根尖维管组织在狗蔷薇类原球茎发生中的作用

为了解狗蔷薇(Rosa canina L.)类原球茎发生机制,以建立月季高效再生体系,探讨了根尖内部维管组织在狗蔷薇愈伤-不定根根尖膨大发育为类原球茎过程中所起作用。剪切试验发现,脱离愈伤的狗蔷薇不定根根尖不能诱导类原球茎形成;桥接培养表明,通过维管组织向根尖运输外源激素TDZ诱导类原球茎发生的效率高于共质体运输方式;TIBA(2,3,5-triiodobenzoic acid)处理限制了根尖维管组织向分生区的延伸速度,并最终影响了类原球茎发生率;在类似狗蔷薇愈伤-不定根结构的蒺藜苜蓿(Medicago truncatula Gaertn.)根段-不定根上也重现了根尖被诱导发育为绿色球体过程。由此表明,愈伤-不定根中完整的维管组织是狗蔷薇类原球茎发生的结构基础之一,揭示获得与愈伤-不定根类似的内部结构和组合模式的外植体(如毛状根),并将其视为整体进行诱导培养,是建立月季类原球茎再生体系的前提之一。     

建兰类原球茎体生长、发育过程中扫描电镜观察

建兰(Cymbidium ensifolium)类原球茎体(PLB)培养在含3％蔗糖和不含蔗糖的1/2 MS_0培养基中生长,比较连续光照、8h光照和黑暗条件下原球茎生长发育的动态进程。扫描电镜观察表明:原球茎表面布满密集的发育程度不同的分生区,随继代培养进程,形成分株更多的丛生形原球茎,连续光照促进分生区的增殖,黑暗不利于分生区的发育,在无糖源培养基中生长的PLB,分生区的细胞伸长,发育呈管状结构,这种结构丧失分生能力。在原球茎顶端分化叶原基,并可分化类似气孔的保卫细胞。     

狗牙根花序发育过程的形态学观察

对狗牙根(Cynodon dactylon‘C299’)花序发育过程中的形态学变化进行了观察。结果表明,‘C299’花序的整个发育过程可分为8个阶段,即营养生长期、穗轴发生期、苞叶原基分化期、小穗原基分化期、小穗分化期、小花分化期、颖片和内外稃发育期及花药和柱头形成期。其中,穗轴发生期(直立茎上有6~9片叶)是抑制花序形成和决定种子产量的关键时期。     

盾叶薯蓣类原球茎发育的形态解剖学观察

为探讨盾叶薯蓣类原球茎形态建成的发育机理及植株移栽成活率高的原因,对盾叶薯蓣离体培养条件下形成类原球茎的形态发生过程进行形态学和石蜡切片组织学观察,并与不定芽的发生进行比较。结果表明：类原球茎是由愈伤组织中致密的卵圆形胚性细胞团分化出芽原基和鳞片叶,随后出现初生增厚分生组织和原形成层（维管束原）,其类原球茎形态建成。不定根的发生为内起源,其维管组织与类原球茎的维管组织相连接,故移栽成活率高。而不定芽为愈伤组织表面的胚性细胞分裂产生的分生细胞团分化而来,其不定根通常发生在茎基部形成的愈伤组织表面,故不易成活。     

孔雀鱼胚胎心血管发育的显微观察

心血管系统的组织分化研究是近年热点课题之一1.胚体透明且发育速度快的鱼类胚胎由于具备便于观察的特性2,正广泛用于脊椎动物造血系统的发生、血细胞生成、及血循环系统分化时序、调控因子等研究3-5.孔雀鱼(Poecilia reticulata Peters)是卵胎生(Ovoviviparity)鱼类的代表种,其卵子在雌鱼的泄殖腔内受精发育,长成鱼后再出生 ;同时孔雀鱼又是一种小型观赏鱼类,在实验室易于饲养,能不断提供实验用卵和胚胎。因此,在本实验室长期进行鱼类组织细胞培养的基础上6-11,制备孔雀鱼胚胎组织标本,并对早期胚胎及心血管系统进行了体外培养, 观察和比较了孔雀鱼胚胎心血管系统在体内、外的形成过程。       

狗枣猕猴桃果实发育的解剖学观察

对狗枣猕猴桃果实发育进行了显微和超微结构观察。其主要过程可分为：1、早期胚胎发育;多心皮合生子房,通常具16个心室,中轴胎座,中轴上着生大量倒生胚珠,单珠被,具珠被绒毡层,胚囊蓼型,授粉后约2-4h花粉萌发,授粉后约120h花粉管到达胚珠,受精后,初生胚乳核分裂先于合子。胚乳发育为细胞型。2、果壁：果壁可分为果皮,果肉和果心三部分,果皮较薄,由2-3层薄壁细胞组成。外表面光滑无毛,但覆有角质层,气孔下陷,分布于其中,果肉的大部分由薄壁细胞组成,分大,小两种细胞,小细胞含较多淀粉粒,淀粉粒的水解是果实软化的原因之一。果肉薄壁组织细胞还含有叶绿体及两种异细胞,一种异细胞内含物为结晶,普遍存在;另一种含被番红染成红色的絮团状物。果心由维管束和薄壁细胞组成,维管束不发达,3、种子：种皮外表面呈蜂窝状,种皮较硬,由两层细胞构成。线性直立胚,胚乳发达,主要贮藏物是蛋白质。     

狗枣猕猴桃果实发育的解剖学观察

对狗枣猕猴桃果实发育进行了显微和超微结构观察。其主要过程可分为：1. 早期胚胎发育：多心皮合生子房,通常具16个心室,中轴胎座。中轴上着生大量倒生胚珠,单珠被,具珠被绒毡层。胚囊蓼型。授粉后约2～4h花粉萌发。授粉后约120h花粉管到达胚珠。受精后,初生胚乳核分裂先于合子。胚乳发育为细胞型。2. 果壁：果壁可分为果皮、果肉和果心三部分。果皮较薄,由2～3层薄壁细胞组成。外表面光滑无毛,但覆有角质层,气孔下陷,分布于其中。果肉的大部分由薄壁细胞组成,分大、小两种细胞 ,小细胞含较多淀粉粒,淀粉粒的水解是果实软化的原因之一。果肉薄壁组织细胞还含有叶绿体及两种异细胞,一种异细胞内含物为结晶,普遍存在;另一种含被番红染成红色的絮团状物。果心由维管束和薄壁细胞组成,维管束不发达。3. 种子：种皮外表面呈蜂窝状,种皮较硬,由两层细胞构成。线性直立胚,胚乳发达,主要贮藏物是蛋白质。     

新疆灰绿藜花粉发育的显微观察

灰绿藜(Chenopodium glaucum L.)种子萌发后于温室(25℃)下培养30d左右,随机取300朵不同发育阶段的花蕾测量其大小(对生花被的最大距离)及花药大小(2个花粉囊的最大距离)。花粉取自不同发育阶段的花,经终浓度为2μg·mL~(-1)的与DNA强力结合的荧光染料4′,6-二脒基-2-苯基吲     

浒苔(Enteromorpha prolifera)藻体发育的显微观察

通过显微镜观察以及石蜡切片法观察了浒苔属浒苔藻体的发育过程,阐述了浒苔从孢子释放到形成成熟藻体这一发育过程的显微特征。结果表明:浒苔孢子由成熟体细胞分化发育而成,每个成熟体细胞可形成10～30个孢子;孢子首先分裂为2细胞结构,2细胞具有明显的极性,基细胞发育成为假根,顶端细胞不断进行横分裂形成丝状体;丝状体顶端以下细胞通过纵分裂形成管状叶状体,顶端细胞始终保持横分裂;纵分裂分为切向分裂与径向分裂,切向分裂增加管状叶状体管周细胞数从而使管体增大,径向分裂形成管外壁突起细胞,最终发育为分枝;管状叶状体管腔内部有绒毛状的突起及糖蛋白成分的网架结构;当管状叶状体管周细胞达到30～50h,管腔内部突起消失,网架结构收缩拉紧,管壁细胞贴近形成片状叶状体;整个浒苔藻体始终保持极性发育。     

Genetic differentiation of Rosa canina (L.) at regional and continental scales

We investigated the genetic differentiation of Rosa canina at regional and continental scales to delineate provenance regions for seed collection. Using RAPD technique, we examined eight populations in Brandenburg (Germany) and 13 samples from Bavaria and Hungary. AMOVA and $\upphiWe investigated the genetic differentiation of Rosa canina at regional and continental scales to delineate provenance regions for seed collection. Using RAPD technique, we examined eight populations in Brandenburg (Germany) and 13 samples from Bavaria and Hungary. AMOVA and -statistics revealed a significant differentiation ( = 0.23, P < 0.0001) between accessions from Brandenburg and the two other regions. The interpopulation differentiation in Brandenburg was low ( = 0.13). We found the greatest interpopulation distance between Hungary and Brandenburg (Hoher Fl?ming, = 0.47) and the lowest between Dahmeland and Hoher Fl?ming (both Brandenburg, = 0.01). UPGMA dendrogram and PCA showed a clear disjunction between Brandenburg and other regions. Due to the outcrossing mating and seed dispersal system, the genetic variation within R. canina populations is moderately high (87% for Brandenburg, 76% for Bavaria and Hungary). The significant genetic differentiation at the continental scale suggests lower gene flow with increasing geographical distance and underlines the usefulness of regional provenances for planting.     

Production of ROL gene transformed plants of Rosa hybrida L. and characterization of their rooting ability

Transgenic plants of the rootstock Rosa hybrida L. cv. Moneyway were produced via a two-step procedure. First, kanamycin-resistant roots were generated on stem slices from micropropagated shoots, which were cocultivated with Agrobacterium tumefaciens containing the neomycin phosphotransferase II (NPTII) gene for conferring kanamycin resistance, together with individual ROL genes from A. rhizogenes. Root formation was quite efficient and up to two kanamycin-resistant roots per stem slice were produced. In the second step, these roots were used to regenerate transgenic plants via somatic embryogenesis. Although regeneration lasted up to 12 months, production of several transformants was successfully accomplished. Untransformed escapes were not found, indicating that the initial selection on kanamycin resistance was reliable.The presence of a combination of ROLA, B and C genes enhanced adventitious root formation on micropropagated shoots and explants of stems and leaves. It appears that the auxin sensitivity was increased to such a degree that cells were able to respond even to endogenous auxins present in shoots and leaves. Rooting experiments in greenhouse demonstrated that adventitious root formation on cuttings was improved threefold upon introduction of these ROL genes. It is concluded that a method was developed for the production of ROL gene transformed roses with improved rooting characteristics.     

Paracrystalline inclusions of nutritive cells of galls induced by Diplolepis rosae L. on Rosa canina L

Numerous crystalline inclusions are found in the nutritive cells lining the larval cavities of the galls induced by Diplolepis rosae L. on Rosa canina L. Electron microscopic investigations show that these intracytoplasmic inclusions consist of staggered, closely parallel, and slightly wavy filaments. In each filament three fibrils can be distinguished inside a less electron-dense matrix. The different aspects that the filaments may present according to the section plans are studied with an electron microscope equipped with a goniometric stage. Enzymatic digestion of ultrathin sections show that the paracrystals are essentially composed of proteins. This conclusion is sustained by the results of an ultrastructural autoradiographic study using tritiated aminoacids. The physiological significance of these paracrystals is discussed: their presence is probably related to a larval action which stimulates proteosynthesis in the cells surrounding the consumed ones.     

Organogenesis and plant regeneration from immature embryos of Rosa hybrida L.

Intact, flowering, rose plants have been regenerated in vitro from excised embryos of crosses between Bridal Pink (the maternal parent) and several pollen parents. Explanted embryonic tissues developed into an organogenic callus which formed adventitious shoots after several months only on a modified half-strength Murashige & Skoog medium containing 1.0 M BA and 0.05 M NAA. These shoots could be separated, grown individually, rooted in a medium with no BA or NAA, with 1.0 M IBA, and transplanted to greenhouse media. Embryos ranging in age from 21 to 35 days post-pollination formed organogenic callus that eventually regenerated adventitious shoots. Histological examination of normally-developing embryos showed that well-defined embryonic axes were beginning to develop at approximately 20–25 days postpollination. Analysis of populations of regenerated plants from different crosses showed differences in flower color, growth habit, peduncle length, and petal number. This system may be useful for irradiation-mutation breeding and/or for the development of transgenic rose plants using Agrobacterium tumefaciens.Abbreviations BA 6-benzyladenine - IAA 3-indoleacetic acid - IBA 3-indolebutanoic acid - MS Murashige & Skoog - NAA -naphthaleneacetic acid - 2iP N⁶-(2-isopentenyl)adenosine     

Anticytokinin Effect on Apical Dominance Release in in vitro Cultured Rosa Hybrida L.

Effects of two cytokinin antagonists - 2-chloro-4-cyclobutyl-amino-6-ethylamino-1,3,5-triazine and N-(4-pyridyl)-O-(4-chlorophenyl)carbamate - on bud break and outgrowth in single nodes from two Rosa hybrida cultivars differing in their apical dominance were studied. The compounds were applied at three different concentrations separately or in combination with benzyladenine. Cytokinin antagonists reduced the number of the sprouted buds in both cultivars at different extent. Their effect was strongly dependent on both concentration applied and culture period duration. The replacement of anticytokinins with benzyladenine in the medium resulted in overcoming of the bud break suppression. Both compounds significantly inhibited bud outgrowth as well.     

蝴蝶兰原球茎增殖分化影响因子探讨

采用3个月胚龄的种胚播种形成的原球茎,初代培养时间在2.5~3个月之间换瓶转接,原球茎生长状况较好,分化形成的芽苗生长健壮;以1/2MS为基本培养基培养30d,原球茎增殖率达332%,MS培养基更有利于分化,培养2个月分化发芽率达90.6%;附加不同细胞分裂素原球茎的增殖率为6-BA >KT >Ad+KT >Ad;NAA浓度在0~1.0mg/L,对原球茎增殖分化影响不明显。     

生长素极性运输在水稻根发育中的作用

生长素极性运输(PAT)在植物生长发育尤其是极性发育和模式建成中起重要作用.采用2种PAT抑制剂TIBA(2,3,5-triiodobenzoic acid)和HFCA(9-hydroxyfluorene-9-carboxylic acid)处理水稻(Oryza sativa L. cv.Zhonghua)幼苗,结果表明:PAT影响水稻根发育包括主根的伸长、侧根的起始和伸长以及不定根的发育.PAT的抑制导致主根变短、侧根和不定根数目减少.外源附加生长素(NAA)可以部分恢复不定根的形成但不能恢复侧根的形成,表明在侧根和不定根的形成上可能具有不同的机制.切片结果表明,30μmol/TIBA处理后并不完全抑制侧根原基的形成,进一步研究表明生长素由胚芽鞘向基部的运输在水稻不定根的起始和伸长中起关键作用.     

Low genetic and morphological differentiation in the European species complex of Rosa sherardii,R. mollis and R. villosa (Rosa section Caninae subsection Vestitae)

The polyploid species complex of Rosa villosa sensu lato (Rosa section Caninae subsection Vestitae) consists of three morphologically similar polyploid species: R. sherardii, R. mollis and R. villosa. Whereas R. sherardii is distributed in central Europe, R. mollis and R. villosa represent a vicariant species pair occurring in northern Europe and in mountains of central and eastern Europe, respectively. In this study we analysed multiple data sets (morphology, cytology, microsatellites, AFLP and plastid DNA sequences) to re‐evaluate the systematics of these species and to examine whether cytological differences are reflected in the taxonomy and geographical distributions. Furthermore, these data sets were used to evaluate hypotheses explaining the vicariant distribution of R. mollis and R. villosa. None of these data sets revealed a clear‐cut differentiation between the species. Cytological and molecular data argued for a discrete taxonomic position of the predominantly pentaploid R. sherardii, but these data did not support a separation between the mostly tetraploid R. mollis and R. villosa. Population genetics revealed that samples of the latter species were assembled according to ploidy, but not to species affiliation or geographical distribution. Thus, we assume that the cytologically polymorphic original species had a continuous range prior to the last glaciation period and survived on nunataks or in non‐glaciated coastal regions in northern Europe, but that it failed to recover its former range after the retreat of the ice sheets. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 240–256.     

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     

GL生根剂对扶桑插条不定根皮层细胞超微结构的影响

研究了GL生根剂对扶桑插条不定根皮层细胞超微结构的影响。GL生根剂使皮层细胞中线粒体和内质网增加,液胞、线粒体和内质网膜有局部损害．经GL生根剂处理的皮层细胞含有的淀粉粒和脂质体数目较对照皮层细胞多．该实验结果为了解GL生根剂促进不定根形成的原因提供了细胞学基础．