平欧杂种榛雌花芽分化过程研究

Study on the process of female flower bud differentiation in Ping'ou hybrid hazelnut

采用石蜡切片法对平欧杂种榛(Corylus heterophylla Fisch.×C.avellana L.)品种平欧124号的雌花芽分化过程进行了观察。结果表明,榛为单性花,其雌花芽的形态分化过程可划分为花芽分化初期、苞叶原基形成期(顶花序原始体出现期)、花蕾原基形成期、果苞原基形成期、雌蕊原基形成期(包括花柱原基形成期和子房显现期)和花柱伸长期6个阶段。在沈阳地区,平欧124号的顶花序原始体主要在7月中旬形成,之后逐渐分化出果苞、花柱和子房;最后随着花柱原基的不断伸长,雌花芽形态分化结束,全部过程历时2～3个月。观测中发现单个花蕾原基上可形成单一花柱或双生花柱。

The process of flower bud differentiation in Ping＇ou hybrid hazelnut （Corylus heterophylla Fisch.×C. avellana L.） cultivar Ping＇ou 124 was observed by means of paraffin-cut section. The results indicated that： the flower of the Ping＇ou hybrid hazelnut was unisexual; the morphological process of its female bud differentiation could be divided into six developmen- tal stages, i.e., the initial stage of flower bud differentiation, subtending-leaf-primordium emerging stage or terminal-inflo- rescence-primordium emerging stage, flower-bud-primordium emerging stage, bract-primordium emerging stage, pistil-primordium emerging stage （including the style-primordium emerging stage and ovary emerging stage） and style stretching stage. In Shenyang region, the terminal inflorescence primordium mainly emerged in the middle of July ; then bract, style and ovary were differentiated gradually ; with the elongation of style, the morphological differentiation of female flower bud ended; the whole process lasted 2 to 3 months. It was discovered that single or double styles were formed on one flower-budpremordium.