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野豌豆属牧草适宜在高寒和高海拔地区栽培,是我国高原牧区重要的蛋白饲料来源。该属有190个物种,4个亚属:Vicia,Cracca,Ervum和Faba。本研究从中国、美国、土耳其和叙利亚等11个国家收集了16份野豌豆属牧草种质,利用扫描电镜对这16份材料的花粉形态进行观察。结果表明,野豌豆属植物花粉均以单粒形式存在,极面观为三裂圆形和三角形,赤道面观为扁圆形、长椭圆形和椭圆形。三沟萌发孔,沟长深入两端;极轴长为(9.60±1.52)(30.40±2.07) μm,赤道轴长为(11.80±0.84)(38.20±0.84) μm。花粉的表面纹饰呈3种类型:网状纹饰,脑状纹饰和疣状纹饰。网状纹饰根据外壁纹饰疏松程度不同,又可分为2种亚类型:粗网状纹饰和细网状纹饰。本研究较为系统地观察了16个野豌豆属牧草的花粉形态,探讨了其系统分类学特性,为揭示野豌豆属种质资源的遗传多样性奠定了基础。 相似文献
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应用扫描电镜对卫星搭载的2个紫花苜蓿(Medicago sativa L.)品种的花粉显微结构进行了观察研究.结果表明:花粉为长球形和近球形2种,赤道面观为椭圆形,极面观为三裂圆形,具3(拟)孔沟,沟为条形,狭缝状,沟长至两极,孔处有外突或无;花粉外壁纹饰为穴状、粗糙状、网状3种;花粉的外壁纹饰不同品种间以及同一品种的不同处理间均有差异.这2个紫花苜蓿品种的花粉形状、大小和外壁纹饰与地面对照对应品种的花粉存在显著差异(P<0.05),表明空间飞行因子可导致花粉发育异常及可遗传突变等诱变效应.卫星搭载的2个品种存在花粉败育,不同品种间败育花粉数量存在差异.败育花粉粒形状干瘪,外形异常. 相似文献
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采用扫描电镜(SEM),对内蒙古阿拉善荒漠区10种特有植物的花粉形态进行了详细的观察描述,掌握了它们在扫描电镜水平上的形状、大小、表面纹饰、萌发器官类型及数量等形态特征,为生态建设、环境保护、地质地貌、植物分类及遗传育种等相关研究提供了可靠的孢粉学参考。 相似文献
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为了解猕猴桃属植物间的亲缘关系,以41份不同猕猴桃花粉为供试材料,采用扫描电镜对猕猴桃花粉进行形态学观察和分析,选取6个性状指标进行测量,根据观测结果对供试材料进行聚类分析。结果表明:供试花粉均为单粒花粉,均以单粒、等极和辐射对称形式存在。极轴长度范围在21.50~33.40μm之间,赤道轴长度范围在9.87~16.24μm之间,萌发沟长度范围在17.53~29.08μm之间,萌发沟脊宽度范围在0.47~2.03μm之间,花粉粒大小(极轴×赤道轴))范围在218.68~543.18μm2之间,极轴长度与赤道轴长度比值范围为1.36~2.26,花粉形状为超长球形或长球形,萌发孔类型均为三孔沟,极面观为三裂圆形,均为N3P4C5型。外壁纹饰为波纹状、颗粒状、疣状三种类型,占样品总数的比例分别为63.41%、19.51%、17.08%。在遗传距离为7.5时,供试材料可以分为3个类群,在遗传距离为1.5时,供试材料可以分为6个类群。 相似文献
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触角作为蜜蜂重要的感觉器官,在感受外界环境刺激、实现个体间信息交流方面具有重要意义。中华蜜蜂是我国本土蜂种,亦是一类经济昆虫。本研究采用扫描电镜技术对中华蜜蜂工蜂与雄蜂触角及其表面感受器的形态和分布进行分析。结果表明,中蜂触角呈膝状,包括柄节、梗节和鞭节3部分。工蜂柄节比雄蜂的修长,而雄蜂鞭节较工蜂的粗壮,且多一节。工蜂触角上有7种类型的感器,其中毛形感器分布最多,雄蜂触角上有6种感器,其中板形感器分布最多。在雄蜂触角上发现了一类新的感器为栓锥形感器。工蜂和雄蜂触角的差异不仅表现在形态和触角节数上,其感受器的种类、数量和分布也存在明显差异。 相似文献
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Endothelial cell function is essential to maintain corneal transparency, but unfortunately the regenerative capacity of the endothelium is limited. There are only a few reports describing the effect of age on morphologic appearance of corneal endothelial cells of dogs. Studies of normal corneal endothelial cells in humans and dogs have shown a decrease in endothelial cell density (ECD) and an increase in pleomorphism and polymegethism with advancing age. The purpose of this study was to investigate the effect of age on ECD and endothelial cell morphology in dogs. A total of 30 dogs were divided into three groups (10 dogs/group) based on age: group 1 (2-12 months old), group 2 (24-72 months old), and group 3 (84 months or older). Corneas were processed for light and scanning electron microscopy. Results showed only difference in cell density between group 1 and groups 2 and 3, showing an initial decrease in cell density as the animal matured. Whereas there was significantly greater variation in cell size within the dogs in group 3 than there was within the other two groups, suggesting that there was increased polymegethism and pleomorphism with advancing age. 相似文献
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Lizette Du Plessis Erna Van Wilpe 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):316-320
Background: The important role of thrombocytes in hemostasis is well documented, but little information is available on the thrombocyte morphology of avian species, including vultures. Objective: The objective of this study was to describe and compare the morphology and morphometric parameters of thrombocytes in 2 vulture species. Methods: Blood samples were collected into tubes containing acid‐citrate‐dextrose from 5 Cape vultures (Gyps coprotheres) and 6 white‐backed vultures (Gyps africanus) at the De Wildt Breeding Center, Northwest Province, South Africa. Wright's‐stained blood smears were examined by light microscopy. Samples were processed and examined by scanning and transmission electron microscopy (TEM) using standard techniques. Morphometric parameters (perimeter, area, minimum and maximum diameter, and aspect ratio) were measured on 140 thrombocytes using imaging software. Results: Thrombocytes were predominantly oval to elliptical, with few pseudopodia. The nucleus was the most prominent feature of the cells. Large vacuoles were visible in the cytoplasm by both light and TEM. Ultrastructurally, microtubules and dense bodies were seen in most cells. Other cytoplasmic organelles seen by electron microscopy included mitochondria, endoplasmic reticulum, a surface connecting canalicular system, Golgi complex, lipid droplets, and glycogen. Thrombocytes of Cape vultures had a significantly (P=.005) higher aspect ratio compared with white‐backed vultures. Thrombocyte estimates in blood smears were similar in both species, with a combined mean of 31.6 × 109/L. Conclusion: The morphologic features of thrombocytes in southern African vultures are similar in most ways to those of other avian species. Although thrombocytes in white‐backed vultures were slightly more spherical than those of Cape vultures, no other significant differences were found between the 2 species. 相似文献
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运用扫描电镜观察了中间偃麦草Elytrigia intermedia和长穗偃麦草E. elongata的根、茎、叶以及根茎的形态解剖结构,结果显示:2种植物的根形态均由表皮、皮层和中柱组成,表皮着生大量根毛,内皮层细胞壁5面加厚,在横切面上呈马蹄形;茎与根茎的维管束分内外两圈分布,中央有髓腔;叶片形态由表皮、叶肉和叶脉3部分构成,表皮细胞包括长细胞、附属物、气孔器细胞和泡状细胞。中间偃麦草和长穗偃麦草的叶片表皮微形态上存在显著差异,其中长穗偃麦草叶脉上分布3~4列乳突,而中间偃麦草叶脉上则分布3~4列刺毛,另外在根皮层细胞中发现了发达的类似通气组织的结构,产生原因亟待进一步研究。 相似文献
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为探究鹅个体发育过程中小肠绒毛形态发育情况,通过扫描电子显微镜对鹅胚胎发育过程中和成体的小肠绒毛进行形态学观察。结果表明:鹅胚胎时期,小肠绒毛经历了由山脊状黏膜褶发育为“W”形板状黏膜嵴最后变为指状绒毛的过程;出雏后,鹅小肠绒毛形态由指状变回板状。其中,鹅胚胎发育18 d后(胚胎发育的60%阶段后),小肠表面黏膜由山脊状黏膜褶变为规则的“W”形板状黏膜嵴。发育25 d后(胚胎发育的83.3%阶段后),板状黏膜嵴均变为指状绒毛。鹅胚孵出8 d后小肠指状绒毛开始变扁,17 d龄鹅的小肠指状绒毛变成板状绒毛,成体鹅一直保持板状绒毛形态。 相似文献
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摘要:以密斯蒂蓝莓为试材,进行花粉粒电镜扫描及自花授粉和异花授粉试验,观察花粉管萌发及生长动态荧光显微,调查不同授粉方式的坐果率,测定果实品质。结果表明,密斯蒂花粉形态均为四合花粉,呈四面体排列,近似圆角三角形,极轴*赤道轴为28.5*26.02μm;荧光显微观察发现自花授粉和异花授粉8h花粉开始在柱头萌发,14h有大量花粉萌发,花粉管进入花柱;24h花粉管进到花柱底部;48h花粉管进入胚珠,到达胚囊,完成双受精,自花授粉和异花授粉均有较好的亲和性;密斯蒂异花授粉坐果率最高,两种授粉方式果实品质无显著差异。 相似文献