异叶苦竹大小孢子及雌雄配子体的发育(英文)

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Embryological characters of Arundinaria simonii f. heterophylla were reported in this article. The anthers were tetrasporangiate in which the cytokinesis of microsporocyte in meiosis was successive type and the produced microspore tetrads were bilaterally symmetrical. The cells of tapetum layer with dense cytoplasm were secretory type, and they began to degenerate during meiosis division. The mature pollen was trinucleate. The single ovule with parietal placenta was anatropous, double integument and tenuinucellatae. The development of the embryo sac was polygonum type. Generally the florets close to the base of spikelets bloomed earlier than others, and development of both stamens and pistils within a spikelet was synchronized. The anthers were tetrasporangiate in which the cytokinesis of microsporocyte in meiosis was successive type and the produced microspore tetrads were bilaterally symmetrical. The cells of tapetum layer with dense cytoplasm were secretory type, and the began with degenerate during meiosis division. The mature ovule was trinucleate. The single ovule with parietal placenta was anatropous, double integument and tenuinucellatae. The development of the embryo sac was polygonum type. Generally the florets close to the base of spikelets bloomed earlier than others, and development of both stamens and pistils within a spikelet was synchronized.
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