Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value

	Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value
	Xue Chunying ; He Tingnong ; Li Dezhu
刊名	云南植物研究 ; Xue Chunying,He Tingnong,Li Dezhu.Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value.云南植物研究,2002,24(1):75-81
	2002
英文摘要	This paper reports the mega-, micro-sporogenesis and female-, male-gametogenesis of Swertia cincta for the first time, with the aim of discussing the systematic position of section Platynema and section Ophelia of Swertia. Anthers are tetrasporangiate. The development of anther walls conforms to the dicotyledonous type. The tapetum cells have dual origin and are similar to the glandular type. There are two middle layers. The endothecium and epidermis persist. Cytokinesis in the microsporrocyte meiosis is simultaneous type and the microscpore teads are tetrahedral. Pollen grains are 3-celled. The ovary is bicarpellum and unilocular. The placentation is of suparietal placentation with 12 series of ovules. The ovules. The ovule is unitegmic, tenuinucellar and ana-campylotropous, The embryo sac orignates from the single-archesporial cell. The one chalazal megaspore in lienar tetrad become the functional megasore. The development of embryo sac is of the polygonum type. Before fertilization, two polar nuclei fuse into one secondary nucleus. Three antipodal cells persisted and divided into 5-8 cells. A comparison between two sections indicates that section Plathnema is better treated as distinct section and is more advanced than section Ophelia according to the evolutionary trends of embryological characters.
内容类型	期刊论文
源URL	[http://ir.nwipb.ac.cn/handle/363003/812]
专题	西北高原生物研究所_中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Xue Chunying,He Tingnong,Li Dezhu. Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value[J]. 云南植物研究, Xue Chunying,He Tingnong,Li Dezhu.Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value.云南植物研究,2002,24(1):75-81,2002.
APA	Xue Chunying,He Tingnong,&Li Dezhu.(2002).Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value.云南植物研究.
MLA	Xue Chunying,et al."Embryology of Swertia cincta (Gentianaceae) and Its Systematic Value".云南植物研究 (2002).