香蕉小茎尖培养和快速繁殖

本文报道14个香蕉品种或品系进行小茎尖离体培养繁殖无病苗。小茎尖培养在改良MS培养基中,附加BA2.0—5.0mg/l,试验结果显示,BA明显促进芽的形成和增殖,随着BA浓度的增高,形成的芽苗数也随着增多。各品种均能诱导丛生芽,但品种间的繁殖率有很大差异。低浓度的Kt或BA有利于诱导生根。培养的试管苗经检验为无病苗。     

罗汉果组织培养中愈伤组织和腋生枝的形成

用罗汉果茎段为外植体,培养在MS+BA1.0+IBA0.1毫克/升培养基上,诱导愈伤组织和芽形成。观察了罗汉果茎段愈伤组织的生长以及腋生枝的形成。罗汉果茎段培养5天后,潜伏腋芽开始萌动和生长。培养10天后罗汉果茎段的基部一端开始膨大。培养20天后产生大量白色疏松的愈伤组织,这时腋生枝已经长成3—6厘米长。培养30天后基部的愈伤组织中有少量瘤状小突起,但再分化形成芽的频率极低。结果表明,罗汉果茎段组培形成的苗均是从腋芽产生的。     

某些因素对玻璃苗形成的影响和玻璃苗在形态解剖上的特点

瑞香试管苗的玻璃化受到细胞分裂素浓度和茎尖外植体大小的影响,细胞分裂素浓度越高,茎尖外植体越小,产生的玻璃苗越多。玻璃苗与正常试管苗的茎尖在形态结构上有明明显差别,主要表现为顶端分生组织原体原套结构异常和细胞的明显液泡化。     

葡萄试管苗热处理结合茎尖培养脱病毒效果的研究

对７个生食葡萄品种的试管苗热处理结合茎尖剥离培养脱除病毒的方法做了研究,结果表明,从热处理试管苗剥离的茎尖培养成活率为６１．２％,其中有１８．１％的成苗。各品种热处理试管苗剥离的茎尖分化再生能力不同：先形成愈伤组织的成苗率较低,而先分化芽的茎尖成苗率较高。这一方法对扇叶病毒和卷叶病毒的脱除率达９２％以上。     

大蒜花序轴离体培养器官发生途径的解剖学研究

以大蒜品种‘三月黄’(Allium sativum L.cv. Sanyuehuang)花序轴为外植体进行离体培养,对其器官发生过程进行了形态学和解剖学观察。结果显示:大蒜花序轴离体培养不经过愈伤组织,通过器官直接发生途径形成不定芽,其不定芽起源于大蒜花序轴维管组织韧皮部一侧周围的皮层薄壁细胞,属于外起源;皮层薄壁细胞经脱分化后,由最先形成的拟分生组织发育为茎尖分生组织,然后环绕其形成叶原基,茎尖和叶共同构成一个完整的不定芽;大蒜花序轴离体培养发生的不定芽与花苞中自然形成的营养芽发生部位一致。不定芽通过壮苗、生根培养可正常生根形成植株,如果继代培养周期超过21 d,鳞茎形成率可达90.56%。     

某些因素对玻璃苗形成的影响和玻璃苗在形态解剖上的特点

瑞香试管苗的玻璃化受到细胞分裂素浓度和茎尖外植体划、的影响,细胞分裂素浓度越高,茎尖外植体越小,产生的玻璃苗越多,玻璃苗与正常试管苗的茎尖在形态结构上有明显差别,主要表现为顶端分生组织原体原套结构异常和细胞的明显液泡化。     

石刁柏花药培养再生植株的生根研究

石刁柏（ＡｓｐａｒａｇｕｓｏｆｆｉｃｉｎａｌｉｓＬ．ｃｖ．ＭａｒｙＷａｓｈｉｎｇｔｏｎ５００）花药来源的试管苗茎尖切段基部根原基的发生和根原基发育形成根是两个不同的阶段。较低浓度的ＮＡＡ（０．０１ｍｇ／Ｌ）和充分的养料供应使茎尖切段基部内源ＡＢＡ持续下降,是切段基部形成愈伤组织并在其中分化出根原基的必要条件;而相对的水分缺乏和进行有效的气体交换则使内源ＡＢＡ迅速上升,促进根原基进一步发育形成根。每个阶段用不同的处理可使生根率达１００％。     

石刁柏花药培养再生植株的生根研究（Ⅱ）

石刁柏花药来源的试管苗茎尖切段基部根原基的发生和根原基发育形成根是两个不同的阶段。较低浓度的ＮＡＡ和充分的养料供应是切段基部愈伤组织形成并在其中分化出根原基的必要条件,而相对的水分缺乏和能进行有效的气体交换则能促进根原基进一步发育形成根。每个阶段应用不同的处理可使生根率达１００％。     

魔芋属植物愈伤组织的诱导和再生植株的研究

用云南魔芋(Amorphophallus yunnanensis)、白魔芋(A.albus)、花魔芋(A.revieri)和勐海魔芋(A.bannaensis)等四个种的叶、鳞叶、花序、匍匐茎、块茎和茎尖为外植体,诱导产生小植物。可通过三种途径获得魔芋再生植株:(1)由外植体诱导愈伤组织,再分化小植株:在添加0.5—1.0mg/1 NAA和BA或KT、ZT的MS培养基上,高频率地诱导瘤状愈伤组织形成,发现NAA对愈伤组织的诱导是必不可少的,而细胞分裂素与之组合,促进瘤状愈伤组织的形成和发育,在无激素或低浓度激素的培养基上,瘤状愈伤组织分化出小植物;(2)茎尖和鳞叶、块茎切块培养,诱导形成多芽苗,产生再生植株;(3)块茎切块诱导产生微型小块茎,然后分化芽和根,长成小植物。本研究为魔芋的快速繁殖提供了新的手段。     

植物组织培养简报摘编

植物名称、外植体 桑树 (亚毋哪‘ba)茎尖和成熟叶片培养基配方(mg/L)(1)MS+6BAI 诱导不定芽(2)1/ZMS 生根成苗 茎尖在(1)上经45天长成高5~6em的无根苗,其主茎下部第一二片接触培养基的叶片表面主脉上分化出不定芽。成熟叶片在(劝土经15天分化出不定芽,每叶片上可分化不定芽20~30个。将带有不定芽的叶片切下转入(1)继续培养,2。夭后成丛生苗。将丛生苗由基部切下于100 ppm工BA溶依或800卫P醉78冬工〔扮但毗吮基)丙醇3溶液中浸债40分钟后,转入(2)份天后生根成苗,生根后15天可进行移栽。 (国内未见报道)作者与单位郑淑湘孔令汉沈永勤(山…     

Cryopreservation of in vitro-cultured multiple bud clusters of asparagus (Asparagus officinalis L. cv Hiroshimagreen (2n=30) by the techniques of vitrification

Summary A culture line of asparagus forming green bulbous structures consisting of numerous multiple bud clusters designated bud clusters was induced from a meristem culture of asparagus (Asparagus officinalis L.cv. Hiroshimagreen, 2n=30). Small cubic segments (2 mm3) cut from bud clusters were cryopreserved using three different cryogenic protocols. Only vitrification produced very high levels of shoot formation after cooling to –196°C. Segments were treated with a vitrification solution (PVS2) at 25°C for 45 min or at 0°C for 120 min prior to a direct plunge into liquid nitrogen. After rapid warming, the segments were expelled into Murashige and Skoog medium containing 1.2 M sucrose for 10 min and then plated on agar shoot outgrowth medium. The average rate of shoot formation of vitrified segments producing normal shoots was near 90% without any preculture and/or cold-acclimation treatment. Revived segments resumed growth within 3 days and developed about three shoots per segment. In vitro-cultured bud clusters appear promising as material for cryopreserving asparagus germplasm.Abbreviations DMSO dimethyl sulfoxide - PVS 2-vitrification solution - LN liquid nitrogen - IBA 3-indolbutyric acid - BA 6-benzylaminopurine - FDA fluorescein diacetate - DSC differential scanning calorimeter     

Histological analysis in shoot organogenesis from hypocotyl explants of<Emphasis Type="Italic"> Kandelia candel</Emphasis> (Rhizophoraceae)

In vitro culture of hypocotyl explants from Kandelia candel, a common mangrove species, on hormone-free Murashige and Skoog (MS) medium resulted in shoot formation. Since the hypocotyls showed good potential for in vitro shoot multiplication, the process of bud primordium formation was analyzed from a histological viewpoint. A wound periderm first appeared at the top, exposed cut surface of the explants. The wound-induced meristem continued to divide giving rise to suberized cells oriented towards the cut surface. After formation of the suberized cell layers, the meristem and its inner derivatives differentiated into multilayered, uniformly packed parenchyma cells. Bud primordia differentiated from the dense cytoplasmic cells of the wound-induced meristem just beneath the suberized layer near the severed vascular bundles. Each explant produced several visible shoot buds. Furthermore, histological sections revealed that additional bud primordia were present within the explant just underneath the suberized cells and that these bud primordia appeared to be arrested in their development. The fact that additional bud primordia were present within the explant suggests that further manipulation of the explant is helpful to maximize the potential of this system.     

腺嘌呤对菠萝快速繁殖的影响

以腺嘌呤（adenine,Ad）作为基本培养基（MS）的添加成分,进行菠萝的快速繁殖。以不加Ad作对照,结果显示不同浓度的Ad分别为1.0、2.0、3.0、4.0、5.0、6.0 mg.L-1对芽的分化及增殖均无显著促进作用。而在壮苗培养中,除Ad为1.0 mg.L-1外,其他各浓度均能极显著地提高幼苗的生长速率,而且在不同浓度间也出现了极显著差异。Ad在3.0～5.0 mg.L-1时,幼苗生长速率最快,可使出苗时间提前30 d以上。     

Efficient plant regeneration from leaves of rapeseed (Brassica napus L.): the influence of AgNO3 and genotype

Factors influencing reliable shoot regeneration from leaf explants of rapeseed (Brassica napus L.) were examined. Addition of AgNO₃ to callus induction medium was significantly effective for shoot regeneration in all three genotypes initially tested. When 48 genotypes subsequently were surveyed, a large variation of shoot regenerability was observed, ranging from 100 to 0% in frequency of bud formation and from 7.5 to 0 in the number of buds per explant. A significant correlation (r=0.84) was observed between the frequency of bud formation and the number of buds per explant. The shoot regenerability from leaf explants was not related to that from cotyledonary explants (r=0.28). Histological observations showed that an organized structure developed from calluses produced at vascular bundle tissues after 7 days of culture on callus induction medium, and they developed shoot apical meristems one week after transfer onto shoot induction medium. Regenerated plantlets were obtained 2 months after the initiation of culture and they normally flowered and set seeds. No alterations of morphology or DNA contents were observed in regenerated plants and their S1 progenies.     

铁核桃离体培养与快速繁殖

以优良单株‘纳雍-1’的单芽茎段为外植体,建立了铁核桃（Juglanssigillata）离体培养与快速繁殖的体系。结果表明,附加6-BA1．0mg·L-1 ＋活·IgK（AC）3．0g·L-1的DKw培养基适宜铁核桃腋芽诱导;适宜铁核桃芽增殖的培养基为DKW＋6-BA1．0mg·L-1 ＋IBA0．02mg·L-1,40d后增殖系数可达7．33;试管苗的茎尖和茎段均可用于增殖培养;一步生根法（低浓度的生长素IBA持续诱导）不利于铁核桃试管苗嫩茎生根;采用二步生根法,生根率最高可达71．73％,其中,不同IBA浓度、暗培养时间、蔗糖浓度和AC含量对试管苗嫩茎生根影响显著,铁核桃试管苗在附]sulBA5,0mg·L-1的1／4DKW培养基中暗培养12d,再转移到不含IBA的1／4DKW培养基（附加AC 3g-L-1和蔗糖20g·L-1）中生根效果最好;生根试管苗采用珍珠岩和营养土两步炼苗,60d后成活率达到87．50％。     

Efficient shoot regeneration from internodal explants of Populus angustifolia, Populus balsamifera and Populus deltoids

In the present study, interactions between the duration of treatment with auxin and different cytokinins and their effect on shoot regeneration were evaluated with the aim to establish a rapid and efficient in vitro regeneration method applicable to a variety of Populus species. Three different species, Populus angustifolia, P. balsamifera, and P. deltoids, were chosen for that purpose. We were successful in regenerating plantlets from stem and petiole explants from all three chosen species using a four-step simple procedure. The first step was callus induction when the explants were exposed to an auxin-rich medium for 0-20 days. During the second step, they were transferred onto a cytokinin-rich medium for shoot bud induction. In the third step, the shoots regenerated were transferred onto a medium with reduced levels of cytokinins to promote shoot proliferation and elongation; finally, in the fourth step, the shoots were rooted and acclimated. A short period (6-10 days) of time of exposure to auxin was sufficient for shoot regeneration. A culture time longer than ten days in callus induction medium drastically reduced the efficiency of shoot regeneration. Besides, cytokinin type and concentration also affected the frequency of shoot induction. A 0.2 mg/l concentration of 2,4-D for callus induction followed by 0.02 mg/l of Thidiazuron for shoot formation proved to be the best treatment for adventitious shoot bud multiplication, generating a maximum of 10-13 shoots of P. balsamifera and P. angustifolia in ten weeks. In contrast, for P. deltoids, a combination of 1.1mg/l 2,4-D, 1.0mg/l NAA, 0.1mg/l zeatin for callus induction followed by a combination of 1mg/l zeatin plus 1.0mg/l BA for shoot bud induction was found to be the most effective, generating on average 15 shoots over a period of ten weeks.     

Regeneration of calabrian pine from juvenile needles

Cytokinins applied in an agar medium induced adventitious buds on cultured needles from seedling of Pinus brutia Ten. Cytokinins applied as pulses to the explants prior to culture were less effective. Irrespective of the mode of cytokinin application, 8 weeks was the time required to bring about bud formation. Organogenetic potential of the cultured needles decreased with chronological age of the explanted seedlings. The induced buds grew into elongated shoots on culture medium without cytokinins, but the inclusion of activated charcoal (1%) doubled the elongation rate. There was an indication that mixtures of cytokinins were more effective than separate cytokinins in producing buds on explants, but the difference between treatments did not achieve statistical significance. Parenchyma cells in mesophyll layers were evidently the target cells responding to the culture conditions. After a period of activity and division in these cells, meristematic zones developed which later led to formation of bud primordia, and subsequently these primordia developed into well-formed adventitious buds. Subsequent rooting (64%) of shoots was achieved using a combination of two auxins and a low level of cytokinin.     

In vitro response of apical bud explants from mature trees of jackfruit (Artocarpus heterophyllus)

A tissue culture technique for rapid vegetative propagation of mature jackfruit trees using apical bud cultures has been developed. Shoot-tip cultures were established on MS medium with 5–10 mm explants dissected from terminal buds of new growth from trunk. After initial culture of bud explants, one- to two-node pieces were taken from the microshoots formed and used to proliferate further axillary shoots for multiplying and maintaining shoot cultures. Benzyladenine and kinetin (4.5–9.0 µM), either separately or together, supported shoot proliferation; higher concentrations of the cytokinins inhibited bud breaking and favoured callus formation at the explant bases. Bud explants taken from emerging trunk sprouts invariably produced clumps of multiple shoots, whereas buds obtained from actively growing top branches generally elongated to form a solitary shoot. November to January was the best season for initiation of cultures from field-grown trees. Shoots proliferated at the initial subcultures had mature morphology and were difficult-to-root. Shoots assumed to be juvenile-like developed at the later passages and could be rooted with 60–80% success using 1/2-MS salts and 10 µM of indolebutyric acid or naphthaleneacetic acid. Regenerated plantlets were transferred to the soil and about 50% survived.