条纹龙胆的胚胎学研究

首次报道了条纹龙胆（Ｇｅｎｔｉａｎａ ｔｓｒｉａｔａ Ｍａｘｉｍ．）的胚胎学特征，研究结果用以讨论龙胆属狭蕊组（Ｇｅｎｔｉａｎａ Ｓｅｃｔ．Ｓｔｅｎｏｇｙｎｅ）的系统演化关系。主要研究结果如下：花药四室；药壁发育为双子叶型；绒毡层细胞仅来源于初生壁细胞，故绒毡层起源属单型起源，细胞单核，原位退化，属腺质型绒毡层，药隔处的绒毡层细胞经多次平周分裂形成２层至多层的绒毡层细胞，其余部位的绒毡层细胞仍为１

Embryologyof Gentiana striata (Gentianaceae)

This paper describes embryological characters of Gentiana striata Maxim.For the first time,The results are used to discuss the systematic position of Gentiana Sect.Stenogyne.Anthers are tetrasporangiate.The development of anther walls conforms to the dicotyledonous type.The tapetum cells origin from the primary parietal cells,and thus the tapetum is of single origin.The development of the tapetum with uninucleate cells is of the Glandular type.The tapetal cells on the connective side show radial elongation or periclinal division and intrude into the anther locule.There are one middle layers.Parts of the epidermis and endothecium persist and the cells become pillar and fibrous.Cytokinesis in the microsporocyte meiosis is simultaneous type and the microspore tetrads are tetrahedral.Pollen grains are 3-celled.The ovary is bicarpellary and unilocular.The placentation is of reduced parietal placentae with 4 rows of ovules.The type of ovule is Hypertropous.The ovule is unitegmic and tenuinucellar.The embryo sac originates from a single-archesporial cell.The one chalazal megaspore in linear tetrad becomes functional.The development of embryo sac is of the Polygonum type.Before fertilization,two polar nuclei fuse into a secondary nucleus.Three antipodal cells persist.Flowers are protandrous.Fertilization is porogamous.The development of the endosperm is of the Nuclear type.The embryogeny corresponds to the Soland type Physalis Ⅱ variation type.The present paper indicates that Gentiana Sect.Stenogyne is more similar to Tripterospermum than to other sections of Gentiana in embryological characters.Sect.Stenogyne might be separated from Gentiana.