浙江温州水稻根瘤状组织的结构分析

用光镜、扫描电镜和透射电镜观察的方法,对浙江温州水稻根上的瘤状组织进行了结构分析,并与豆科植物根瘤的结构进行了比较。壮苗期水稻的瘤状组织内皮层少数薄壁细胞内有细菌存在,但细胞有防御反应,细胞质凝聚和纤维化,分不清细胞质的精细结构,说明细胞已经死亡;孕穗抽穗期水稻根瘤状组织,表皮黑褐色,木栓化。外皮层内无维管组织,内皮层薄壁细胞膨大,但没有含菌细胞。有的瘤状组织内外皮层细胞基本上木质化。在内皮层薄壁细胞内有齿轮状的特殊结构。光镜和扫描电镜观察到的丝状物和珊瑚状花纹的球体,实为某种真菌的菌丝和孢子。因此,浙江温州的水稻根瘤状组织的结构与豆科根瘤完全不同,实为混有细菌和真菌的愈伤组织     

贵州苏铁根的解剖学研究

对贵州苏铁（Cycas guizhouensis K.M.Lan et R.F.Zou）的根进行了解剖学研究,结果表明：（1）据外部形态和内部结构不同,贵州苏铁的根可分为正常根、珊瑚状根和肉质根三种类型。（2）正常根与肉质根的木栓形成层起源于表皮内方第1～2层皮层薄壁细胞,珊瑚状根的木栓形成层则起源于外方皮层的第2～3层细胞,而非中柱鞘。（3）首次发现肉质根一种新的增粗方式,是由周皮内方的皮层薄壁细胞恢复分裂能力,持续或周期性产生新的皮层薄壁细胞,引起根的增粗。     

野芹菜体细胞胚胎发生早期变化的细胞学研究

通过光学与电子显微镜观察研究了野芹菜(Angelica polymorpha Maxim.)叶柄外植体胚性细胞的起源与原胚状体的发生。叶柄切段植入 MS 2mg/L2,4-D 0.25 mg/L KT固体培养基后,以DNA合成和细胞分裂为指标,判明了胚状体发生与紧贴维管束的鞘细胞层密切相关;鞘细胞通过有丝分裂形成多层结构的细胞群,它们仍含大液泡及薄层胞质,成片被覆在维管束表面;胚性细胞团即不同步地发生在该多层组织较内层的局部位点上,细胞具大核,胞质稠密,经持续有丝分裂发展成大小不同呈瘤状突起的原胚状体。伴随着鞘细胞的剧烈变化,韧皮部薄壁细胞亦分裂增殖,原有筛管变形衰退,部分新增殖的细胞分化为新筛分子;木质部中,原导管束附近朝向韧皮部一侧的部分薄壁细胞亦进一步分化为孔纹导管。外植体中维管系统的再次分化,显然是与输导功能强化以适应原胚状体发生时对营养物质的大量需求有关。     

黄芩根中木间木栓的形成与发育特性研究

应用光学显微镜和电子显微镜对3年生黄芩(Scutellaria baicalensis Georgi)根中木间木栓的形成及其发育过程进行了细致观察,以揭示黄芩木间木栓形成的特征以及发育过程中导管及周围薄壁细胞的变化,旨在为中药枯芩的形成提供理论依据和实验证据。结果表明：(1)黄芩根的次生结构由周皮、皮层和次生维管组织组成;木间木栓发生在木质部异常导管的周围,先是导管内出现侵填体或其他物质,接着这些导管邻近的部分薄壁细胞内也出现一些物质,随后导管外围的正常薄壁细胞恢复分生能力,产生木栓形成层,进而形成木间木栓。(2)木间木栓将健康组织与这些异常的导管和薄壁细胞隔离,隔离在内的组织会逐渐成为死亡组织。(3)横切面观,小木间木栓可同时或先后发生在木质部的不同位置,由内向外逐渐扩大,与周围的木间木栓相连,最终形成大的木间木栓。(4)纵切面观,木间木栓以管状形式由根头部向下延伸,部分根中距根头部以下3 cm内有木间木栓存在。     

贵州苏铁根的解剖学研究*

对贵州苏铁( Cycas guizhouensis K. M. Lan et R. F. Zou) 的根进行了解剖学研究, 结果表明: ( 1)
据外部形态和内部结构不同, 贵州苏铁的根可分为正常根、珊瑚状根和肉质根三种类型。( 2) 正常根与肉
质根的木栓形成层起源于表皮内方第1~ 2 层皮层薄壁细胞, 珊瑚状根的木栓形成层则起源于外方皮层的
第2~ 3 层细胞, 而非中柱鞘。( 3) 首次发现肉质根一种新的增粗方式, 是由周皮内方的皮层薄壁细胞恢
复分裂能力, 持续或周期性产生新的皮层薄壁细胞, 引起根的增粗。     

酚类化合物促进含双元载体农杆菌对胡萝卜悬浮细胞的转化和植株再生

含双元载体的非致瘤根癌农杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍ ｅｆａｃｉｅｎｓ） ＬＢＡ４４０４经乙酰丁香酮和复合酚类化合物活化预处理后,感染胡萝卜（Ｄａｕｃｕｓ ｃａｒｏｔａ）悬浮培养细胞,在含５０ ｍ ｇ／ＬＫｍ 的选择培养基上筛选Ｋｍ ｒ 克隆。实验表明：酚类化合物活化预处理组的转化率分别为０．２４％ 和０．１７％ ,而未经酚类化合物活化处理组的转化率仅为０．０２％ 。Ｋｍ ｒ 克隆在含５０ ｍ ｇ／Ｌ Ｋｍ 的无激素培养基上通过体细胞胚胎发生形成完整植株。组织化学分析表明：报告基因ＧＵＳ的活性可出现于Ｋｍ ｒ 克隆细胞、再生植株的根、茎、叶、叶柄维管束薄壁细胞、叶片的气孔保卫细胞、皮层细胞、叶肉细胞和毛状体、叶柄的表皮细胞和表皮下薄壁细胞     

杂交水稻体细胞胚胎发生及其再生植株的田间表现(简报)

杂交水稻小穗轴的单个薄壁细胞可以转变成非胚性愈伤组织或迅速分裂的细胞,后者可形成胚状体。与种子植株比较,胚状体植株没有明显的衰退现象。田间性状测定表明,胚状体植株较种子植株具有株形高、叶宽、穗长、穗多、空粒与实粒均多、谷粒长、谷长/谷宽比值大、单株产量高的特点。     

粗糙沼虾精子的超微结构研究

利用电镜及细胞化学方法,研究了粗糙沼虾（Ｍａｃｒｏｂｒａｃｈｉｕｍ ａｓｐｅｒｕｌｕｍ）精子的形态和超微结构。结果表明：精子无鞭毛、不运动,由后主体部、中间帽状体和前端棘突组成。主体部呈浅状,内有非浓缩的核,核内含有许多泡囊造近帽状体的核部,分布着许多膜本,膜层体与帽状体紧密相连。棘突具有间隔约３１ｎｍ的珏纹。环纹由直径为４～６ｎｍ的丝状体组成并与环纹相垂直。精子无明显的顶体区。     

香根草体细胞胚胎发生的细胞学特点与形成条件

香根草是一种优良的生态环境治理植物,但也存在着一些局限性。为了对香根草进行遗传改良,选育出性状更优、抗性更强的新品种,开展了香根草离体培养研究。离体培养采用了两种外植体,一是带腋芽的节,二是由器官发生方式所产生的无菌不定芽。基本培养基为MS,根据不同的目的附加不同种类或配比的生长素与细胞分裂素。观察到香根草的外植体的离体发育途径,有器官发生和体细胞胚胎发生两种,依培养基中所含细胞分裂素或生长素的种类和用量不同而异。结果表明,香根草的这两种离体发育途径的植株再生能力均可以长期保持。细胞学的研究显示,香根草离体发育的启动可在外植体的表皮细胞或薄壁细胞中进行,这些细胞逐渐发育成为胚性细胞。胚性细胞分裂活跃,经二细胞、四细胞而发育成为多细胞的胚性细胞团。由显微观察可知,香根草的体细胞胚胎发生是单细胞起源的,成熟的体细胞胚具有单子叶植物典型的胚胎结构。在分化培养基的作用下,体细胞胚组织上所有的胚状体可以出芽而形成再生植株。所建立的香根草体细胞胚胎发生的植株再生体系,完全适用于遗传转化等生物工程方法对离体培养要求。此外,还观察到一些一般只有在双子叶植物才出现的鱼雷形体细胞胚,这是体细胞胚胎发生中的异常现象。认为这种异常胚是离体培养所引起的。     

狗蔷薇类原球茎发育过程的显微观察

对狗蔷薇类原球茎发育进行显微观察的结果表明：类原球茎发育过程中外部形态发生了明显的变化;毛状不定根及其产生的类原球茎均具备根的结构特点;类原球茎由毛状不定根中维管柱顶端外围的中柱鞘薄壁细胞发育而来,是包括胚性细胞和薄壁细胞在内的囊腔状结构的复合组织,胚性细胞在类原球茎中的发育经历了原胚、球形胚、心形胚和鱼雷胚阶段,并且与周围的细胞存在明显的生理隔离;类原球茎具有明显的极性,并且可以重复发生形成次类原球茎。     

DEVELOPMENT AND STRUCTURE OF THE VASCULAR CONNECTION BETWEEN THE PRIMARY AND LATERAL ROOT OF LYCOPERSICON ESCULENTUM

The primary xylem connection between the diarch parent root and the diarch lateral root was derived from the pericycle and stelar parenchyma. Early in lateral root development stelar parenchyma that was positioned between the parent xylem and the primordium divided transversely. These transverse divisions produced a plate of cells, most of which subsequently differentiated into vessel element connectors. After emergence of the lateral root, xylem maturation began in the stelar vessel element connectors and maturation proceeded acropetally into the lateral root. Protoxylem of the lateral root was connected to the metaxylem of the parent root via stelar vessel element connectors. The circular phloem connection was pericyclic in origin. Axial phloem connections which vascularized the lateral root were established with sieve tube elements of both parent phloem poles. Maturation of the phloem connection occurred prior to lateral root emergence. Transaxial phloem, positioned in arches above and below the lateral root vascular cylinder, was derived from the pericycle; and each arch consisted of three to four sieve tube elements. No transfer cells were found in the transaxial phloem.     

Properties of peach flower buds which facilitate supercooling

Water in dormant peach (Prunus persica [L.] Batsch. var. `Harbrite') flower buds deep supercooled. Both supercooling and the freezing of water within the bud axis and primordium as distinct components depended on the viability of the bud axis tissue. The viability of the primordium was not critical. Supercooling was prevented by wounding buds with a dissecting needle, indicating that bud structural features were important. Bud morphological features appeared to prevent the propagation of ice through the vascular tissue and into the primordium. In dormant buds, procambial cells had not yet differentiated into xylem vessel elements. Xylem continuity between the bud primordium and adjacent tissues did not appear to be established until buds had deacclimated. It was concluded that structural, morphological, and physiological features of the bud facilitated supercooling.     

绞股蓝营养器官的结构及其人参皂甙的组织化学定位研究

绞股蓝是多年生草质藤本植物。根系由不定根组成,根的初生结构木质部为2－4原型,次生结构中栓内层较厚,攀缘茎,具5棱,周围纤维连成一环,幼茎的维管束排成两圈,外圈5个,内圈4或5个,老茎圆柱形,周围纤维呈不连续环状,维管束具次生木质部和次生韧皮部,排成一圈,掌状复叶互生,小叶5－7片,背腹型,叶柄具5束维管束,进入小叶时分为7－9束,茎和叶的初生维管束为双韧维管束,组织化学实验表明,绞股蓝人参皂甙主要分布在营养器官的同化组织及韧皮部薄壁细胞中,厚角组织,表皮及周皮的栓内层也有少量分布。     

白鲜营养器官解剖结构及其与白鲜碱的积累关系

应用植物解剖学、组织化学及植物化学方法对白鲜营养器官根、茎、叶的结构及其生物碱的积累进行了研究。结果显示:(1)白鲜根的次生结构以及茎和叶的结构类似一般双子叶植物;白鲜多年生根主要由周皮、次生韧皮部、维管形成层以及次生木质部组成,根次生韧皮部中可见大量的淀粉、草酸钙簇晶、韧皮纤维以及油细胞;茎由表皮、皮层、维管组织和髓组成;叶由表皮、栅栏组织、海绵组织和叶脉组成;在茎和叶初生韧皮部的位置均分布有韧皮纤维,在叶表皮上分布有头状腺毛和非腺毛;在茎和叶紧贴表皮处分布有分泌囊。(2)组织化学分析结果显示:在白鲜多年生根中,生物碱类物质主要分布在周皮、次生韧皮部、维管形成层和木薄壁细胞中;在茎中,生物碱主要分布在表皮、皮层、韧皮部、木薄壁细胞及髓周围薄壁细胞中;在叶中,生物碱主要分布在表皮细胞、叶肉组织和维管组织的薄壁细胞;此外在分泌囊和头状腺毛中亦含有生物碱类物质。(3)植物化学结果显示,秦岭产白鲜根皮/白鲜皮、根木质部、茎和叶中白鲜碱含量分别为0.041%、0.012%、0.004%和0.002%,其中木质部中白鲜碱含量和其他部分地区白鲜皮中白鲜碱含量类似。研究表明,在秦岭产白鲜营养器官中,除根皮/白鲜皮外,在根木质部亦含有大量的白鲜碱,且在茎和叶中亦含有一定的白鲜碱,具有潜在的开发利用价值。     

The endophytic system of mediterranean Cytinus (cytinaceae) developing on five host Cistaceae species

BACKGROUND AND AIMS: One of the most extreme manifestations of parasitism is found in the genus Cytinus, a holoparasite whose vegetative body is reduced to an endophytic system living within its host root. There are two species of Cytinus in the Mediterranean, C. hypocistis and C. ruber, which parasitize various genera of Cistaceae, one of the most characteristic families of the Mediterranean scrublands. The aim of this work is to describe the endophytic systems of C. hypocistis and C. ruber, and their tissue relationships with their host. METHODS: Roots from five different hosts infected with C. hypocistis and C. ruber were harvested, and examined by anatomical techniques under light microscopy to elucidate the characteristics of the endophytic system of Cytinus, and to determine if differences in endophytic systems occur between the two species and in response to different hosts. KEY RESULTS: The endophyte structure is similar in both Cytinus species irrespective of the host species. In the initial stages of the endophyte, rows of parenchymal cells spread through the host pericyclic derivatives and phloem, and begin to generate small nodules in the outermost region of the host xylem. Later the nodules anastomose, and bands of parasitic tissue are formed. The host cambium continues to develop xylem tissue, and consequently the endophyte becomes enclosed within the xylem. The bands of parasitic tissue fuse to form a continuous sheath. This mature endophyte has well-developed vascular system with xylem and phloem, and forms sinkers with transfer cells that grow through the host xylem. CONCLUSIONS: The endophytic system of Cytinus develops in all host root tissues and reaches its most mature stages in the host xylem. It is more complex than previously reported, showing parenchyma, xylem and phloem tissues. This is the first report of well-developed phloem in a holoparasitic endophytic species.     

木立芦荟叶的发育解剖学研究

应用植物解剖学方法研究了木立芦荟（Aloe arborescens Mill.)叶的发育过程。研究结果表明,叶原基在发育早期其形态是不对称的,内部为同形细胞组成,但很快分化成原表皮,原形成层束和基本分生组织。以后,原表皮发育成表皮,位于原表皮下的2－5层基本分生组织细胞发民同化薄壁组织,而位于中央的基本分生组织细胞则发育成储水薄壁组织,原形成层束发育成维管束。维管束由维管束鞘、木质部、韧皮部和大型薄壁细胞组成。大型薄壁细胞起源于原形成层束,位于韧皮部内,其发育迟于筛管、伴胞,为芦荟属植物叶的结构特征。     

Morpho-Histological Investigation of Plantlet Formation In Vitro in Taiwania flousiana Gaussen

Histological events during adventitious shoot formation in cultured shoot apex of 10–12-day-old seedlings and adventitious root formation in the elongated shoot of Taiwania floudana Gaussen were examined. Ceils of the peripheral subsurface layers of the shoot apex responded to cytokinin and divided into meristematic cells from which the shoot primordia were proliferated. A few bud primordia also originated from the epidermis and hypodermis of the adaxial surface of the cotyledon. The parenchyma of leaf gap of the shoots cultured in rooting medium dedifferentiated to regain the capacity of division and form adventitious root. Besides, cells that had relatively low potential of differentiation, such as the cortex parenchyma, pith ray, phloem parenchyma and cambium zone, albeit initiated to divide, but seldom formed root primordium. The origin of the adventitious roots in the leaf gap facilitated the establishment of the vascular connection between the shoot and root.     

Structure and Development of the Axillary Complex and Extrafloral Nectaries in Capparis retusa Griseb.

Abstract: The structure, organization and development of the axillary complex and extrafloral nectary in Capparis retusa Griseb. was analysed for the first time. The axillary complex presents three uniserial descending buds. Subordinated shoots originate from the distal and middle bud, while the proximal bud is usually quiescent. Close to the top of the axillary complex there is a subglobulous and umbilicated extrafloral nectary, normally visited by nectivore ants; a chronological coincidence between secretion, production and ant patrolling activities has been observed. The nectary structure differentiates at the second caulinar node, from an axillar meristem separated from the surrounding cells by a shell zone. On the fourth node a remarkably developed nectary primordium can be observed, inside which procambial strands develop acropetally. In the central region of the nectary primordium homogenous parenchyma differentiates progressively, later acquiring characteristics of nectariferous tissue. The mature nectary is vascularized by xylem and phloem, and the procambial differentiation is completed in a basipetal way. The first serial bud differentiates at the third node, from meristem cells near the base of its supporting leaf. The complex nodal structure with three buds completes its development at the eighth caulinar node. Ramular traces are observed as vascular semicylinders penetrating into the base of the buds to constitute a vascular system similar to that of the shoot. The scheme is repeated in the extrafloral nectary, giving rise to prolific branching in the periphery of the nectariferous tissue.     

The Formation of Adventitious Roots and Buds in the Petiole of Detached Leaf of Pelargonium Graveolens

Median sized leaves of Pelargonium graveolens L'Her. after being excised from the middle of the petioles were planted in quartz sand or common sand in greenhouse. After one week in culture, calluses were formed aberrantly at the wound surface of the petioles of most of the detached leaves. By the second week, adventitious roots initiated somewhere in the callus close to the vascular tissue of the splitted base of the petiole. Adventitious buds also initiated from the callus, but they were not related to the vascular tissue in the origin. There were two different modes of initiation: one from the depth of the callus (endogenous) and the other near its surface (exogenous). Soon after, the distal end of the bud primordium became flattened (most of them became inverted triangular in outline) as was seen in the longitudinal section. Later, the middle part of the distal end became depressed and differentiated into the first leaf primordium and the apical meristem. As the young bud became further elongated, the leaf primordia were consecutively formed. Consequently the structure of the adventitious buds approached normal. The apical portion emerged from the sand was similar to the mature one in structure.     

田旋花营养器官及不定芽发生的解剖学研究

对田旋花营养器官的解剖学研究结果表明,叶为两面叶,栅栏组织和海绵组织发达。主脉为周韧型维管束,在其主脉的远轴面,紧领下表皮的为1－2层同化组织细胞。地上茎表皮内具由2层细胞组成的同化组织,维管组织呈连续的环状排列,木质部内外侧都为韧皮部。地下根状茎的结构类似地上茎的结构,维的维管组织发达,在次生生长中,中央初生木质部导管周围薄壁细胞分化产生大量薄壁细胞和韧皮部分子。根状芭茎上的不定芽及不定根由维管形成层活动产生,根上的不定芽也是由根的维管形成层产生。