野生南荻与芒杂种多倍体诱导研究

用不同浓度秋水仙素处理野生南荻×芒(Miscanthus lutarioriparia×Miscanthus sinensis)远缘杂交后代以诱导产生多倍体,并对变异株进行形态学和细胞学鉴定,以期获得稳定的四倍体植株并分析其生理特性。结果表明:(1)采用秋水仙素加入培养基处理法和秋水仙素溶液浸泡处理法都可获得一定频率的多倍体植株;胚性愈伤组织以0.2%秋水仙素浸泡处理48h的诱变效果较好,四倍体诱导率达8.7%;芽在0.05%秋水仙素培养基中处理15d较好,四倍体诱导率达10.6%;生根苗在0.1%秋水仙素培养基中处理10d较好,四倍体诱导率达11.1%。(2)经体细胞染色体计数,加倍植株染色体数为2n=4x=76,对照植株的染色体数目为2n=2x=38。(3)生长2年的多倍体植株形态、叶片大小、茎粗、茎壁厚、节间等性状表现出巨大性和超亲优势。     

黄芩组织培养同源四倍体的诱导

应用组织培养技术对黄芩进行多倍体诱导,结果表明：组织培养条件下,在培养基中添加一定浓度和秋水仙素,或者把带有绿色芽点的黄芩愈伤组织经０．２％秋水仙素溶液浸泡一定时间后再进行培养,均可诱发黄芩多倍体的产生,但以后效果较好,诱导率可达４０．０％,通过试管苗根尖染色体显微观察,鉴定出５０多个黄芩同源四倍体,为今后优良品种的选育打下基础。     

秋水仙素诱导七里香多倍体

以不同浓度（0．02％、0．04％、0．08％、0．16％）秋水仙素溶液与二甲基亚砜和丙草胺的体积混合比为2000：10：1的溶液诱导七里香种子萌发苗1-3d的结果表明,所有处理均得到七里香多倍体,其中以秋水仙素浓度为0．08％的混合液处理3d的诱导效果最好,多倍体诱导率迭36．7％。     

扁茎黄芪同源四倍体的诱导

以扁茎黄芪的干燥成熟种子为试验材料,用0．1％、0．3％和0．5％的秋水仙碱溶液分别浸泡种子24h、48h、72h和96h来诱导同源四倍体,并对诱导处理后获得的再生植株进行染色体鉴定,得出以0．3％秋水仙碱溶液浸泡72h为诱导同源四倍体的最佳处理组合。     

普通荞麦植株茎段快速繁殖技术的研究

以普通养麦（Fagopyrum esculentum Moench）植株带节茎段为外植体,用正交设计法研究不同激素处理对荞麦腋芽、丛生芽和根的诱导及分化过程的影响,建立了荞麦离体培养快速繁殖技术。极差分析表明,6-BA是诱导荞麦茎段腋芽和根发育的主要因素,TDZ是诱导丛生芽的关键因素。诱导荞麦茎段腋芽发育的最佳培养基为：MS0＋6-BA1．0mg／L＋NAA0．1mg／L,腋芽诱导率为67．9％。其中,以第二、三节位的腋芽诱导率较高,达80％以上。诱导荞麦茎段丛生芽发育的最佳培养基为：MS0＋6-BA4．0mg／L＋TDZ0．06mg／L,丛芽分化率为166．7％。诱导生根的最佳培养基为：1／2MS0＋6-BA1．0mg／L＋NAA1．0mg／L,生根率为82．8％。该组织培养技术的建立为养麦快速繁殖提供了新途径。     

植物细胞多倍体诱导实验方法的改进

从植物多倍体诱导实验材料处理的方法上,介绍了改进植物多倍体诱导实验的技术,提高了多倍体细胞的分裂指数。实验用0．1％和0．01％浓度的秋水仙素溶液分别处理大蒜根尖24h、36h、48h、72h,进行多倍体诱导,再在清水中分别培养0h、12h、24h、36h,结果表明经清水培养的多倍体细胞分裂指数高于对照：0．01％浓度的秋水仙素处理的多倍体细胞分裂指数高于0．1％多倍体细胞分裂指数。     

秋水仙碱诱导梨离体叶片再生多倍体

以二倍体梨(Pyrus communis L.) 品种'丰产'试管苗的离体叶片为外植体,研究了秋水仙碱处理对叶片不定梢再生及多倍体诱导率的影响.结果表明:(1)随秋水仙碱处理时间增加,叶片不定梢再生率下降,而多倍体诱导率增加;以0.4%的秋水仙碱溶液处理叶片48 h效果最好,多倍体诱导率为6.1%.(2)流式细胞仪(Flow cytometry)分析鉴定表明,获得的多倍体有三倍体、四倍体和混倍体;多倍体与二倍体的形态特征差异明显,多倍体比二倍体茎粗、节间短,叶形指数小,根粗而且短.     

Plectranthus madagascanensis的组织培养及快速繁殖(简报)

以Plectranthus madagascanensis茎段为外植体进行组织培养,建立再生体系。结果表明,在1／2MS＋6-BA0．1mg／L培养基上,芽诱导效果较好,增殖倍数为4．4;1／2MS＋IBA0．5mg／L培养基适宜诱导不定根,诱导率达65％。     

香水白掌的组织培养和快速繁殖

1植物名称白鹤芋属品种香水白掌（Spathiphyllum“Xiangshui”）。2材料类别茎段、茎尖。3培养条件以MS为基本培养基。诱导丛生芽培养基：（1）MS＋6－BA4～6mg·L-1（单位下同）＋NAA0．2。丛生芽增殖培养基：（2）MS＋6－BA2～4＋NAA0．2;（3）培养基（2）＋KH2PO485。4生长与分化情况4．1丛生芽的诱导取香水白掌茎段,剥去外层叶片,75％酒精消毒lmin,然后用灭菌净浸泡20～35min,切取茎尖和茎段,置于培养基（1）上培养。7d后开始出现侧芽萌发和茎尖萌发成苗。30d后将萌发苗基部切割,置于培养基（1）继续培养,2周后出现了…     

中国野生葡萄组织培养研究

对中国野生山葡萄左山—1、左山—2、燕山葡萄燕山—1和秋葡萄平利—7的叶片、叶柄、茎段及单芽茎段进行了离体培养研究。诱导左山—1叶片分化出不定芽的培养基为MS BA 5．0mg／L NAA0．1mg／L,诱导率2．5％;诱导平利—7叶柄分化出不定芽的培养基为MS BA7．0mg／L NAA0．1mg／L,诱导率1．95％;诱导左山—1、燕山—1和平利—7茎段分化出不定芽的培养基与叶柄相同,但诱导率相对较高,分别为8．25％、4．88％和6．49％;应用这一培养基对平利—7、左山—2的单芽茎段进行培养,丛状不定芽的诱导率均为100％。不定芽继代培养基为MS BA0．5mg／L IBA0．2mg／L;生根培养基为1／2MS IBA0．1—0.2mg／L。     

组织培养与秋水仙碱诱导相结合培育植物多倍体的应用(综述)

本文概述组织培养与秋水仙碱诱导相结合培育植物多倍体的优点、诱导方法、最佳药液处理浓度与处理时间组合的选择及诱导材料的选取,并展望其应用前景。     

Cytoskeletal Structures and Oligodendroglial Differentiation in C-6 Glial Cells

Abstract: The relationship of the cytoskeleton to a biochemical expression of oligodendroglial differentiation was studied in cultured C-6 glial cells. Specifically, we investigated the effect of the cytoskeletal perturbants, colchicine and cytochalasin D, on the induction of the oligodendroglial marker enzyme. 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP), caused by removal of serum from the culture medium. Each drug inhibited CNP induction in a concentration-dependent manner, and essentially complete inhibition of induction was observed with 0.25 μ M colchicine or 2.0μ M cytochalasin D. Detailed study of the effect of colchicine was carried out. This antimicrotubular agent not only totally prevented induction if added at the onset of serum removal, but also prevented further induction when added at various times after serum removal. That the effect of colchicine related to the drug's effect on microtubules was supported by the demonstration that lumicolchicine, a colchicine isomer which has no effect on microtubules, had no effect on the CNP induction. Moreover, colchicine, but not lumicolchicine, prevented the morphological signs of differentiation provoked by serum removal. The effect of colchicine was reversible and relatively specific. Thus, no concomitant effect of colchicine on the activity of another plasma membrane enzyme of C-6 cells, i.e., (Na⁺+ K ⁺)-acti-vated ATPase, or on the rate of incorporation of [³H]leucine into total protein of intact cells could be discerned. The possibility that the site of the effect of colchicine is on intracellular events was suggested by the observation that the drug inhibited the induction of CNP by dibutyryl cyclic AMP. The data suggest that the cytoskeleton is involved in oligodendroglial differentiation.     

大花蕙兰四倍体的离体诱导和鉴定

采用组织培养方法研究了秋水仙素处理对大花蕙兰类原球茎增殖、分化和四倍体诱导的效应.结果表明,秋水仙素处理明显抑制类原球茎的增殖和分化,提高类原球茎褐变率和死亡率;在试验浓度和时间范围内,秋水仙素浓度越高,处理时间越长,抑制作用越强,解除抑制作用所需的继代次数越多.所有秋水仙素处理均能诱导出四倍体,但不同处理的四倍体诱导率不同,当处理浓度为0.05%、时间为5 d时,四倍体诱导率最高,为23.7%.二倍体及其四倍体的气孔保卫细胞长度和气孔密度均存在极显著的差异.四倍体植株比二倍体矮,茎部较粗壮,株型紧凑,叶片颜色浓绿、质地变硬.秋水仙素处理和组织培养相结合是创建大花蕙兰多倍体的有效方法.     

Colchicine, an efficient genome-doubling agent for maize (Zea mays L.) microspores cultured in anthero

The construction of maize genotypes with high haploid induction capacity made it possible to study the effect of colchicine on maize androgenesis in vitro. Anther cultures of three hybrids were treated with 0.02% and 0.03% colchicine for 3 days at the beginning of microspore induction. Colchicine added to the induction medium had no negative influence on the androgenic responses (anther induction, induction of structures of microspore origin and their regeneration ability) of the genotypes examined. However, significantly higher fertility was observed in plants originating from colchicine-treated microspores, especially at 0.03%. Cytological examinations showed that colchicine treatment before the first microspore division efficiently arrested mitosis and resulted in homozygous doubled-haploid microspores. Under the experimental conditions, the antimitotic drug had no later effect on the division symmetry of the microspore nucleus, and unequal divisions remained dominant. Callus formation from the induced microspores seemed to be more typical (ranging between 60–70%), but embryo frequency was increased by approximately 10%, especially at the higher colchicine concentration. These results suggest that the mechanism of colchicine action in premitotic maize microspores may differ from that previously observed in wheat. Received: 15 June 1998 / Revision received: 17 September 1998 / Accepted: 3 December 1998     

Manipulation of ploidy for kiwifruit breeding: in vitro chromosome doubling in diploid <Emphasis Type="Italic">Actinidia chinensis</Emphasis> Planch.

Tetraploid plants were induced by colchicine treatment of in vitro leaf petiole segment cultures of five diploid Actinidia chinensis Planch. genotypes, including the commercially important, yellow-fleshed cultivar ‘Hort16A’, three female selections with red-fleshed fruit and one male pollinizer. Petiole segments were incubated on a shoot regeneration medium for a period of 4 weeks, and subsequently microshoots were treated with 0.05 or 0.1% colchicine. About one-third of the regenerated shoots were tetraploid following 0.05% colchicine treatment, more than with 0.1% colchicine treatment. Similar rates of tetraploid induction were achieved with all the genotypes tested. The efficiency of induction of polyploidy depended on the interaction between the types of in vitro culture chosen and the concentration of colchicine used. There are no previous reports of colchicine being used so successfully to induce polyploidy in Actinidia.     

秋水仙素对蚕豆胚根生长的影响及多倍体诱导效应分析

筛选秋水仙素诱导蚕豆胚根多倍体的最适诱导处理组合并分析其诱导效应。以秋水仙素5个浓度(0.025%、0.050%、0.100%、0.150%、0.200%)和4个诱导时间(12、24、48、60h)正交组合(蒸馏水处理为对照)分别处理蚕豆胚根。以根尖诱导率和胚根膨大率的显著性差异确定蚕豆胚根多倍体的最适诱导处理组合,并以胚根细胞染色体数目和幼叶气孔数目的变化对诱导效果进行鉴定,分析其幼苗期的胚根数目和幼苗长度。结果表明:秋水仙素最适诱导时间为48h和浓度为0.100%;气孔数量在诱导时间和诱导浓度之间均有显著差异,但幼苗期的胚根数量和幼苗长度在不同的诱导时间之间无显著差异,诱导浓度之间差异显著。     

Colchicine inhibition of insulin induction of stearoyl-CoA desaturase and fatty acid synthetase in cultured avian liver explants

Chicken embryo liver explants cultured in chemically defined medium in the absence of serum provide a unique system to probe into the mechanism of insulin induction of lipogenic enzymes. Colchicine at concentrations of 0.2 and 1 microM in the culture medium caused inhibition of insulin induction of stearoyl-CoA desaturase and fatty acid synthetase by 50 and 90%, respectively. As measured by immunochemical techniques, the inhibition of the induction of these two enzyme systems resulted from the decreased content of the delta 9-terminal desaturase component of the stearoyl-CoA desaturase and the fatty acid synthetase. Colchicine, however, had no effect on the general protein synthesis, nor did it affect the malic enzyme, which is induced by triiodothyronine but not by insulin. Also, colchicine had no influence on the binding of 125I-insulin to isolated plasma membrane. Pretreatment of liver explants with insulin for 0.5-1 h and subsequent incubation in insulin-free media for 48 h resulted in induction of the desaturase and fatty acid synthetase. However, inclusion of colchicine in the media for 3 h subsequent to the treatment with insulin completely abolished the inductive effect of insulin, suggesting that colchicine affects events occurring subsequent to insulin binding to the cell surface membranes. Since lumicolchicine, an inactive isomer of colchicine, had no effect on insulin action, it is suggested that the inhibition of insulin induction of the desaturase and synthetase is related to the depolymerizing action of colchicine. Therefore, in eliciting long-term responses to insulin, microtubular integrity of the cell may be required for the transfer of a putative from cell surface insulin receptor to intracellular sites.     

Colchicine increases hepatic alkaline phosphatase activity

In vivo administration of colchicine increases the activity of alkaline phosphatase significantly in the livers of rats. Prior treatment with cycloheximide prevented the induction of the enzyme by colchicine suggesting that de novo protein synthesis was essential for the effect of colchicine on alkaline phosphatase activity. Bilateral adrenalectomy did not affect the response of alkaline phosphatase following the administration of colchicine. This indicates that the rise in the level of alkaline phosphatase in liver caused by colchicine is not secondary to the release of glucocorticoids.     

Induction and characterization of tetraploids in poplar

Plant Cell, Tissue and Organ Culture (PCTOC) - Tetraploid poplar plants were induced by colchicine from tissue-cultured shoots; the induction efficiency varied with colchicine concentration....     

Kinetics of micronucleus induction and cytotoxic activity of colchicine in murine erythroblast in vivo.

In previous studies, we inferred some pharmacokinetic and pharmacodynamic parameters of alkylating agents and antimetabolites by comparing their kinetics of micronucleated polychromatic erythrocyte (MN-PCE) induction with the one obtained after the exposure to gamma rays in peripheral blood of mice, assuming that radiation acts immediately because it does not require absorption and distribution in the organism. According to our earlier studies, the kinetics of MN-PCE induction depends mainly on the following: (i) the cytotoxic effects that in turn could affect the duration of cell division; (ii) the pharmacokinetics including the metabolic activation requirement; and (iii) the mechanism of MN induction. The aim of the present study was to analyze the kinetics of MN-PCE induction by an aneuploidogen that induces micronuclei by acting on the achromatic spindle. The kinetics of MN-PCE induction by colchicine, as well as the reduction in the PCE frequency over time was determined in peripheral blood of mice treated with different doses of the aneuploidogen. The genotoxic effect, established as the area beneath the curve (ABC) of MN-PCE versus time-response, indicates an almost directly proportional relationship with respect to dose. Similarly, the relationship between dose and cytotoxic effect determined as the ABC of PCE versus time was inversely proportional, suggesting a relationship between both endpoints and doses administered. However, the number of cells affected by these two phenomena indicates that cytotoxicity is not necessarily caused, or at least not only by genotoxicity. The analysis of the kinetics of MN-PCE induction after the treatment with non-cytotoxic dose of colchicine, indicates that the MN-PCE appear in the blood stream at almost the same time, as occurs after the exposure to gamma rays; in spite of the differences in the cell cycle stage in which they can cause micronucleus (MN). Perhaps the fact that cells are not synchronized does not permit one to observe some difference in the time they appear in the blood. These results suggest that colchicine acts rapidly after exposure. The elimination half-life of colchicine is 17h, suggesting that colchicne is disposable for long time. With high doses of colchicine the pharmacokinetic parameters increases substantially. These data imply that low doses of colchicine are slightly cytotoxic, and that under this circumstances colchicines arrives rapidly to hemopoyetic tissues and acts for several hours.