慈姑雌花在自然居群中的受粉过程：花粉粒落置,萌芽？…

用荧光显微术观察了慈姑不同时期的雌花柱头上花粉粒的落置１、萌发及花粉管的生长过程与途径。结果表明：该种雌花开花２ｈ柱头受粉率为０，开花４ｈ和８ｈ受偻率分别为５３．８％和９８．３％，柱头上花粉萌发这１００％；花粉管沿雌蕊之向心一侧的组织中穿行至子房基部后部分花粉管转向胚球，由珠孔进入珠心。本研究发现 花粉管常过子房基部至花托组织，并可进入其他蕊中，作者认为这种行为可能对保证雌花的结实率有一定意义。     

矮慈姑人工授粉后花粉管生长的荧光显微观察

用荧光显微术观察了矮慈姑人工授粉后雌蕊上花粉粒萌发及花粉管的生长过程与途径,结果表明：该种在授粉０．５ｈ后花粉粒全部萌发出花粉管,花粉管在授粉２ｈ后部分到达子房,４ｈ仙进入胚珠;花粉管在雌蕊之向心一侧的组织中行进,至子房基部后部分花部管转向胚珠,由珠孔进入珠心。     

楸树自交及种内、种间杂交亲和性的细胞学观察

运用荧光显微技术、整体透明法和石蜡切片法,对楸树自交及种内、种间杂交亲和性进行了显微观察.结果表明:无论自交或种内、种间杂交花粉均可在柱头萌发,但萌发时间和萌发率存在显著差异.花粉管在柱头分泌物中生长或穿透乳突细胞沿柱头中部维管束生长,之后进入花柱引导组织胞间隙.大量种内和种间杂交花粉管于授粉后12～24 h迅速生长至花柱基部；48 ～72 h进入子房；96～120 h前后发生双受精,肉眼可见子房发红膨大.自交授粉后约36％的花粉管在柱头和花柱上端终止生长；42％的花粉管于授粉后72～96 h进入子房；直到授粉后120 h花冠脱落为止,少数花粉管能够穿透胚囊,但未见双受精发生,子房无膨大.研究认为:楸树具有自交不亲和性,而种内和种间杂交是亲和的；其不亲和反应发生的最终位置在子房,时间在合子形成前,为合子前晚期自交不亲和类型.     

不同授粉方式对祝光苹果受精过程的影响

祝光苹果自花授粉后2小时,花粉粒在柱头上萌发。授粉当日和次日,花粉管在花柱中生长。授粉后第三日,花粉管停止生长,最长花粉管平均长至花柱全长的26％。此时,花粉管先端明显膨大。而后,未见到有抵达花柱基部的花粉管,也未见到受精过程的发生。 异花授粉后4—6小时,大量花粉粒在柱头上萌发。授粉后1—2日,花粉管径直向花柱基部生长。授粉后50小时,花粉管穿过花柱基部,进入子室内。授粉后3—4日,观察到进入胚囊的花粉管将内含物释放到一个已退化的助细胞中。授粉后5—6日,观察到双受精过程。     

陆地棉花粉粒萌发和花粉管生长特性

以陆地棉为材料,用苯胺蓝染色法对花粉管进行染色,观察棉花花粉粒在柱头上的萌发和花柱中花粉管的生长状况.授粉后,统计花柱中花粉管的数量,将花粉活力与花粉管数量直接联系起来,为棉花花粉活力测定和生殖过程的基本规律研究提供了新的方法.活体和雌蕊离体培养两种条件下,花粉原位萌发结果基本一致.活体原位萌发在授粉1h后.个别花粉开始萌发,4h后柱头上的花粉全部萌发,12h后大量的花粉管伸长到花柱基部.统计花柱中花粉管数量的准确时间应在授粉后4—12h.离体原位萌发各式各阶段均较活体原位萌发慢1h.可用离体原位萌发法代替活体原位萌发法测定花粉活力,活体和离体原位萌发两种情况下,花粉管的平均生长速度分别为0.03和0.29cm/h.花粉萌发及花粉管在花柱中生长的最适温度为30℃.花粉管在花柱中呈曲线方式生长.     

烟草花粉与雌蕊互作调控机制研究进展

授粉是植物生活史周期中的一个重要过程.茄科植物属于湿柱头,实心花柱.成功授粉起始于花粉粘附在成熟的柱头表面,接着水合、萌发,花粉管穿过柱头后沿着花柱传导组织细胞间隙朝着胚囊的方向生长,经过助细胞后释放精子完成双受精.在这个过程中,花粉外壁决定因子与花粉管生长通道中的各种成分相互作用,激活花粉管细胞内部的一系列生理生化反应.存在于烟草柱头、花柱传导组织细胞、子房和助细胞中的各种分泌物对于花粉细胞粘附、花粉管生长营养供给、信号传导、方向引导具有重要作用;另外,某些花粉决定因子与雌蕊成分的相互作用也可能导致自交不亲和与杂交不亲和.文章总结了烟草授粉后花粉与雌蕊相互作用涉及的物质及机理,这些物质主要包括蛋白质、多糖、脂类、激素、酶类和黄酮类等.     

植物中花粉管在柱头的生长特征

在多数高等植物中,花粉粒通过虫媒或(和)风媒到达植物雌花柱头,花粉粒在柱头吸水萌发后,穿过花柱组织,最终花粉管将两个精细胞传递给雌配子体,从而实现双受精作用.在受精过程中,花粉管必须穿透柱头并在花柱组织中生长,最后到达胚珠的珠囊,这一定向生长过程需要十分精确的调控.本文就花粉管的激活和引导研究进展进行了综述,并对今后的...     

鼠尾草属植物杂交亲和性探究

为研究鼠尾草(Salvia)不同品种间杂交亲和性,选取3种7个品种的鼠尾草作为试验材料,检测花粉活力及柱头可授性强弱,进而通过荧光观察杂交后花粉萌发和花粉管生长情况.结果表明,鼠尾草的花粉活力及柱头可授性均在开花后1～2 d内达到最大;不同种间相互授粉杂交亲和性普遍低于种内杂交,正反交结果也存在差异,出现萌发缓慢、花粉管畸形生长等现象,只有少量的花粉管进入花柱基部使子房膨大;种内杂交比种间杂交更容易得到有胚种子.为了更好地完成杂交育种工作,需选择正确的杂交亲本,在适宜时期进行人工授粉,能够有效提高杂交成功率.     

北美鹅掌楸和中国鹅掌楸种间杂交胚胎学

１．中国鹅掌楸花粉在北美鹅掌楸柱头上萌发良好，速度快且整齐。２．花粉管生长速度最早在８０ｈ进入胚囊，大多数在１２０ｈ以后。个别花粉管在花柱中顶端膨大、破裂，或行至珠孔发生扭曲现象。３．花粉管通过柱头沟和花柱道时生长快，通过珠孔塞和珠孔以及珠柄时生长缓慢。４．控制授粉后５ｄ左右发生双受精，合子休眠约２０ｄ左右，３０ｄ左右是球形胚，９０ｄ子叶胚形成；１４０ｄ胚分化完成，种子成熟。５．连续三年的结籽率调     

番红花不育现象的观察

通过对北京地区栽培的番红花生殖器官的观察,发现它的雌配子体发育正常,花粉能在柱头上萌发,只因花粉管不能伸入到花柱和子房而不能受精。     

海甘蓝与芸苔属属间杂交的亲和性研究

对海甘蓝和芸苔属属间杂交的花粉粒萌发，花粉管生长以及珠孔受精情况进行了研究。结果表明，甘蓝型油采与海甘蓝杂交不亲和，表现在花粉管不能进入柱头或不能通过珠孔肥精，同时乳突细胞有强烈的胼胝质反应。白菜型油菜与海甘蓝杂交有少量花粉管萌发，花粉管顶端受阻于柱头乳突细胞中缠绕于乳突细胞表面，乳突细胞有大量的胼胝质产生。     

不同贮藏温度对4种杨树花粉生活力的影响

采用花粉离体培养的方法对不同温度条件下贮藏的4个杨树无性系花粉活力进行了研究,并对超低温贮藏1年后杨树花粉用于杂交育种的可行性进行了研究。结果表明,杨树花粉在离体培养28 h萌发率达到最大。贮藏3个月后,-20℃贮藏条件下4个杨树无性系花粉的萌发率最高,分别是:白杨84 K为36%,白杨毛新杨×银灰杨为35.2%,中菏1号为39.2%,钻天杨为41.9%。-80℃贮藏1年后的花粉仍具有生活力,能够正常授粉并获得正常发育的种子。     

Actin and myosin during pollen germination

Actin and myosin from pollen tubes of Lilium davidii were studied by using immunoblotting, Dot_Blot and myosin Ca 2+_ATPase analysis. On immunoblotting of the total soluble pollen tube proteins, anti_α_actin antibody labelled a polypeptide approximately 43 ku, which is considered to be the actin of lily. The mRNA encoding actin in ungerminated pollen and germinated pollen were both undetectable in our experiments. A myosin exhibited Ca 2+_ATPase activity, with a native molecular weight of 460 ku has been identified by using immunoblotting. A polypeptide of about 205 ku and a polypeptide of about 20 ku were the heavy chain and a set of light chain of the myosin, which can crossreact with anti_skeletal muscle myosin heavy chain monoclonal antibody and anti_skeletal muscle myosin light chain (20 ku) monoclonal antibody, respectively. The Ca 2+_ATPase activities of myosin in crude extracts of germinated pollen were positively related to the growth rates of pollen tubes.     

Identification and function analysis of spectrin-like protein in pollen tubes of lily （Lilium davidii Duch）

The elongation of pollen tube is an important process of sexual reproduction in higher plant. Cytoskeleton plays a major regulatory role in the elongation of pollen tubes. But whether membrane skeleton is involved in the pollen tube elongation is not clear. In this study, immunochemical detection of spectrin-like protein has been carried out in pollen tubes. By use of 2-dimensional electrophoresis(2DE) and western blotting, two spectrin-like proteins are found, one is 150 kD, and the other is 105 kD, with pl being 4.54 and 4.39, respectively. 150 kD spectrin-like protein is located in plasma membrane of pollen tube and 105 kD spectrin-like protein is located in cytoplasm, probably functioning as a subunit to form a dimmer (210 kD) in vivo. The elongation of pollen tubes is inhibited after spectrin antibody was injected into a growing pollen tube. These results suggest that spectrin-like proteins exist in pollen tube and play an important regulating role in the elongation process of pollen tubes from lily.     

Primary measurement of pollen flow inLiriodendron chinense using RAPD markers

Techniques of tracking movements of pollen grains are essential for many topics in pollination biology. Pollen transfer ofLiriodendron chinense (Hemsl.) Sarg., a hermaphroditic plant, may be both interfloral and intrafloral pollination. Observations on pollinator movements and flower emasculated experiments in natural populations showed that most of pollen grains deposited on stigmas in a flower are foreign. But it is not certain whether cross pollination or long distance pollen transfer occurs in this insect-pollinated plant. The authors attempt to use random amplified polymorphic DNA (RAPD) loci for paternity analysis to mark pollen dispersal. The results indicated pollen via gene transportation reached at least 100 m away from the pollen source in a selected population. The primary study suggests a larger effective population size in this endangered plant. With its rapid and simple characters, RAPD methods can be a suitable technique for marking pollen flow and able to be widely used in various taxa.     

Distribution of a kinesinrelated protein on Golgi apparatus of tobacco pollen tubes

The conventional kinesin and kinesin-related proteins (KRPs) constitute a large family of microtubule-based molecular motors. Members of this family bind to micro-tubules in an ATP-dependent manner. They all have microtubule-activated ATPaes activities, and play essential roles in the transport of various vesicles and organelles in eukaryotic cells[1―3]. The first plant kinesin-like protein was detected in tobacco pollen tube with an antibody against animal kinesin[4]. Recently, a number …     

甘薯花粉—柱头乳突细胞间相互作用的细胞学研究

以甘薯鸟吃种和高自一号为亲本进行人工自花授粉;以甘薯鸟吃种和高自一号为母本,河北351为父本进行杂交授粉.观察了花粉在柱头上的行为,柱头乳突细胞表面糖蛋白的定位分布,授粉前后乳突细胞超微结构的变化.结果表明,不育组合首先表现出花粉在柱头上粘附和水合能力很弱,花粉不萌发.能育组合授粉后花粉在柱头上的粘附水合能力很强,多数花粉萌发.但有的花粉管不进入柱头,仅在乳突细胞表面爬行,或提前破裂,释放内容物;以及在花粉管接触的柱头乳突细胞中沉积胼胝质.糖蛋白(钉红着色物质)在能育与不育组合的柱头乳突细胞壁上的分布有明显的差异,作者用细胞化学定位法验证了糖蛋白与自交不育可能存在的相关性.鸟吃种柱头乳突细胞杂交授粉后12h其超微结构明显退化;而自花授粉后3h就已明显退化.柱头乳突细胞退化的早晚可能与所授花粉是否能育相关.     

Immunochemical identification of gelsolin in maize pollen

Gelsolin is a representative of a type of actin-binding proteins (ABPs) universally found in eukaryotes. It plays role in nucleation, capping and severing of actin filamentsin vitro. In our experiment, gelsolin was purified from pig plasma and the polyclonal antibodies against it were prepared. The crude extracts of maize pollen were immunodetected by Western-blotting with polyclonal antibody and monoclonal antibody respectively. The immunodetection results show that gelsolin exists in maize pollen and its molecular weight is about 91 ku, similar to that of gelsolin found in animal tissues.