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111.
该研究采用光学显微镜与扫描电子显微镜对山芹属(Ostericum Hoffm.)8种17个居群的花粉形态特征进行观察和分析,为山芹属分类鉴定与属下系统关系研究提供依据。结果显示:(1)山芹属17个居群的花粉类型包含椭圆形、近长方形、超长方形和赤道收缩形4种类型。(2)花粉赤道面观有近椭圆形、近长方形与超长方形,极面观多为三角圆形,少数为三角形。(3)花粉极轴长度为24.7~35.6 μm,赤道轴长度为10.6~17.4 μm,极轴与赤道轴的比值P/E为1.7~2.5,体积指数P×E1/2为18.2~22.6。(4)花粉萌发孔均具三孔沟,且多为边萌发孔,角萌发孔较少,沟细长且均匀。(5)花粉赤道区外壁纹饰分为3类,即片状脑纹、长条状脑纹和短棒状脑纹,少数具有颗粒状或疣状的附着物。研究认为,山芹属植物花粉的形状与赤道区外壁纹饰类型存在较高的种内一致性,萌发孔类型、花粉中部是否凸出以及纹饰条纹长度、密集程度、附属物等特征则存在一定的种内差异性;花粉形态特征可为山芹属植物不同层次的分类鉴定与亲缘关系研究提供重要的证据。 相似文献
112.
113.
Edward L. Vezey Varsha P. Shah John J. Skvarla 《Plant Systematics and Evolution》1992,181(3-4):245-254
We present a key synthesizing pollen-sculpture terminology for grains having perforations or lumina of any size and spatial distribution. The key uses quantitative criteria to distinguish five non-overlapping qualitative terms (reticulate, microreticulate, foveolate, scrobiculate, and punctate). In addition, the range of quantitative variation encompassed by these qualitative terms is highlighted, including ways to express and compare that variation using computerized image analysis of SEM micrographs. Finally, a mathematical analysis combined with image-analysis measurements is used to explore the relationships between the terms outlined above and two closely related terms, tectate and semitectate. 相似文献
114.
115.
Yuning Chen Shaolin Lei Zhengfu Zhou Fangqin Zeng Bin Yi Jing Wen Jinxiong Shen Chaozhi Ma Jinxing Tu Tingdong Fu 《Plant cell reports》2009,28(9):1363-1372
Male sterility in a near-isogenic line S45AB after 25 generations of subcrossing is controlled by two pairs of duplicate genes.
The genotype of S45A is Bnms1Bnms1Bnms2Bnms2, and that of S45B is BnMs1Bnms1Bnms2Bnms2, respectively. Histological observations revealed that abnormal anther development appeared in the tapetum and pollen exine
during the tetrad stage. This male sterility was characterized by hypertrophy of the tapetal cells at the tetrad stage and
a complete lack of microspore exine after the release of microspores from the tetrads. To elucidate the mechanism of this
recessive genic male sterility, the flower bud expression profiles of the S45A and S45B lines were analyzed using an Arabidopsis thaliana ATH1 oligonucleotide array. When compared with the S45B line, 69 genes were significantly downregulated, and 46 genes were
significantly upregulated in the S45A line. Real-time polymerase chain reaction (PCR) was then used to verify the results
of the microarray analysis, and the majority of the downregulated genes in the S45A line were abundantly and specifically
expressed in the anther. The results of the real-time PCR suggest that Bnms1 might be involved in the metabolism of lipid/fatty acids, and the homologous mutation of Bnms1 may either block the biosynthesis of sporopollenin or block sporopollenin from being deposited on the microspore surface,
thus, preventing pollen exine formation. The role of Bnms1 in the regulatory network of exine formation is also discussed as well.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
116.
Magda O. Weber-El Ghobary 《Plant Systematics and Evolution》1986,152(3-4):267-276
Light and SEM observations on the pollen ofDyerophytum africanum andD. indicum have revealed marked differences in exine features. These distylous species also have dimorphic pollen. In the short-styled individuals of both species, the sexine and nexine are of equal thickness, and the clava-like sexinous processes are short without marked projections. In the long-styled individuals, the sexine is thicker than the nexine, the clavae are higher than broad with an apical spinule. Pollen size and apertures are identical in both morphs. — Palynological evidence is presented for relationships betweenDyerophytum andCeratostigma, Plumbago andAegialitis. Moreover, the genusDyerophytum exhibits pollen morphological similarities with some species ofLinum (Linaceae). 相似文献
117.
The pollen morphology of 29 species ofOdontites and related genera was examined by light and scanning electron microscopy. Three major pollen types differing fundamentally in exine sculpturing were found. In the parasitic tribePedicularieae retipilate sculpturing is the most widespread type representing a plesiomorphic character state from which the two other types are derived. Of these, reticulate sculpturing is confined toOdontites, whereas a complex retirugulate pattern was found only in the monotypic Near East genusBornmuellerantha. Within the retipilate and the reticulate major types eight minor types were distinguished based on the differential correlation of exine surface morphology, size, shape and amb form. The pollen data are generally well correlated with macromorphological features and furnish important taxonomic characters at the genus—as well as at the specieslevel. 相似文献
118.
东北槭属的种子表皮雕纹及其在分类上的意义 总被引:1,自引:0,他引:1
借助于扫描电子显微镜,对我国东北地区槭属(Ace)的11种变种的种皮雕纹进行了扫描观察,并拍制了电镜照片。从种皮的雕纹类型看,槭树属的种皮可以概括为四种类型:(1)嵌合型;(2)穴状条纹型;(3)条纹型;(4)网格型;雕纹的形态也支持了色木槭和元宝械作为两个独立种的处理意见;以及小果紫花槭作为紫花槭(Acerpseudo-siebolidianum(Pax.)Kom)的种下等级变种(var.kor 相似文献
119.
半日花花粉形态种内变异及其花粉地理研究 总被引:19,自引:2,他引:17
用扫描电镜在个体水平上研究了产自两个地区的半日花花粉,并首次发现花粉种内变异与其地理分布之间的显著相关,半日花花粉形态在种内个体之间存在差异,以餐壁纹饰明显分为穿孔型和条纹型花粉;按形状和大小又可分为近球形较小和长球形较大花粉。外壁纹饰与形状、大小所得类型基本吻合。本种花粉,因所处地理环境的不同而外壁纹饰也有明显差异,条纹型花粉分布于新疆天山地区,而穿孔型花粉出现在内蒙古伊盟桌子山,并认为花粉外壁 相似文献
120.
The ATP-binding Cassette Transporter OsABCG15 is Required for Anther Development and Pollen Fertility in Rice 总被引:1,自引:0,他引:1
Plant male reproductive development is a complex biological process, but the underlying mechanism is not well understood. Here, we characterized a rice (Oryza sativa L.) male sterile mutant. Based on map‐based cloning and sequence analysis, we identified a 1,459‐bp deletion in an adenosine triphosphate (ATP)‐binding cassette (ABC) transporter gene, OsABCG15, causing abnormal anthers and male sterility. Therefore, we named this mutant osabcg15. Expression analysis showed that OsABCG15 is expressed specifically in developmental anthers from stage 8 (meiosis II stage) to stage 10 (late microspore stage). Two genes CYP704B2 and WDA1, involved in the biosynthesis of very‐long‐chain fatty acids for the establishment of the anther cuticle and pollen exine, were downregulated in osabcg15 mutant, suggesting that OsABCG15 may play a key function in the processes related to sporopollenin biosynthesis or sporopollenin transfer from tapetal cells to anther locules. Consistently, histological analysis showed that osabcg15 mutants developed obvious abnormality in postmeiotic tapetum degeneration, leading to rapid degredation of young microspores. The results suggest that OsABCG15 plays a critical role in exine formation and pollen development, similar to the homologous gene of AtABCG26 in Arabidopsis. This work is helpful to understand the regulatory network in rice anther development. 相似文献