雄性不育和雄性能育小麦(Triticum aestivum L.)花药和花粉发育的细胞形态学观察

本工作是小麦雄性不育杂种优势利用研究项目的一部分。从细胞形态学的角度,研究小麦细胞质雄性不育系及其保持系花药和花粉的发育,为探索雄性不育性的机理提供资料。应用石蜡切片法,对小麦“早熟1号”和“北京8号”细胞质雄性不育系及其保持系花药的发育过程进行了观察,得到如下的结果:(1)不育系花粉的败育,在发育的各个时期都发生,但败育的关键时期是在小孢子发育后期,具大液泡的小孢子不能进入配子体发育阶段。(2)不育系花药和花粉的发育,在小孢子发育早期以前,90%以上与保持系相似,是正常的;少数表现异常而导致败育。异常现象有:药室合并;小孢子母细胞解体,绒毡层发育正常;小孢子母细胞互相粘连,形成多核的原生质团;解体的小孢子母细胞与绒毡层融合形成多核的原生质团;药室中除正常发育的小孢子母细胞或小孢子外,还出现异常的巨型细胞;绒毡层提早在小孢子发育早期解体,形成多核的原生质困;绒毡层肥大生长。     

大白菜新型细胞质雄性不育系6w-9605A的育性鉴定和花药败育的细胞学观察

采用石蜡切片技术,研究了大白菜(Brassica campestris L.ssp.pekinensis)细胞质雄性不育系6w-9605A及其保持系6w-9605B的花药发育过程的细胞形态学特征,确定不育系花药败育时期及方式,并对不育系6w-9605A进行花器官观察和育性鉴定.结果表明:保持系6w-9605B花药发育正常;不育系6w-9605A花药发育受阻于孢原分化时期,占总败育花药的66.7％,不形成花粉囊和花粉粒,属于无花粉囊型败育;另外33.3％的败育花药可形成花粉囊,小孢子均受阻于单核靠边期或者二胞期,败育特点为绒毡层细胞异常肥大,挤压小孢子,导致小孢子和绒毡层解体;6w-9605A的不育性稳定、彻底,不育株率和不育度均为100％.     

大白菜雄性不育系88—3花药和花粉发育的细胞形态学观察

大白菜雄怀不育两用系88－3的不育株,其开花时花药内无花粉粒,败育从小孢子母细胞至二核花粉粒皆有发生,高峰期在末期Ⅱ前后,小孢子母细胞不能进入减数分裂和小孢子母细胞不能完成减数分裂及孢子不能正常发育是雄性败育的主要形式;败育一旦发生便是急剧而彻底地解体或凝聚成一团是败育的共同点,中层组织、绒毡层组织及药隔维管束异常均是雄性败育的因素。     

芝麻核雄性不育系ms86-1微粉发生的细胞学观察

芝麻(Sesamum indicum)核雄性不育系ms86-1姊妹交后代表现为可育、部分不育(即微粉)及完全不育(简称不育)3种类型。不同育性类型的花药及花粉粒形态差异明显。Alexander染色实验显示微粉植株花粉粒外壁为蓝绿色, 内部为不均一洋红色, 与可育株及不育株花粉粒的染色特征均不相同。为探明芝麻微粉发生机理, 在电子显微镜下比较观察了可育、微粉、不育类型的小孢子发育过程。结果表明, 可育株小孢子母细胞减数分裂时期代谢旺盛, 胞质中出现大量脂质小球; 四分体时期绒毡层细胞开始降解, 单核小孢子时期开始出现乌氏体, 成熟花粉时期花粉囊腔内及花粉粒周围分布着大量乌氏体, 花粉粒外壁有11–13个棱状凸起, 表面存在大量基粒棒, 形成紧密的覆盖层。不育株小孢子发育异常显现于减数分裂时期, 此时胞质中无脂质小球出现, 细胞壁开始积累胼胝质; 四分体时期绒毡层细胞未见降解; 单核小孢子时期无乌氏体出现; 成熟花粉时期花粉囊腔中未发现正常的乌氏体, 存在大量空瘪的败育小孢子, 外壁积累胼胝质, 缺乏基粒棒。微粉株小孢子在减数分裂时期可见胞质内有大量脂质小球, 四分体时期部分绒毡层发生变形, 单核小孢子时期有部分绒毡层开始降解; 绒毡层细胞降解滞后为少量发育进程迟缓的小孢子提供了营养物质, 部分小孢子发育为正常花粉粒; 这些花粉粒比较饱满, 表面有少量颗粒状突起, 但未能形成覆盖层, 花粉囊腔中及小孢子周围存在少量的乌氏体。小孢子形成的育性类型与绒毡层降解是否正常有关。     

大果白刺雄性不育系的细胞学研究

利用石蜡切片法对大果白刺花药进行细胞学研究,探讨雄性不育系发生败育的时期和方式以及雄性败育与药壁组织间的关系.结果表明:不育系小孢子母细胞形成前期,花药各部分结构发育正常.随着绒毡层的异常解体,多种异常现象相继出现,包括小孢子母细胞液泡化,中层、药室内壁、药隔细胞液泡化,细胞畸形,药壁细胞非正常解体等.退化后整个花药萎缩干瘪,不能开裂,无花粉.因此,大果白刺雄性不育系的绒毡层生理异常并提前退化是导致雄性不育的主要原因.     

红菜薹雄性不育系花药败育的细胞形态学观察

采用石蜡切片技术,在光学显微镜下系统研究了红菜薹(Brassica campestris L.ssp．chinensis L.var．utilis TsenetLee．)波里马胞质雄性不育系(Polima CMS)、红菜薹萝卜胞质雄性不育系(Ogura CMS)及相应保持系花药发育过程的细胞形态学特征。观察结果表明：红菜薹Polima CMS花药发育受阻于孢原细胞阶段,不形成花粉,属无花粉型,此不育系花药不形成绒毡层和中层;而红菜薹Ogura CMS花药败育发生于小孢子母细胞期或四分体时期,表现为绒毡层细胞异常,挤压四分体,导致四分体和绒毡层同时解体而败育。     

羽叶薰衣草雄性不育的细胞学研究

用光镜和电镜观察羽叶薰衣草(Lavandula pinnata L.)雄性不育小孢子发育过程的细胞形态学特征.结果表明:羽叶薰衣草花药4枚,每枚花药通常具4个小孢子囊.花药壁发育为双子叶型,从外向内分为表皮、药室内壁、中层和绒毡层4层细胞.减数分裂形成的四分体为四面体及十字交叉型.小孢子的发育过程可分为造孢细胞期、减数分裂时期、小孢子发育早期、小孢子发育晚期.未观察到二胞花粉期和成熟花粉期.羽叶薰衣草花粉败育主要发生在单核花粉时期,细胞内物质解体并逐渐消失变成空壳花粉或花粉皱缩变形成为各种畸形的败育花粉.在此之前小孢子的发育正常.羽叶薰衣草小孢子不育机制体现在绒毡层过早解体、四分体时期以后各细胞中线粒体结构不正常、胼胝质壁与小孢子母细胞脱离、花药壁细胞中淀粉出现时间异常等. 壁发育为双子叶型,从外向内分为表皮、药室内壁、中层和绒毡层4层细胞.减数分裂形成的四分体为四面体及十字交叉型.小孢子的发育过程可分为造孢细胞期、减数分裂时期、小孢子发育早期、小孢子发育晚期.未观察到二胞花粉期和成熟花粉期.羽叶薰衣草花粉败育主要发生在单核花粉时期,细胞内物质解体并逐渐消失变成空壳花粉或花粉皱缩变形成为各种畸形的败育花粉.在此 前小孢子的发育正常.羽叶薰衣草小孢子不育机制体现在绒毡层过早解体、四分体时期以后各细胞中线粒体结构不正常、胼胝质壁与小孢子母细胞脱离、花药壁细胞中淀粉出现时间异常等. 壁发育为双子叶型,从外向内分为表皮、药室内壁、中层和绒毡层4层细胞.减数分裂形成的四分体为四     

萝卜雄性不育系花药发育组织化学的初步研究

对萝卜（ＲａｐｈａｎｕｓｓａｔｉｖｕｓＬ．）２种雄性不育系及相应保持系花药发育过程进行组织化学研究,研究结果表明,２种不育花药组织化学变化与小孢子败育变化皆类似,不育系４７５Ａ的花药发育受阻于孢原细胞分化之前,此时花药时含少量蛋白质,核酸的较多淀粉粒。随着花粉的长大,不再含有蛋白质,核酸和淀粉粒,不育系春红Ａ的花药在四分体以前与可育系类似,含丰富蛋白质,核酸和多糖。在单核期绒毡层异常引起小孢子败育     

宁夏枸杞雄性不育材料小孢子发生的细胞形态学观察

采用常规显微制片法,在光学显微镜下观察了宁夏枸杞雄性不育材料'YX-1'与可育材料'宁杞1号'的小孢子发生过程和各时期的形态特征.结果表明:不育材料'YX-1'小孢子发育受阻于四分体时期,无法形成正常的单核花粉粒,败育的特征是四分体胼胝质壁不能适时降解,四分孢子在胼胝质壁内液泡化、核质收缩降解,绒毡层细胞异常肥大增生,推迟解体.压片结果表明,不育材料'YX-1'四分孢子形状不规则、空瘪、解体,败育比较彻底.     

新型光温敏小麦不育系337S的组织结构研究

普通小麦(Triticum aestivum)不育系337S是一种对短日低温、长日高温均敏感不育的新型光温敏雄性不育系。对经过短日低温、长日高温处理的不育系花药及其小孢子的形态和发育过程进行了观察,观察结果表明,不育系337S的花药异常短小,开花后花丝短,花药难外露。花药发育过程中中层组织发育紊乱,绒毡层提前解体,影响了花粉母细胞发育所需的营养供应,导致短日低温处理下的花粉母细胞减数分裂中期Ⅰ和长日高温处理下的花粉母细胞发育时期花粉母细胞发育异常,形成异常小孢子,造成败育。     

A COMPARATIVE LIGHT- AND ELECTRON-MICROSCOPIC STUDY OF MICROSPOROGENESIS IN MALE-FERTILE AND CYTOPLASMIC MALE-STERILE SUNFLOWER (HELIANTHUS ANNUUS)

Cytoplasmic male sterility (CMS) in sunflower anthers is compared with its normal (N) line by using light and electron microscopy. Degeneration and disintegration of CMS tapetum and microspore tetrads occur after meiosis II, resulting in sterility. At the onset of meiosis, the CMS tapetum enlarges radially and shows signs of disorganization of organelles and walls. The developing CMS meiocytes and tetrads of microspores do not show these abnormalities when compared with their N counterparts. The CMS microspore tetrads remain viable until a rudimentary exine forms around each microspore. At this time, the radially enlarged tapetum disintegrates, followed by disintegration of the tetrads. In N-line microsporogenesis, a peripheral, dense tapetum is present at the tetrad stage, and as each locule enlarges, free spaces occur around the tetrads. After a rudimentary exine with associated spines and colpi is formed around each microspore, the callose holding each tetrad together dissolves, freeing the microspores for further development. Eventually the binucleate tapetum becomes plasmodial, persisting until the vacuolate pollen stage.     

Characterization and mapping of a male-sterility mutant, tapetum desquamation (t), in rice.

A spontaneously mutated male-sterile material was found among the offspring of the indica restorer line Jinhuiyihao. To understand the status and function of the related gene and clone the gene, a near-isogenic line (NIL) of the male sterility was bred, and characterization of the mutant and gene mapping were performed. The results indicated that there are obvious differences between the male-sterile NIL and the indica maintainer line II-32B. The anther size of the NIL is smaller than that of II-32B, and the anther color is white in the NIL but yellow in II-32B. No pollen from the matured anther in the NIL was observed to be stained using KI-I2 solution. In transverse sections of the sterile anther, at early microspore stage the cytoplasm of the tapetum concentrates but the tapetum itself does not degenerate after microspores are released from the tetrads; the tapetum then desquamates from the anther wall and enwraps microspores; subsequently, the surrounded microspores collapse completely at late microspore and early bicellular pollen stages. Inheritance analysis showed that the male sterility was controlled by a single recessive gene, ostd (t). This gene was mapped between the SSR markers RM7434 and RM275 on chromosome 6, and the physical distance from RM7434 to RM275 is about 389 kb.     

鱼腥草的花粉活力及雌雄配子体的发育

为深入了解鱼腥草有性繁殖特性及为鱼腥草杂交育种提供理论依据,以栽培的三年生鱼腥草（Houttuynia cordataThunb.）为材料,采用I2-KI染色法、培养基培养法、荧光显微镜观察法研究鱼腥草花粉活力;用石蜡切片法观察鱼腥草雌雄配子体的发育过程。结果显示,鱼腥草花粉活力极低,仅I2-KI法检测出鱼腥草花粉活力为3.18%,培养基培养法、荧光显微镜观察法均未测出花粉活力。其雄配子体在早期发育正常,但在二分体时期发现绒毡层解体,最后游离小孢子细胞质逐渐消失,显示出空瘪状态,形状也由近圆形变为不规则形,最终在花粉囊开裂之前小孢子败育。雌蕊心皮3枚,合生成一室,侧膜胎座;直生胚珠,为双层珠被,薄珠心;造孢细胞起源于紧接表皮之下的珠心细胞,造孢细胞直接发育成大孢子母细胞;大孢子母细胞经减数分裂形成线形或T形排列的四分体,靠近合点端的一个四分体细胞形成功能大孢子;功能大孢子经连续3次有丝分裂形成7细胞8核的蓼型成熟胚囊。鱼腥草可能因绒毡层提早解体导致雄性不育,其种子的产生可能来自于无融合生殖。     

长春蒲公英雄性不育株形态学观察与败育细胞学研究

在长春蒲公英(Taraxacum junpeianum Kitam.)株群中发现雄性不育现象,为研究其败育机理及特点,探寻其不育基因,采用形态观察法、石蜡切片技术和染色体压片法,对长春蒲公英野生型及其雄性不育株的花药发育过程和花粉母细胞减数分裂过程进行了观察。结果表明:(1)长春蒲公英雄性不育株花药中部发红、干瘪、无花粉散出。与野生型比较,雄性不育株雄蕊更短,子房更窄,种子形态更加狭长;(2)长春蒲公英雄性不育株败育时期为四分体到单核小孢子前期,败育方式为小孢子自身异常发育,绒毡层异常分解,互相粘连败育;(3)长春蒲公英雄性不育株花粉母细胞减数分裂二分体时期出现落后微核,随后产生极少四分体,并且四分体产生大量染色体桥,小孢子营养物质流失,彻底败育。因此,长春蒲公英雄性不育株败育彻底、稳定,并且有种的特点。小孢子自身异常发育和绒毡层异常分解是导致败育的主要原因。     

陆地棉双隐性核雄性不育系ms5ms6花药的超微结构观察

陆地棉双隐性核雄性不育系ms₅ms₆已有较大的应用规模,但雄蕊败育的结构基础尚不明确。以核雄性不育系ms₅ms₆为材料,利用透射电镜对四分体时期和刚长出小刺突的小孢子时期的花药进行超微结构观察。发现在小孢子时期,败育花药小孢子只有外壁内层,可育小孢子此时已具有外壁外层和外壁内层了。在整个不育花药的发育过程中,不管是在小孢子还是绒毡层细胞中,内质网都异常,脂肪的积累少,这可能是导致小孢子败育最重要的原因。     

Cytological and ultra-structural study on microsporogenesis of cytoplasmic male sterility in <Emphasis Type="Italic">Raphanus sativus</Emphasis>

The cytological development of microspores and tapetum in cytoplasmic male sterile (CMS) line A₁₄ and its maintainer B₁₄ in radish were studied using light- and transmission electron microscopy (LM and TEM). The microspores of the CMS line began to abort soon after they were released from tetrads in pollen sacs with light microscopy investigation, while abnormal behavior of pollen mother cells (PMC) were observed during its meiotic stage in its ultra-structural study, including degeneration of organelles and irregularity of nuclear membrane. At the same time, development of tapetal cells was similar to that of the maintainer. With further development of the anther, the tapetal cells of CMS line showed an abnormal increase in size and other appearances, such as fewer organelles and indistinct cytoplasm. The microspores of the CMS line were always distinguishable from the maintainer line with irregular structure, more osphilic deposits and abnormal exine. It is inferred that abortion of microspores is attributed to mutation of genes controlling male sterility, which further leads to hypertrophy of tapetum and destruction of ultra-structure.     

A Comparative Study of Anther and Pollen Development in Male Fertile and Male. Sterile Green Onion (Allium fistulosum L.)

Anther and pollen development in male-fertile and male-sterile green onions was studied. In the male-fertile line, both meiotic microspore mother ceils and tetrads have a callose wall. Mature pollen grains are 2-celled. The elongated generative cell with two bended ends displays a PAS positive cell wall. The tapetum has the character of both secretory and invasive types. From microspore stage onwards, many oil bodies or masses accumulate in the cytoplasm of the tapetal cells. The tapetum degenerates at middle 2-celled pollen stage. In male-sterile line, meiosis in microspore mother cells proceeds normally to form the tetrads. Pollen abortion occurs at microspore with vacuole stage. Two types of pollen abortion were observed. In type I, the protoplasts of the microspores contract and gradually disintegrate. At the same time the cytoplasm of microspores accumulates oil bodies which remain in the empty pollen. The tapetal cells behave normally up to the microspore stage and early stage of microspore abortion, but contain fewer oil bodies or masses than those in the male-fertilt line. At late stage of microspore abortion, three forms of the tapetal ceils can be observed: (1) the tapetal cells with degenerating protoplasts become flattened, (2) the tapetal cells enlarge but protoplasts retractor, (3) the cells break down and tile middle layer enlarges. In type Ⅱ, the cytoplasm degenerates earlier than the nucleus of the microspores and no protoplast is found in the anther locule. There are fibrous thickenings iii the endothecium of both types. It is difficult to verify whether the tapetum behavior and pollen abortion is the cause or the effect.     

云南紫稻细胞质雄性不育系花药发育过程中Ca2+的分布特点

运用焦锑酸钾沉淀法研究了云南紫稻细胞质雄性不育系和保持系花药在发育过程中Ca^2 的分布特点。结果表明,保持系的花粉母细胞和小孢子的胞质内部基本无Ca^2 的沉淀,后期花粉外壁出现Ca^2 的沉淀;保持系早期的绒毡层细胞形态正常,胞内有少量Ca^2 沉淀,后期绒毡层细胞开始凋亡,胞质凝集,胞内出现大量Ca^2 的颗粒。不育系花粉母细胞在减数分裂时期败育,胞质液泡化,内部出现大量Ca^2 的沉淀;不育系绒毡层细胞形态正常,胞内无Ca^2 的沉淀。绒毡层与花粉母细胞、小孢子之间出现大量Ca^2 颗粒。探讨了不育系花药花粉母细胞中以及与绒毡层细胞之间Ca^2 的异常积累与雄性不育的关系。     

辣椒雄性不育材料小孢子发生的细胞形态学观察

用石蜡切片技术,在光学显微镜下观察了辣椒雄性不育材料1A及其保持系1B的小孢子发育过程和各时期的形态特征.结果表明,雄性不育材料1A的小孢子败育发生在四分体至单核花粉粒时期,此时绒毡层细胞异常肥大,四分体受到挤压后破裂并降解,无法形成正常的单核花粉粒.扫描电镜观察结果表明,保持系1B的花粉粒结构完整,表面有3个明显的萌发沟;而雄性不育材料1A的成熟花粉粒形状不规则,空瘪,有部分花粉粒解体,败育比较彻底,说明该雄性不育材料在辣椒育种工作中有较高的利用价值.