【作者】 林树燕；

【导师】 方炎明；

【作者基本信息】 南京林业大学 ， 植物学， 2009， 博士

【摘要】 本文以鹅毛竹(Shibataea chinensis)和异叶苦竹(Arundinaria simonii f. albostriatus)为材料,首次对其有性生殖的全过程进行了较为详细的研究,在此基础上,分析了鹅毛竹不结实和异叶苦竹结实率低的原因,研究结果如下:通过野外定位观测,对两个竹种的开花动态、繁育系统及花粉萌发率等进行了观察和检测。鹅毛竹为无限花序,假小穗簇生,花芽一般于10月初在当年生新竹各节上分化,至第二年3月份开花。开花时内、外稃不张开,未见种子;异叶苦竹为有限花序,通常在往年开花竹株上开花,当年3月形成花芽并开花。开花时内、外稃张开,果实为颖果。异叶苦竹繁育系统属于以异交为主,部分自交亲和,需要传粉者。两个竹种花粉萌发率差异显著,异叶苦竹花粉萌发率显著高于鹅毛竹。研究采用了电镜、荧光显微、石蜡制片等技术。在两个竹种的大、小孢子和雌、雄配子体发育过程的研究中,发现两者的花药壁发育为单子叶型,绒毡层为腺质型,减数分裂产生左右对称型小孢子,花粉粒为2或3细胞型。胚囊发育类型为蓼型。在异叶苦竹双受精、胚和胚乳的发育过程的研究中,发现其双受精发生在授粉后15-20h,合子休眠期较长,为5d,胚的发育类型为禾本型,胚乳发育类型为核型。鹅毛竹不结实的原因在于花粉败育和自然授粉不良。异叶苦竹结实率低的原因与零星开花的传粉有效性及花粉管生长过程中受到抑制有关。更多还原

【Abstract】 The sexual reproduction process of two bamboos, Shibataea chinensis which was abortive and Arundinaria simonii f. albostriatus which had low seed-setting rate, was investigated for the first time and the reason why Shibataea chinensis was abortive and Arundinaria simonii f. albostriatus had low seed-setting rate was analyzed. The results are as follows:The flowering phenology of Shibataea chinensis was different from that of Arundinaria simonii f. albostriatus. The flower buds differentiated in October of last year and bloomed in March of next year for Shibataea chinensis. The whole process lasted for about 6 months.While the flower buds differentiated in March and bloomed in April for Arundinaria simonii f. albostriatus. The inflorescence structure of Shibataea chinensis is indeterminate type, but it is determinate one for Arundinaria simonii f. albostriatus. The breeding system of Arundinaria simonii f. albostriatus is mainly outcrossing, but partly may be self-compatible. Artificial pollination can improve the seed setting. The seeds could be harvested more or less every year. However, Shibataea chinensis never bore any seeds. The pollen germination rate of Arundinaria simonii f. albostriatus was obviously higher than the one of Shibataea chinensis.Using TEM, SEM, fluorescence staining and traditional paraffin section, the process of megasporogenesis and microsporogenesis and the development of female and male gametophyte of the two bamboo species were studied. The anther wall consisted of four layers.They were epidermis, endothecium, middle layer and tapetum. The development of anther wall belonged to the monocotyledonous type. The tapetum was of typical glandular type. The cytokinensis was successive and the microspore tetrads are bilaterally. Mature pollen grains were 2-cell or 3-cell with one germinal aperture. The simple ovary consisted of two carpels. Single ovule with parietal placenta was anatropous, double integument and tenuinucellatae. The megasporocyte underwent meiotic division to form four megaspores arranged in a line, and the micropylar megaspore was the functional one. The formation of the embryo was of polygonum type. The fertilization of Arundinaria simonii f. albostriatus occurred in15-20h after pollination. The zygote had a dormant for 5 days. The development type of embryo is graminad and the development type of endosperm is nuclear.The reasons why Shibataea chinensis is abortive lies in the low pollen germination rate , abortive pollen and poor pollination. While the low seed-setting rate of Arundinaria simonii f. albostriatus is due to the poor pollination effectiveness and inhibited pollen tube growth .更多还原