扶桑插条愈伤组织质膜内陷的超微结构研究

对扶桑插条愈伤组织细胞中质膜内陷现象的超微结构观察结果表明,不同液胞化状态的细胞中均有质膜内陷存在。在分化细胞中,质膜呈波状起伏或形成某些大小不等的质膜内陷。兴胞化细胞中的质膜内陷数量多,体积增大。质膜内陷多呈圆球状,内含多种形状的内含物,由靠近原质体,线粒体和高尔基体的质膜组成。     

温度对马尾松组培单芽不定根发生的影响

马尾松( Pinus massoniana)组织培养生根困难,该研究在严格控制光温条件的光照培养中,以马尾松无性系组培继代芽为材料,分析了在不同温度处理下马尾松组培单芽生根率、生根时间、根系条数和移栽成活率等生根能力指标以及生根解剖构造的变化。所有数据均采用SPSS 19.0统计分析软件,进行单因素分析(ANOVA)的显著性检验及最小显著性差异法(LSD)的多重比较。结果表明：在25℃最适温度培养下,马尾松组培生根效果较佳,移栽成活率最高,可达98.1％。低温处理下,生根时间显著延长,根系条数减少,生根率偏低;高温处理下,根茎愈伤组织明显,移栽成活率显著降低。从生根解剖构造来看,马尾松不定根主要由维管形成层细胞分化而成。与25℃适温处理相比较,在20℃较低温处理下,细胞分裂活动缓慢,不定根原始体诱发较少;而在30℃较高温处理下,细胞活动旺盛,但髓射线与维管组织细胞染色颜色加深、排列紧密,将诱发的不定根原基细胞团区隔成带状或片状。该研究结果探讨了培养环境温度对马尾松组培单芽生根能力的影响,为马尾松组培苗生产提供了参考。     

九种生根剂对绒毛皂荚嫩枝扦插生根的影响

绒毛皂荚(Gleditsia vestita Chun et How ex B.G.Li)为豆科落叶乔木,是国家三级保护植物。目前我国仅湖南省南岳广济寺有2株大母树,结果极少,难以扩大繁殖。为挽救这一物种,1991年6月进行了扦插试验。     

芒果子叶切段不定根形成的影响因素分析

分别用不同成熟时间、不同取材部位、不同品种、不同大小的芒果子叶切段为外植体进行不定根的诱导,以探讨影响芒果子叶切段不定根形成能力的原因.结果表明,芒果子叶切段的生根能力随着芒果成熟度的增加而逐渐提高,花后50和60 d的2.0 cm长子叶切段都无不定根形成,从花后70 d开始有不定根形成,此时生根率为28.6%,之后其生根能力迅速提高,在花后90 d生根率达到76.7%,之后生根率稳定保持直到110 d果实成熟.成熟芒果的子叶切段长度(2.0、1.0、0.5和0.2 cm)对不定根的形成有显著影响,0.2 cm的子叶切段上无不定根形成,另外3个长度的切段都有不定根形成,且生根能力随着长度的增大而逐渐提高.取材位置(靠近或远离胚轴)则对生根影响不大,且紫花芒、红芒、青皮芒等几种常见芒果品种的不定根形成能力基本相同.     

IBA对野生蔬菜少花龙葵插条生根的影响

在室内水培条件下, 研究了吲哚丁酸(IBA)、插条类型及插条留叶方式对野生蔬菜少花龙葵(Solanum photeinocarpum)插条生根的影响。结果表明, 5～35 mg L-1 IBA处理的少花龙葵半叶嫩枝插条生根率均为100%, 以20 mg L-1 IBA处理的平均生根数最多。促进少花龙葵半叶硬枝插条生根的IBA浓度为15～35 mg L-1,其中以25 mg L-1 IBA的效果最好。少花龙葵嫩枝和硬枝插条分别在20与25 mg L-1 IBA处理下,均以半叶插条的生根效果最好、缺叶插条的生根效果最差,全叶插条的生根效果居中。     

黄腐酸对葡萄插条生根的影响（简报）

用0、100、200、400、800mg／L黄腐酸溶液浸泡巨峰而萄插条12h后催粮月余,其生根数、根长和芽的生长量都有增加。对穿的影响比根小,因而根／冠比值增加。     

柃木插条生根的解剖学研究

采用石蜡切片法对柃木（Eurya japonica Thunb．）插条不定根的形成进行了解剖学研究。观察结果表明,柃木插条不定根原始体为诱生根原始体;不定根原基起源于维管形成层与髓射线的交叉区域。插条的韧皮部存在较连续的排列成环状的厚壁纤维细胞,茎内无生根原基。柃木插条的这些结构特征可能与柃木插条生根率低有关。     

布洛芬对菊花插条生根、菊苗质量的影响

研究了布洛芬对菊花插条生根、茎叶生长和菊苗质量的影响。结果表明,将菊花插条束蘸1000mg.L^-1布洛芬液5g然后扦插,能有效地促进菊花插条生根,显著增加平均每插条的生根数、最长根长度和根干重;并能促进菊苗生长,增加茎叶鲜重;菊苗的质量明显提高。     

蕨藻红素促进大豆插条不定根的形成

对蕨藻红素影响大豆下胚轴插条不定根形成的研究表明：蕨藻红素促进大豆插条不定根的形成,其最适浓度为0.5μmol·L^-1,最适处理时间为2d。0.5μmol·L^-1蕨藻红素处理大豆插条后,不定根诱导阶段（0～24h）的POD、CAT、IAAox活性较低;而不定根形成生长阶段（24～72h）的CAT和IAAox活性较高,POD活性低于未作处理的。试验推测蕨藻红素促进大豆插条不定根形成的生理基础可能与其影响POD、CAT和IAAox活性有关。     

Protein Electrophoresis of Single Pollen Grains of Hibiscus rosa-sinensis

Electrophoresis and staining of proteins from the single pollen grains of Hibiscus rosasinensis have been developed by using general ultrathin polyacrylamide gel combined with highly-sensitive silver staining technique. The result revealed that the pollen abortion could occur in different stages of pollen development. The protein patterns varied greatly in different stages of pollen development, even in the different pollen grains in the same anther at the same development stage. Some bands exhibited a disjunction by classical Mendelian ratio 1: 1, suggesting that the gene loci were heterogeneous and the proteins were related to the expression of the genes at the early stage of pollen development.     

响应面法优化扶桑叶黄酮超声提取工艺

以扶桑叶为研究材料,以Box-Behnken中心组合实验设计,利用响应面法对扶桑叶黄酮提取工艺进行优化。结果表明,超声波辅助乙醇提取扶桑叶黄酮优化工艺条件为乙醇浓度70%,超声提取时间70 min,液料比40∶1。在最佳工艺条件下扶桑叶黄酮提取的得率最高,为34.56 mg/g。     

In vitro adventitious root induction in Antirrhinum majus L.

A broadly applicable method for the successful induction of root systems in a number of cultivars of A. majus has been determined. This involves a double filter-paper bridge with a liquid medium for root induction and allows the transfer of culture-grown plantlets to a glasshouse environment with minimal disturbance to the plant as a whole. 100% survival of transferred plantlets has been achieved with the inclusion of a few simple precautions upon shoot transfer and during the initial stages of plant establishment in vivo.     

美国黄松组织培养不定根诱导的研究

以GD、SH和1／2SH基本培养基对美国黄松不定芽进行不定根的诱导。试验结果表明基本培养基的种类对不定芽形成不定根起主要作用。在1／2SH培养基上附加0．5mg／L的NAA不定根的诱导率为3．3％。试验首次在离体培养条件下,以美国黄松种胚为外植体获得了再生小植株。     

不同密度棉花粉蚧种群对扶桑生长的影响

棉花粉蚧Phenacoccus solenopsis Tinsley是我国一种重要外来入侵害虫.关于该害虫入侵发生对作物的危害程度一直是关注的重要方面.本文通过定量接种虫量的方法,研究了棉花粉蚧初孵若虫不同初始密度(50头/株、100头/株、200头/株、400头/株、800头/株)下扶桑苗生长规律.结果植株生长表明,...     

离体黄瓜子叶不定根发生的研究

离体黄瓜子叶在仅加有双蒸水的培养皿中能高频率发生不定根的现象,并对不定根发生过程中过氧化物酶（ＰＯＤ）活性、可溶性蛋白和核酸含量的变化进行了测定。：６ｄ苗子叶不定根发生率最高,不定根发生高峰是在培养后３ｄ～５ｄ,在不定根发生过程中,过氧化物酶生呈上升趋势,可溶性蛋白和核酸含蜈则降低。     

Effect of mitotic inhibitors on the ultrastructure of root meristem cells

After 5 h in 10^-3M vinblastine the most obvious effects upon Vicia faba L. cells are seen in the spindle apparatus. These include the microtubules themselves as indicated by c-type metaphases and the pole regions of otherwise intact spindles, leading to multipolar anaphases and to telophases with more than two daughter nuclei. Vesicle transport may be undisturbed and new cell walls can be formed, although cases of disturbed cell plate and cell wall formation were noted occasionally, accompanied by myelinizations in phragmosomes. After 24 h in the same concentration of vinblastine, divisions are no longer observed and the plasma membranes are severely affected. They show extensive myelinizations, accumulations of lipids and dehiscence from the cell walls which are frequently thickened and irregularly formed. Of the other cellular membranes, the nuclear envelope and, more frequently, the tonoplast may be affected. Electron-dense deposits appear in the vacuoles. Comparable, though less severe, changes including multipolar anaphases and myelinizations result from treatment with lumicolchicine, but not with colchicine. Vinblastine leads to the appearance of filament bundles both in cytoplasm and karyoplasm, lumicolchicine to morphologically identical filaments in the cytoplasm alone. The nature of these filaments is unknown.Abbreviation VLB vincaleukoblastine     

Effect of polyamines on adventitious root formation from Tobacco (Nicotiana tabaccum) leaf segments

To elucidate the effect of polyamines on adventitious root formation, we investigated the relationship between the frequency of adventitious root formation and the endogenous content of free polyamines in tobacco leaf segments which had been treated with polyamine biosynthesis inhibitors and polyamines. Adventitious root formation was inhibited in rooting medium (10 μM IAA) with methylglyoxal-bis(guanylhydrazone) (MGBG) or cyclohexylamine (CHA), and promoted with spermidine and putrescine. Treatment with high IAA (100 μM) medium plus CHA or MGBG promoted rooting up reversion of the rooting inhibition than the one treated with high IAA concentration alone. Spermidine promoted adventitious root numbers on low IAA (1 μM) medium when applied during culture period. The rooting inductive phase (in the presence of IAA) was determined by periodical transfer of leaf segments from IAA-containing medium to IAA free medium, and by changing polyamine contents, to be inductive phase. Putrescine and spermidine were accumulated to a maximum during the inductive phase. Therefore, the results point out the involvement of polyamines in inductive phase of adventitious root formation in tobacco leaf segments.     

Influence of ethylene on adventitious root formation in mung bean hypocotyl cuttings

The relationship between ethylene and adventitious root formation in mung bean hypocotyl cuttings was studied.Ethephon, an ethylene-releasing compound, at 5 x 10 -5 M increased root number and root dry weight on hypo-cotyl cuttings. When ethephon was applied to hypocotyl at different times after excision, there were two effectivetimes for root production i.e. between 06 h and 18-24 h. These two time periods correspond to the induction phase and the late initiation phase of root development, respectively. After excision, three peaks of ethylene productionwere observed. The first peak commencing at 6 h started the sequence of reactions leading root formation, the second peak appearing at 12 h coincided with the beginning of the increase of the IAA level during primordia initiation, and the third peak showing at 48 h played a role in root differentiation and growth. Ethylene stimulated rooting by enhancing the increase in auxins. Thus it appears that the IAA-induced ethylene production may be a factor involved in the stimulation of adventitious root formation.     

不定根发生分子调控机制的研究进展

不定根发生问题,既是植物无性繁殖和工厂化育苗实践的核心问题,又是植物发育和形态建成等方面的重要理论问题。由于不定根发生过程的复杂性,到目前为止对其调控机制的了解还十分有限。大量研究证实,不定根发生与植物生长素类物质密切相关,因此现有的研究不仅围绕生长素及其信号传导途径展开,而且还涉及到基因表观遗传学调控水平。目前已经鉴定出一些与不定根发生相关的生长素信号传导因子,如NO、cGMP、microRNAs等。同时,还克隆到一些与不定根发生相关的基因,如OsPIN1、OsCKI1、NPK1、ARL1等。此外,发现DNA甲基化可以抑制DNA与蛋白(MeCP2) 的结合,从而抑制基因转录;microRNA可以使基因沉默来调控不定根的发生状况。本文围绕不定根发生的激素调控、不定根发生的基因调控、不定根发生的生长素信号传导机制、表观遗传调控等几个方面综述了近年来的研究进展。