毛钩藤的小孢子发生和雄配子体发育

在光学显微镜和透射电镜下观察了毛钩藤(Uncaria hirsuta Havil.)的小孢子发生和雄配子体发育过程.结果表明,毛钩藤花两性,具5枚雄蕊,花药4室,花药壁由表皮、药室内壁、中层和绒毡层组成,花药开裂时,药室内壁高度纤维化带状加厚.花药壁的发育方式属于双子叶型,小孢子母细胞减数分裂的胞质分裂为同时型.小孢子在四分体时期开始沉积花粉外壁,小孢子大液泡化时期开始沉积花粉内壁.成熟花粉为2-细胞型.毛钩藤的花粉发育特征和茜草科植物基本一致.毛钩藤绒毡层属于分泌型,双重起源,分别起源于次生周缘层和药隔细胞.小孢子发育早期绒毡层开始降解并分泌形成大量乌氏体,花药开裂时绒毡层完全消失,剩下少量乌氏体.小孢子早期内壁加厚突出形成,小孢子细胞核分裂以后内壁加厚开始脱落,花药开裂时,只剩下少量的内壁加厚突出.初步推测,内壁加厚突出与乌氏体共同作用为雄配子体的发育提供营养物质.     

一品红雄配子体发育研究

一品红花药来源于雄蕊原基,花药由表皮(1层)、药室内壁(1层)、中层(1层)、绒毡层(1层)及造胞细胞组成,花药四室,药壁发育为双子叶型。小孢子发生和雄配子体发育是经由小孢子母细胞减数分裂形成四分体,该四分体胞质分裂为同时型,四分体排列为四面体型,小孢子再经有丝分裂形成2-核花粉。花药壁层的变化是表皮在花药成熟期消失,中层在四分体时消失,药室内壁在花药成熟期形成柱状纤维层。绒毡层在单核小孢子期径向伸长,有双核或多核,另外有的绒毡层细胞形成横隔或类胎座;进入2-核花粉期,绒毡层细胞分泌颗粒物进入药室,为非典型腺质绒毡层;进入成熟期绒毡层消失。同时观察到花药发育异常现象。     

七叶树小孢子发生及雄配子体发育研究

用石蜡切片法观察了七叶树花药的发育过程.结果表明:(1)雄蕊花药四室,花药壁完全分化时,从外到内依次是表皮、药室内壁、中层和绒毡层,花药壁发育为基本型.表皮细胞1层,发育过程中始终存在;药室内壁在花药成熟时形成带状纤维层加厚;幼小花药壁的中层3~4层细胞,在花药发育成熟时退化消失;绒毡层1层细胞,发育类型为分泌型,小孢子母细胞减数分裂时绒毡层开始退化解体,花药成熟完全消失,仅剩1层绒毡层膜.每一花药中有多列雄性孢原细胞,发生于幼小花药表皮下方;(2)小孢子母细胞减数分裂为同时型,四分体多呈正四面体排列;减数分裂过程中,小孢子母细胞外方被胼胝质壁所包被,小孢子形成后胼胝质壁逐渐消失.成熟花粉二细胞型,外形呈圆三角状,具三孔沟.     

凤仙花花药发育特征

凤仙花花药发育比较特殊: 在造孢细胞时期,花药横切面中央是体积较大、细胞内含物较多的细胞团、包括造孢细胞和绒毡层细胞。花药药壁细胞的细胞质较稀少,与中部细胞界限明晰。花粉母细胞时期的花药药壁由约6层细胞组成,但细胞的界限不明显;绒毡层细胞显示变形流入药室中。到四分体时期,绒毡层细胞进一步退化。开花时,成熟花药的药壁细胞由一层表皮细胞、两层药室内壁细胞和一层中层细胞组成。对凤仙花花药绒毡层的特殊性质进行了讨论。     

胡萝卜花药发育的组织化学研究

胡萝卜四分体时期的花药在药室内壁和绒毡层细胞中积累淀粉粒,随着花药的发育,花粉先出现大液泡,同时药室内壁和绒毡层细胞中淀粉粒消失;以后花粉中的大液泡消失,在花粉细胞质中出现淀粉粒。伴随着花粉的发育,绒毡层细胞退化,在细胞中积累较多的脂类物质,同时花粉中脂类物质含量也明显增加。胡萝卜成熟花粉粒的储存物主要为脂滴,也有少部分淀粉颗粒。胡萝卜花药在特定时间和特定部位积累营养储存物的过程也是其发育的一个特征。     

巴戟天花药发育过程中多糖和脂滴分布特征

巴戟天花药发育中多糖和脂滴类物质的分布呈现一定的规律：减数分裂之前,花药壁的绒毡层细胞中有少量脂滴,其他细胞中脂滴和淀粉粒都很少。四分体时期,四分体小孢子中开始出现脂滴,绒毡层细胞中的脂滴较以前增加,其他细胞中的脂滴和淀粉粒仍然很少。小孢子早期,游离小孢子在其表面形成了花粉外壁,靠外壁下方有一层周缘分布的多糖物质。绒毡层细胞中的脂滴明显减少。发育晚期的小孢子中形成一个大液泡,细胞质中出现淀粉粒;同时在药壁和药隔组织中也出现了淀粉粒。此时绒毡层退化。在二胞花粉早期,花粉中积累了大量淀粉粒和一些脂滴。但在成熟的花粉中（二胞花粉晚期）,淀粉粒消失,只有一定数量的脂滴保留。巴戟天成熟花粉中积累的营养物质主要为脂滴。     

凤仙花花药发育中多糖和脂滴组织化学研究

以不同发育时期的凤仙花花药为实验材料,采用组织化学方法,对花药发育中的结构变化及多糖和脂滴物质分布进行观察。结果表明:(1)凤仙花的花药壁由6层细胞组成,包括1层表皮细胞,2层药室内壁细胞,2层中层细胞和1层绒毡层细胞。其中绒毡层细胞的形态不明显,很难与造孢细胞区分,且在小孢子母细胞时期退化。(2)在小孢子母细胞中出现了一些淀粉粒,但减数分裂后,早期小孢子中的淀粉粒消失,又出现了一些小的脂滴;随着花粉的发育,小孢子形成大液泡,晚期小孢子中的脂滴也消失;小孢子分裂形成二胞花粉后,营养细胞中的大液泡降解、消失,二胞花粉中又开始积累淀粉;接近开花时,成熟花粉中充满细胞质,其中包含了较多的淀粉粒和脂滴。(3)在凤仙花的花药发育中,绒毡层细胞很早退化,为小孢子母细胞和四分体小孢子提供了营养物质;其后的中层细胞退化则为后期花粉发育提供了营养物质。     

橡胶树花药和小孢子发生与发育过程的观察

应用石蜡切片法,观察橡胶树的实生树和RRIM600、CT-1品系的花药壁以及小孢子的发生和发育过程,得到如下结果:1.实生树的花药壁通常由四层细胞组成,发育形式为双子叶型。药室内壁细胞在发育后期进行径向条纹加厚,至花药开裂时仍保留着原生质体。中层由一层或不规则的两层细胞组成,在小孢子单核期消失。绒毡层细胞具单核或双核,属分泌型,至花粉发育到三细胞时消失。小孢子母细胞减数分裂为同时型。成熟花粉粒具三个细胞。精细胞椭圆形,在光镜下不能区分出细胞质鞘和核仁。所观察的实生树雄花,多数发育正常,很少有空秕的花粉。2·RRIM600品系的花药和小孢子发生与发育和实生树相似,但至后期只有少数花粉发育正常,多数成为大小不等的败育花粉;此外也有一些败有的雄花。3.GT-1的花药在小孢子母细胞减数分裂时,绒毡层细胞的体积开始异常增大并液泡化,小孢子在四分体内解体或分离后成为空秕花粉。     

水稻成熟花药和花粉的结构和组织化学研究

用乙二醇甲基丙烯酸脂(简称GMA)和环氧树脂Epon812包埋的薄切片方法对水稻成熟花药和花粉的结构进行了观察,并对各种结构的性质和细胞中的后含物做了细胞化学的分析.对成熟花药的绒毡层膜及乌氏体的研究采用了分离技术,做了显微和超微观察.证明水稻成熟花药壁和花粉除具一般禾本科植物特征外,还揭示了花药壁表皮上可能有硅质,药壁表皮细胞内含有脂类颗粒,药室内壁具纤维素质的纤维状加厚;发现花粉粒中除了贮存有大量淀粉颗粒外,还含有脂类,成熟花粉中营养核与两个精细胞及两个精细胞间联系紧密;并讨论了薄切片的优越性,绒毡层膜的意义及其上细胞印迹的来源.     

铁皮石斛花粉块结构及发育过程的解剖学特征研究北大核心CSCD

兰科植物的有性生殖特殊,每朵花只有1个花药,且花粉有聚集成块发育的特征。为了揭示铁皮石斛花粉块的发育特征,该研究以野生铁皮石斛不同时期的花药为材料,采用半薄切片和植物组织化学方法对其发育过程进行解剖学观察分析,并对成熟花粉块进行离体培养,观察花粉管的萌发状况。结果表明:(1)铁皮石斛花药壁由1层表皮细胞,2层药室内壁细胞,1层中层细胞和1层绒毡层细胞组成。开花时,绒毡层细胞退化,中层细胞没有退化,药室内壁细胞则形成纤维状细胞壁;药室中的小孢子母细胞没有明显的胼胝质壁结构。(2)小孢子发生属同时型,减数分裂后四分体小孢子不分散,以四合花粉状态发育,并进一步连接形成花粉块。(3)在小孢子发育中,孢粉素覆盖在整个花粉块表面形成花粉外壁,但花粉块内部的花粉没有花粉外壁结构;在花粉块表面的花粉外壁上未见花粉萌发孔。(4)在花粉离体萌发实验中,具有花粉外壁的花粉块表面花粉未见萌发,仅由花粉块内部的花粉萌发出花粉管。     

Microsporogenesis and exine structure in Trochodendron aralioides Siebold and Zuccarini (Trochodendraceae)

This study aimed to elucidate the anther wall development, pollen wall development, and exine structure of Trochodendron aralioides Siebold and Zuccarini, a tree with primitive vessels but long considered to lack vessel elements in its wood. The anther wall is the basic type: epidermis, endothecium layer, three middle layers, and tapetum. The anther tapetum is glandular and cells are uniseriate. Microspore mother cells undergo meiosis with simultaneous cytokinesis to produce tetrahedral tetrads enclosed within a callose wall. Before development of the protectum, primexine is inserted against the callose, and the plasma membrane is invaginated. Then, the probacula are elongated under the protectum and arise basally from the plasma membrane. The foot layer formation is concomitant with callose wall dissolution. The foot layer is thick, and the endexine is thin. The foot layer and the endexine are both continuous. The intine is initially formed in the vacuolated microspore stage. Hollow Ubisch bodies are observed on the inner surface of the tapetum in free microspore stage. Pollen grains are tricolporate and 2-celled at the time of shedding. The numerous anthers of a single flower are at different development stages in both protandrous and protogynous individuals.     

水稻花药绒毡层及乌氏体的超微结构观察

在花粉母细胞期,水稻花药绒毡层细胞原生质浓,细胞器丰富,各轴向壁厚度较一致．随着药室腔扩大,绒毡层细胞体积迅速增大,且外切向壁增厚,径切向壁部分区域消失,细胞间形成原生质桥．在单胞花粉早期,乌氏前体排列于绒毡层内切向细胞膜内,随后移向膜外,且外侧增厚形成乌氏体．在花粉单核靠边期,绒毡层细胞的细胞器开始解体,到花粉充实期完全解体,但乌氏体结构直到花粉成熟保持不变．     

Pollen development of Cardiocrinum giganteum (Wall.) Makina in China

In this article, we studied the pollen morphology and wall development, microsporogenesis, male gametophyte development, and anther wall structure changes during pollen development of Cardiocrinum giganteum (Wall.) Makina from the genus Cardiocrinum (Endl.) Lindl. (Liliaceae) using paraffin sections, scanning and transmission electron microscopy, and fluorescence microscopy. The results showed that C. giganteum has oval-shaped pollen with a single sulcus and reticulate ornamentation. The exine is of the semi-tectum type and can be divided into the tectum layer, columellate layer and basal layer. Meiosis in the microsporocyte is accompanied by successive cytokinesis. The mature pollen is three-celled. The anther wall prior to maturity is built by one layer of epidermis, 1–2 layers of endothecium cells, 4–5 middle layers and 2 layers of tapetum, while upon maturity it is only built by one layer of epidermis, one layer of endothecium cells and one middle layer. The tapetal cells are secretory, with two or more nuclei. Ubisch bodies originate from rough endoplasmic reticulum except a few from mitochondria.     

STUDIES IN THE BIGNONIACEAE. I. ONTOGENY OF DIMORPHIC ANTHER TAPETUM IN PYROSTEGIA

Development of the anther wall was studied with special reference to the tapetum in Pyrostegia ignea. The archesporium in each microsporangium is horseshoe-shaped. The inner tapetum develops earlier from the vegetative cells of the connective region while the outer differentiates a little later from the parietal layers. Thus, the tapetum has a distinct dual origin. The two tapetal layers exhibit a pronounced structural dimorphism. Sometimes, sterile septae, partitioning the sporogenous tissue, develop in microsporangia. A prominent membrane with Ubisch granules (orbicules) is organised on the inner tangential surface of the tapetal protoplasts facing the uninucleate microspores.     

Anther ontogeny in Campsis radicans (L.) Seem. (Bignoniaceae)

In this study anther ontogeny of Campsis radicans (L.) Seem. was investigated by transmission electron microscopy and light microscopy with special reference to the development of the anther wall. The anther wall formation follows the dicotyledonous type. The differentiation in anther starts with the appearance of archesporial cells which undergo periclinal divisions to give primary parietal layer to the epidermal site and the primary sporogenous cells to the inside. The primary parietal layer also divides to form two secondary parietal layers. Later, the outer secondary parietal layer (spl1) forms the endothecium and the middle layer by periclinal division whereas the inner one (spl2) directly develops into the outer tapetum forming the inner most layer of the anther wall. The sporogenous tissue is generally organized in two rows of cells with a horseshoe-shaped outline. The remainder of the tapetum lining the sporogenous mass is derived from the connective tissue. The tapetum thus has dual origin and dimorphic. Anthers are tetrasporangiate. The wall of the anther consists of an epidermis, endothecium, middle layer, and the secretory type tapetum. Tapetal cells are usually binucleated. Epidermis and Endothecium layers of anther wall remain intact until the end of anther and pollen development; however, middle layer and tapetum disappear during development.     

麦冬花药绒毡层和乌氏体的细微结构

麦冬(Ophiopogon japonicus)的绒毡层发育为分泌型。在小孢子母细胞时期,绒毡层细胞达到了发育的高峰。此时,绒毡层细胞中细胞器非常丰富,具大量线粒体、高尔基体和质体,尤以肉质网含量最多;原乌氏体出现较早,在小孢子母细胞时期绒毡层细胞中就已出现;四分体时期,大量原乌氏体被排入内切向面的质膜和纤维素壁之间;到了小孢子早期,绒毡层细胞失去细胞壁,原乌氏体分布在质膜的凹陷处,孢粉素物质在其上沉积,发育为乌氏体,乌氏体有单个和复合两种类型;当花粉成熟时,绒毡层细胞完全解体。     

Development and Histochemical Observations of Tapetum and Peritapetal Membrane in Anther of Pulsatilla chinensis

Tapetum of Pulsatilla chinensis is of secretory type. Its development proceeds rapidly in following sequence: (1) The stage of initiation-differentiation. At this stage cytological and histochemical features have been described in detail in this paper. (2) The stage of growth- synthesis: This stage appears to be the most important anabolic phase during the development of the tapetum. The salient features are that the tapetal cells become relatively enlarged and form two polyploid nuclei or aberrent polyploid nuclei resulting in synthetizing maximum proteins, fluorescing substances and maximum fluorescent Pro-Ubisch bodies in the tapetal cytoplasm. (3) The stage of secretion-disorganization: After the disintegration of the tapetal wall the enlarged naked cells appear at once. This is an important secretion period in which Pro-Ubisch bodies as well as all other fluorescing substances, carbohydrate or some enzymes are released into anther loculus. The naked cell layer becomes disorgnized until the beginning divition of the pollen grains into two ceils. As to peritapetal membrane of P. chinensis, mainly based on the membrane being on the outer side of the tapetum enclosing both the pollen, tapetal cytoplasm and Ubisch bodies, and the cellular configurations facing the pollen, Authors postulate that peritapetal membrane might be survival of the cytoplasmic membrane of tapetal cells. However, the peritapetal membrane of P. chinensis is similar to that of plasmodial, tapetum reported in certain Compositae and that of secretory tapetum reported in Pinus banksiana. Heslop-Harrison and Gupta et al. had conceded that the tapetal and peritapetal membrane belong to the general class of sporopollenin. On the contrary in P. chinensis the sporopollenin property of peritapetal membrane is only confined to its inner surface. But the thin mem- brane itself with the reticulate sporopollenin attched on its inner side appears negative staining reactions for sporopollenin though it has an ability to resist the acetolysis as well. In P. chinensis the Ubisch body is short necked flask shaped and their size is very similar. Ubisch body is either single or 2–5 in a group, resulting in compound bodies. When the Pro-Ubisch body is still within the tapetal cell it shows positive fluorescent reaction, while it eomletely unstains with Teluidine blue O. So Authors infer that the sporopollenin precur- sors may have permeated through Pro-Ubisch bodies. Finally, How sporopollenin precursor is synthesized in the tapetal cells, transported to pollen locula and polymerized into the sporopollenin on pollen, Ubisch body and peritapetal membrane? Future works along these problems may yield fruitful results.     

文冠果可孕花与不孕花发育过程的比较研究简

利用半薄切片和透射电镜技术对文冠果可孕花和不孕花的发育过程进行观察和比较。结果显示：(1)小孢子发育初期,两种类型花花药形态无明显差别;小孢子发育双核期,可孕花花药内壁纤维层细胞壁带状加厚,无唇细胞形成。而不孕花花药同侧两个花粉囊之间唇细胞正在分化;小孢子发育成熟期,不孕花花药唇细胞完全形成;散粉期,不孕花花药开裂呈双心形,而可孕花花药则不能开裂散粉。(2)可孕花雌蕊子房内有两室,柱头细胞排列紧密,柱头逐渐发育成圆球形,周围密布乳突细胞,具中空花柱道;不孕花雌蕊柱头停止发育,无中空花柱道,子房室变小,胚囊发育退化。(3)不孕花花药绒毡层中含大量蛋白体,小泡以及乌氏体等细胞器,发育后期绒毡层解体。而可孕花花药绒毡层中细胞器和营养物质积累均较少,发育后期绒毡层解体不完全。(4)可孕花花药内花粉粒细胞壁连续无萌发孔,细胞内含物较少。不孕花花药内花粉出现3个向内凹陷的萌发孔,且花粉内含有大量造粉质体和脂类物质。     

雄性不育与可育楸树花发育的细胞学比较研究

楸树（Catalpa bungei C.A.Meyer.）属紫葳科(Bignoniaceae)梓树属(Catalpa),落叶乔木,是我国特有的珍贵优质用材树种。本文用石蜡切片法对可育株和雄性不育株楸树的大、小孢子发生及雌、雄配子体发育过程进行了详细地比较观察。结果表明：可育株和不育株楸树雌蕊的发育基本相同,胚珠倒生,薄珠心,单珠被,胚囊发育为蓼型。可育株雄蕊花药四室,药隔薄壁组织发达;异型绒粘层,由药壁绒粘层和药隔绒粘层组成;花药壁表皮细胞在小孢子母细胞减数分裂前后开始径向伸长加厚,直到花药开裂并不降解,这可能与花药开裂有关;成熟花粉为四合花粉。雄性不育株花药的早期发育到次生造胞细胞时期与可育雄蕊的相同,小孢子母细胞减数分裂前绒毡层发育不充分;四分体时期,绒毡层细胞高度液泡化,细胞质稀薄,已提前降解,小孢子四分体因绒毡层结构和功能异常而不能正常发育,因此楸树雄性不育为结构型雄性不育。