部分中国传统月季花粉形态研究

利用扫描电镜观察了15个中国传统月季品种的花粉形态。结果表明:传统月季花粉为单粒花粉,呈长球形或超长球形（P/E为1.92～2.25）,大小为37.59～51.95 μm×17.02～25.33 μm。赤道面观椭圆形或长矩形,极面观三裂圆形,具三孔沟,沿极轴方向等间距环状分布。外壁纹饰条纹型,覆盖层具穿孔,在品种间具有相似性,但变异丰富,划分为4种类型。聚类分析结果表明,花粉大小和外壁纹饰特征在反映传统月季品种的类别上与形态分类基本一致。根据花粉形态演变规律可推断,样品中‘四面镜’可能为最原始的品种类型,‘月月粉’、‘月月红’及‘匍匐红’等品种较为进化。     

15个小苍兰品种的花粉形态研究

以15个小苍兰品种为试材,利用场发射扫描电镜（SET）对其进花粉形态观察,通过对花粉形状、大小、外壁纹饰及萌发器官等特征,分析不同品种间花粉形态之间的异同。结果表明：15个小苍兰品种的花粉均呈单粒存在且两侧对称,具远极单沟萌发孔,花粉外部形态均呈椭球形,极面观为舟形或心形,赤道面观除Castor外均为超长球形。花粉外壁纹饰均有小刺状凸起,多数品种表面有小穿孔和圆形斑纹。进一步聚类分析表明,15个小苍兰品种根据花粉形态特征可以分成3大类。本文首次报道了小苍兰的花粉形态,并且发现,不同品种间花粉形态特征具有一定差异,尤其是外壁纹饰细部特征和萌发器官的差别,体现了不同小苍兰品种间存在一定的遗传多样性和遗传分化,可为今后分析品种间亲缘关系及种质创新等提供有价值的科学依据。     

5种新疆苹果资源的果实品质性状比较与评价

选择5种果皮和果肉颜色不同的新疆苹果地方特色资源克孜阿尔玛、卡拉阿尔玛、阿克阿尔玛、伊犁野苹果、柠檬海棠,以栽培品种富士为对照,通过果实外观品质、内在品质、营养品质和香气品质4个方面的指标进行品质精细化评价,并考察了红肉苹果果肉花青苷合成途径相关基因的表达情况,以明确新疆苹果地方资源不同果实品质指标的差异,为新疆苹果地方资源的合理利用提供资料。结果表明:(1)5种特色资源均为中、小果型苹果,其中红肉品种克孜阿尔玛的外观品质优于栽培品种富士,而柠檬海棠外观品质指标均处于最低水平。(2)阿克阿尔玛的糖、酸含量均显著低于富士,柠檬海棠的酸含量高于富士及其他品种。(3)伊犁野苹果的果肉硬度显著高于富士,而红肉资源品种的果肉硬度均低于富士,肉质松软、不耐储运,但其总酚、类黄酮含量最为丰富,抗氧化能力最强,均显著高于栽培品种富士。(4)香气品质中,红皮资源卡拉阿尔玛的挥发性物质种类及含量最为丰富,其含量高于最低的栽培品种富士近2倍,红肉资源的挥发性物质含量最低;红肉资源的挥发性物质以醇类为主,而红皮资源卡拉阿尔玛、伊犁野苹果和柠檬海棠以醛类物质为主。(5)主成分分析显示,各个新疆苹果地方资源营养、香气品质等综合品质表现为:克孜阿尔玛卡拉阿尔玛阿克阿尔玛富士伊犁野苹果柠檬海棠。(6)红肉苹果的果肉花青苷合成途径相关基因表达分析表明,其果肉花青苷积累过程中的关键基因是UFGT。     

新疆胡颓子属三种植物的花粉形态及其分类学意义

该文采用主成分分析和聚类分析方法,运用扫描电镜对新疆胡颓子属(Elaeagnus Linn.)落叶组大果沙(E. moorcroftii)、尖果沙枣(E. oxycarpa)和沙枣(E. angustifolia)共计18个样品的花粉形态进行了观察和研究;全面描述了新疆胡颓子属3个种花粉的极轴长、赤道轴长、极面观、赤道面观、孔沟形态和外壁纹饰等形态特点,并对其进行数据分析,通过对聚类结果的比较,讨论不同孢粉学特征对分类结果的影响。结果表明：(1)3个种的花粉均为中等大小;萌发孔类型均为三孔沟型。(2)花粉极面观形状从三角形、钝三角形到圆三角形;赤道面观形状从菱角形、半圆形到扁圆形;外壁纹饰从皱波状到穴状。(3)以筛选出的5个反映花粉形态的主成分指标进行聚类,结果显示所选指标不能区分种;以代表花粉形态的极面观形态和赤道面观形态为指标进行聚类同样也无法区分3个种;以花粉粒大小为指标进行聚类发现,大果沙枣的花粉大小可以区别于其他2个种。研究表明除了大果沙枣花粉的大小,尖果沙枣和沙枣的花粉形态不宜直接应用于种的划分。该研究结果为新疆胡颓子属落叶组植物花粉的种间鉴定和品种划分以及进化关系的研究提供了孢粉学依据。     

抗风桐(Pisonia grandis)的生态生物学特征

对收集于广西桂林的17份野生毛葡萄种质和24份栽培葡萄种质,分别使用12条ISSR和12条SCoT引物进行了遗传多样性和亲缘关系检测。结果表明：两种分子标记均能产生较丰富的多态性片段,可有效应用于葡萄的遗传多样性检测,但在聚类分析结果上表现出一定的差异性,SCoT分子标记能更好地区分野生种质和栽培品种,说明SCoT分子标记在葡萄遗传多样性检测和系统进化研究上可能更有优势。从SCoT聚类结果上看,广西植物研究所收集的3个野生毛葡萄种质zws1、zws2和zws3相对其它野生种质而言,更偏向于与栽培种质聚为一类,说明这一类野生毛葡萄可能是这些栽培品种的原始亲本来源之一。不同的野生种质聚为多个类群,并表现出明显的地域特性,但遗传距离相对较远,说明桂林野生毛葡萄资源具有丰富的遗传变异。栽培品种没有明显的聚类特点,可能因为所选用的栽培品种的地域代表性并不是很强,也可能是因为栽培品种在不断的人工杂交选育过程中,遗传背景趋向一致,遗传多样性降低。该研究证明SCoT分子标记在葡萄遗传多样性研究上具有一定的优势。该研究结果为桂林毛葡萄资源的保护、利用和品种选育提供了理论依据,也为葡萄的系统进化研究提供了参考。     

41份葡萄种质遗传多样性的ISSR和SCoT对比分析

对收集于广西桂林的17份野生毛葡萄种质和24份栽培葡萄种质,分别使用12条ISSR和12条SCoT引物进行了遗传多样性和亲缘关系检测。结果表明:两种分子标记均能产生较丰富的多态性片段,可有效应用于葡萄的遗传多样性检测,但在聚类分析结果上表现出一定的差异性,SCoT分子标记能更好地区分野生种质和栽培品种,说明SCoT分子标记在葡萄遗传多样性检测和系统进化研究上可能更有优势。从SCoT聚类结果上看,广西植物研究所收集的3个野生毛葡萄种质zws1、zws2和zws3相对其它野生种质而言,更偏向于与栽培种质聚为一类,说明这一类野生毛葡萄可能是这些栽培品种的原始亲本来源之一。不同的野生种质聚为多个类群,并表现出明显的地域特性,但遗传距离相对较远,说明桂林野生毛葡萄资源具有丰富的遗传变异。栽培品种没有明显的聚类特点,可能因为所选用的栽培品种的地域代表性并不是很强,也可能是因为栽培品种在不断的人工杂交选育过程中,遗传背景趋向一致,遗传多样性降低。该研究证明SCoT分子标记在葡萄遗传多样性研究上具有一定的优势。该研究结果为桂林毛葡萄资源的保护、利用和品种选育提供了理论依据,也为葡萄的系统进化研究提供了参考。     

不同秋眠性苜蓿的遗传多样性研究

苜蓿的秋眠性是苜蓿引种,栽培的依据。采用RAPD技术对32份不同秋眠性苜蓿进行遗传多样性和系统发育研究。结果表明,13条引物共扩增出217个标记,有214个多态位点,多态频率达到98．6％,说明这些苜蓿品种具有很高的遗传多样性。聚类分析表明,安徽野生南苜蓿和其它栽培品种苜蓿有大的遗传差异,单独聚为一类。其余31个品种在相似系数为0．815的地方聚为4类,并且,相对秋眠性强的苜蓿品种的遗传基础更为丰富,而秋眠级数低的苜蓿品种相对遗传基础较狭窄。本研究同时表明,安徽野生苜蓿将能够为南方苜蓿育种丰富遗传基础,应加大保护和研究。     

新疆野苹果(Malus sieversii(Ledeb.) M.Roem.)植物学性状遗传多样性及相关性分析

为加强野苹果种质资源利用与研究,促进野苹果研究工作,以3年来调查收集的新疆野苹果(赛威士苹果)的129个单株资源为材料,对单果重、果实纵横经、叶片大小等12个数量性状和叶片颜色、叶尖类型等5个质量性状进行遗传多样性及相关性分析。分析结果表明:叶片颜色、叶尖类型、叶姿、叶缘、叶面状态5个质量性状分布频率较集中;单果重、果实纵横经、叶柄长、叶片长宽、可溶性固形物、干周、树高均存在较大变异,变异系数幅度为16%~51%。各性状多样性指数也较大,均值为1.9264,叶片长的多样性指数最小为1.7359;果梗长的多样性指数最大为2.0525。新疆野苹果资源拥有丰富的遗传多样性,在于果实相关性状的多样性指数高,且变异幅度大,表明丰富的遗传多样性是新疆野苹果资源的重要特征。     

不同品种烟草花粉电子显微镜观察

通过对10个烤烟品种、8个晒烟品种、2个野生种的花粉进行扫描电子显微镜观察,发现同为烤烟或晒烟的烟草,其花粉的形态、大小、外壁纹饰比较稳定。野生烟在供试种中具有独特的细网状外壁纹饰,是鉴别野生烟与非野生烟的一条有效途径。     

塞威氏苹果Malus sieversii（Ldb.）Roem花粉形态的研究

对采自75个不同居群的塞威氏苹果（Malus sieversii (Ldb.)Roem）的花粉形态进行了观察。结果表明：塞威氏苹果花粉萌发孔为三孔沟类型,外壁具条纹状纹饰,条纹间常具小穴或穿孔。根据外壁纹饰的差异将塞威氏苹果花粉划分为六个类型。同时根据花粉资料,探讨了塞威氏苹果的某些分类学和系统学问题。     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418     

Separation of the pineal vesicle from the wall of the third ventricle during the post-hatching development of the chicken

Summary According to light- and electron-microscopic observations the pineal organ of the 3-day-old chicken consists of a prominent end vesicle and a tapering parenchymal stalk. During this stage the pineal lumen is in open communication with the third ventricle. However, in the 40-day-old chicken, which still possesses a well-developed end vesicle, the proximal portion of the pineal stalk displays regressive changes leading to local fragmentation. At this stage the pineal stalk is reduced, and the pineal lumen is missing. In 1-year-old chickens the parenchyma of the proximal portion of the stalk is further diminished, and in 3-year-old domestic fowl is completely displaced by bundles of collagenous fibers, only some nerve fibers being present. This post-hatching pineal development may reflect the sequence of changes leading from pineal sense organs to pineal glands.This work was supported by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan