和8.0 mg·L-1)和2iP(4.0、8.0和16.0 mg·L-1)对叶片不定芽再生的影响.结果表明:在培养基中添加TDZ和CPPU对叶片不定芽的诱导效果优于ZT和2iP,再生率有显著差异(P＜0.05).TDZ诱导不定芽出现所需的时间最短且再生率最高,不定芽密集并呈深绿色;其中,在添加0.5 ～2.0 mg·L-1TDZ的培养基上,A18叶片再生率均为100.00％,‘灿烂’叶片再生率最高达79.17％.CPPU也有较强的诱导能力但不定芽出现所需的时间推迟3～5d,且不定芽的密集程度也有所降低;其中,在添加2.0～8.0 mg·L-1CPPU的培养基上,A18叶片再生率为100.00％～93.75％;而‘灿烂’叶片再生率随CPPU质量浓度提高呈下降趋势(72.91％ ～47.91％).ZT和2iP诱导能力差,在添加不同质量浓度ZT和2iP的培养基上A18和‘灿烂’叶片再生率均为0.00％.此外,A18和‘灿烂’的再生能力有差异,在相同条件下A18叶片的再生能力优于‘灿烂’叶片.研究结果显示:基因型以及培养基中细胞分裂素的种类和添加量是影响不同品种蓝浆果叶片不定芽再生的主要因素.     

草莓高效离体叶片再生体系的建立

以草莓'明宝(Meiho)'和'红颊(Benihope)'的叶片为外植体,研究了不同基本培养基、暗培养时间、植物生长调节剂、叶龄、不同放置方式对其不定芽再生的影响.结果表明:各品种叶片不定芽离体再生的最佳条件不同.'明宝'叶片的最佳不定芽再生培养基为MS+2.5 mg/L TDZ+0.1 mg/L IBA+0.1 mg/L 2,4-D,叶片再生的最佳叶龄为30～40 d,再生率可达82.8%;'红颊'叶片的最佳不定芽再生培养基为MS+2.0 mg/L TDZ+0.1 mg/L IBA+0.1 mg/L 2,4-D,叶片再生的最佳叶龄在10～20 d,再生率可达79.8%.2个品种叶片暗培养14 d可以提高不定芽再生率;叶片正放比反放再生效果好;添加8 mg/L AgNO3和1 000 mg/L活性炭可有效提高再生率.     

白皮松成熟胚的离体培养研究

以白皮松成熟胚为外植体诱导再生小植株.试验结果表明,成熟胚不定芽诱导以MS培养基最佳,附加0.294 mg/L的NAA和3.56 mg/L的6-BA时,诱导率接近100%;MS培养基附加NAA(0.05 mg/L)时,平均增殖系数可达6.3以上.不定芽增殖率最大值(10)出现在SH培养基上,此时NAA浓度为0.05 mg/L、6-BA浓度为4 mg/L.MS培养基中加入适量活性炭和GA3能促进不定芽生长,随着活性炭和GA3浓度的增加,有效嫩梢(≥2cm和≥4 cm)的比率显著增高;当活性炭和GA3浓度过高时(分别超过2.75 g/L和4.1 mg/L),不定芽的伸长与生长受到抑制.在离体培养条件下,以种胚为外植体获得了无根苗.     

二花蝴蝶草的组织培养及植株再生

二花蝴蝶草(Torenia biniflora)为玄参科蝴蝶草属一年生植物,分布于广东、广西等亚热带地区,是一种观赏性较高的野生花卉。在自然生长条件下,二花蝴蝶草繁殖速度慢、增殖率低,而且花色和花型种类偏少,无法满足市场多样化的要求。植物组织培养技术为观赏植物的品种改良和新品种选育提供了新途径,目前蓝猪耳、蔓性蝴蝶草和单色蝴蝶草等蝴蝶草属植物的组织培养已获得成功,但二花蝴蝶草的组织培养尚未见有相关报道。该研究以二花蝴蝶草全展叶片为外植体,研究了培养基中添加不同种类和浓度植物生长物质对不定芽诱导和生长的影响,以及离子强度和不同浓度IBA对生根的影响。根据不定芽的诱导率和平均芽数筛选出最佳不定芽诱导培养基,并从生根率、平均根数和平均根长等方面筛选出最佳生根培养基。结果表明:不定芽诱导与植物生长物质的浓度和种类有关,以MS+6-BA 0.5 mg·L-1+NAA 0.2 mg·L-1培养基的诱导效果最佳;二花蝴蝶草生根的最佳基本培养基为1/2MS,不同浓度的IBA对二花蝴蝶草的生根影响也不相同,其中以IBA(0.05 mg·L-1)诱导不定芽的生根效果最佳。该研究建立了二花蝴蝶草的高频离体再生体系,为二花蝴蝶草的快速繁殖和遗传转化研究奠定了基础。     

小麦根愈伤组织胚胎发育过程研究

实验通过对６个人工合成小麦品系和对照品种“中国春”种子根愈伤组织分化形成再生植株的过程进行形态和组织切片观察,发现分化初期有２种途径,一种是从愈伤组织先形成不定胚,然后再发育成不定芽和不定根,另一种途径是直接从愈伤组织中分化发育成不定根和不定芽;分化后期不定芽和不定根生长发育有３种类型：一种是不定芽发育先于不定根,一种是不定芽与不定期不定芽和不定根生长发育有种类型：一种是不一定芽发育先于不定根,一     

Rapid plant regeneration from various explants of Jatropha integerrima

A simple, rapid and reproducible protocol for direct shoot regeneration from different explants of Jatropha integerrima was developed. Prolific adventitious shoot bud initiation was obtained using a combination of 2.2 or 4.4 M benzyladenine and 4.9 M indole-3-butyric acid (IBA). Reduction of IBA concentration (2.5 M) promoted further development of shoots. Regenerated shoots rooted readily on Murashige and Skoog (MS) medium lacking growth regulators. Plantlets were acclimatized and successfully transferred to pots.     

In vitro initiation of adventitious structures in relation to the abscission zone in needle explants of Picea abies: anatomical considerations

A comparison of the regeneration potential of needles of different ages in Picea abies emphasized the importance of taking into account the manner of explantation as well as the state of differentiation of the abscission zone. Generally, response in terms of initiation of adventitious structures decreased progressively not only with needle age (5 to 10 to 15 mm long) but also with the distance from the abscission zone towards the tip, that is, distally. On a bud-induction medium adventitious shoot but primordia were produced proximally and distally (except for the very tip) of the weakly-developed abscission zone in needles ca. 5 mm and shorter. In needles between 5 and 10 mm long the various cell types of the abscission zone commenced differentiation, and adventitious structures (shoot bud and other primordia) were formed proximal and immediately distal to it. In needles ca. 15 mm long, in which the abscission zone's hyaline, separation and protective layers became well-developed and where senescence of the distal part commenced, response was limited to proximal tissues. Divisions giving rise to adventitious primordia distal to the abscission zone arose from epidermal cells proper and, in a more acropetal position, also from subsidiary cells of the stomata. Cells of the hypodermis contributed only in the near-distal region of the abscission zone in younger needles, and before commencing differentiation into fibres.
When excised carefully, the explant consists of a leaf plus a peg-like cushion of axillary, meristematic tissue proximal to the abscission zone and capable of ready regeneration. In view of the apparent relationship between age and the stage of development of the abscission zone, it was concluded that there exists a critical needle length which should not be exceeded when attempting in vitro induction of organ primordia.     

Promotion of root emergence in vitro from rhizome buds of Lapageria rosea cv. Nashcourt after proliferation in the presence of paclobutrazol

Medium components that may influence the emergence of adventitious root primordia in rhizome buds of Lapageria rosea (Ruiz et Pav.) cv. Nashcourt in vitro were examined. Sucrose was the only medium component tested that affected root emergence. Increasing the sucrose concentration in the medium from 10 to 30 g 1^-1 stimulated adventitious root emergence from rhizome buds that had been proliferated on a medium containing the gibberellin biosynthesis inhibitor paclobutrazol (5 M). Successful clonal propagation of L. rosea cv. Nashcourt can now be achieved by a rhizome bud proliferation stage(s) in the presence of paclobutrazol followed by an adventitious root emergence stage in the absence of paclobutrazol.     

Effect of genotype on rooting of hypocotyls and in vitro-produced shoots of Pinus radiata

Significant genotypic variation at both the family and clone-within-family levels was seen for hypocotyl rooting and the rooting of adventitious shoots produced in vitro for Pinus radiata D. Don. High rooting frequencies for hypocotyls were obtained in the absence of exogenous auxin; auxin greatly stimulated the rooting of adventitious shoots. No correlation was seen between the rooting of hypocotyls and shoots; families whose hypocotyls rooted at high frequencies did not necessarily produce shoots that rooted at high frequency. No correlation was seen between adventitious shoot production and subsequent rooting at either the family or clone level. The lack of a negative correlation indicated that selecting families or clones for high levels of shoot production will not automatically select for low rooting ability, obviating a possible bottleneck for commercial propagation of Pinus radiata. Significant family by replication interaction suggests that rooting protocols could be optimized through manipulations of the rooting environment for each family.     

Factors affecting shoot initiation from tuber discs of potato (Solanum tuberosum)

Discs of cortical and perimedullary tissue from tubers of potato (Solanum tuberosum L. cv. Superior) formed adventitious shoots when cultured on a medium containing Murashige and Skoog's salts, myo-inositol, 100 mg/l; folic acid, 0.5 mg/l; D-biotin, 0.05 mg/l; gibberellic acid (GA₃), 0.5 mg/l; thiamine ˙ HCl, 0.1 mg/l; glycine, 2.0 mg/l; pyridoxine ˙ HCl, 0.5 mg/l; nicotinic acid, 0.5 mg/l; sucrose, 25 g/l; casein hydrolysate, 1 g/l; Bacto agar, 9.0 g/l; and a cytokinin [N⁶-benzylaminopurine (BAP), N⁶-γ,γ-dimethylallylaminopurine (2iP), or N⁶-furfurylaminopurine (kinetin)]. Discs of pith tissue either failed to survive or produced callus but did not undergo morphogenesis. Cytokinin was essential for explant survival, while BAP at 3.0 mg/l was most efficacious in promoting shoot initiation. Auxin was not essential for shoot initiation or development; however, a low concentration (0.03 mg/l) of α-naphthaleneacetic acid (NAA) stimulated both explant survival and the number of shoots produced per disc. Indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA) did not stimulate shoot initiation. GA₃ was essential for both shoot initiation and subsequent shoot development. The highest incidence of morphogenesis (over 100 shoots in 12 weeks) occurred from tuber discs cultured at 18°C constant and under a photon flux density of 60 μE m^-2s^-1. No difference in regenerative ability was found in explants taken from source tubers stored for 0 to 20 weeks at 4°C. A histological examination indicated that shoots developed from small clusters of meristematic cells which were initiated from within small protuberances on the surface of the tuber disc 3 weeks after transfer.     

In vitro organogenesis of elephant apple (Feronia limonia)

Elephant apple (Feronia limonia L.). was micropropagated on MS medium containing 4.4 M benzyladenine and 4.6 M kinetin using cotyledon explants taken from in vitro-grown seedlings. Adventitious buds formed on the cotyledon developed into shoots that were rooted in half-strength MS medium containing 0.57 M indoleacetic acid and 0.49 M indolebutyric acid. Plants were successfully established in soil.Abbreviations BA 6-benzyladenine - IAA 3-indoleacetic acid - IBA 3-indolebutyric acid - MS Murashige & Skoog     

Organogenesis and somatic embryogenesis in callus cultures ofRosa hybrida andRosa chinensis minima

Pre-incubation of somatic tissues of the cut rose Carefree Beauty and miniature roses Red Sunblaze and Baby Katie in 10, 100, or 200 M 2,4-D induced the development of highly rhizogenic callus. Upon transfer of rhizogenic callus to a regeneration medium containing 23 M TDZ and 3 M GA₃, a low frequency of shoot organogenesis (3.3%) and somatic embryogenesis (6.6%) was observed. Incubation of leaf and stem internodes in 11, 27, 54, 81, or 108 M NAA followed by transfer of explants to the regeneration medium resulted in up to a 25% increase in shoot organogenesis from callus-derived internodal explants of Red Sunblaze, but no somatic embryogenesis was observed. The influence of glucose versus sucrose in the regeneration medium on leaf explants of Carefree Beauty and Baby Katie pre-incubated in 100 M 2,4-D revealed a difference in genotypic response to shoot organogenesis and somatic embryogenesis. For Carefree Beauty, a concentration of 111 mM glucose induced higher frequencies of both organogenic (33%) and embryogenic calluses (25%) than either 59 mM or 117 mM sucrose. For Baby Katie, no significant difference was found for number of organogenic calluses induced on 59 mM sucrose and 111 mM glucose.Abbreviations ABA Abscisic acid - BA Benzyladenine - 2,4-D 2,4-Dichlorophenoxyacetic acid - GA₃ Gibberellic acid - IAA Indoleacetic acid - MS Murashige & Skoog (1962) - NAA -Naphthaleneacetic acid - TDZ Thidiazuron     

Shoot organogenesis and plant regeneration in mulberry (Morus bombycis Koidz): Factors influencing morphogenetic potential in callus cultures

Regeneration of multiple shoots via callus induction and organogenesis was achieved in mulberry (Morus bombycis). Pre-soaked internodal explants in 4.4–8.9 M benzyladenine (BA) formed callus on Linsmaier and Skoog's medium containing 2,4-dichlorophenoxyacetic acid (9.05 M), -naphthaleneacetic acid (2.85 M) and BA (2.2 M). Explants soaked for 48 to 72 h in low levels of BA produced loose and nodular callus that showed regeneration ability. Calluses developed adventitious shoot buds within 3–4 weeks on medium containing BA (8.9 M). Fifteen-week-old calluses developed fewer shoot buds than five-week-old calluses, indicating a decrease in morphogenetic potential with increasing duration of callus cultures. Semi-thin section microscopy was used to evaluate incapability of sustained regeneration. Development of normal shoot bud primordia, due to sub-surface reorganisation, was high in young calluses. The decline in the frequency of shoot bud primordia formation with callus ageing is due to reduced cell division activity in epidermal as well as sub-epidermal layers.