广西植物Issue(5)：631-640,10.DOI:10.11931/guihaia.gxzw201401046
川东獐牙菜（龙胆科）的胚胎学研究
Embryology of Swertia davidii (Gentianaceae)
摘要
Abstract
The study includes the development of microsporangium,male gametophy,megasporogenesis,female game-tophyte and embryogeny of Swertia davidii.The main results were as follows:anthers were tetrasporangiate.The development of anther walls conforms to the basic type and comprises of epidermis,endothecium,three middle layers and tapetum at the mature stage.The tapetum cells had dual origins and belonged to the glandular type,for the an-ther locules had degenerating tapetum nuclei in the middle,which were from the early dividing and intruding of the ta-petum.Three middle layers were ephemeral,endothecium reduced and epidermis persists and developed to become fi-brous-thickening.The cytokinesis of the microspore mother cell in meiosis was the Simultaneous type.Most of the microspore tetrads were tetrahedral and there were still a few other types,such as isobilateral,dilateral and “T”-shaped.Pollen grains were 2-celled when shed.The ovary was bicarpellate,unilocular with some series of ovules loca-ted at the parietal placentation.The ovule was unitegmic,enuinucellar and ana-campylotropous.The female gameto-phyte originated from the single-archesporial cell.The one chalazal megaspore in linear tetrad became the functional megaspore.The development of female gametophyte was the polygonum type.Before fertilization,two polar nuclei fused into a secondary nucleus.Three antipodal cells had multiseriate nuclei and distinct haustorium,and persisted like a layer of“outer endosperm”j ust out of the endosperm nucleus layer.Fertilization was porogamous and of premi-totic syngamy type.The development of endosperm conformed to nuclear type and the embryogeny corresponded to the solanum type.The embryo was at the early heart-shaped stage when seeds released from the capsule.The divid-ing and persisting of the antipodal cells in some annual Gentianaceous plants were of significance in reproductive adap-tation and evolution.At the same time,comparative embryology among some species of Swertia was studied basing on some recent data.关键词
川东獐牙菜/胚胎学/獐牙菜属Key words
Swertia davidii/embryology/Swertia分类
农业科技引用本文复制引用
李鹂,黄衡宇..川东獐牙菜（龙胆科）的胚胎学研究[J].广西植物,2015,(5):631-640,10.基金项目
国家自然科学基金(31260102,31260077) （31260102,31260077）
湖南省高校创新平台开放项目(11k053) （11k053）
湖南省重点学科建设项目(JSU071301) （JSU071301）
