早实核桃雌花芽分化外部形态与内部结构关系的研究

以雄先型早实核桃辽宁1号为试材,通过观察照相和制作石蜡切片对雌花芽分化过程的外部形态及内部结构进行了研究。结果表明:雌花芽外部形态变化主要表现在大小、形状和鳞片的质地、颜色等方面,雌花芽内部结构主要分为5个时期,雌花芽外部形态和内部结构存在密切的关系;在成花诱导期,雌花芽较小,呈扁三角形,外被3 - 5层鳞片,质软、鲜绿色;在花柄分化期,雌花芽逐渐增大,为阔三角形或扁圆形,鳞片5 - 7层,变硬,幼叶形成;在苞片分化期,雌花芽大小和形状没有明显变化,鳞片层数增加,逐渐木质化,颜色变成黄绿色直至褐色;在花被分化期,雌花芽由褐色变成灰绿色,鳞片逐渐张开;在雌蕊分化期,雌花芽再次增大,鳞片逐渐脱落,幼叶展开。雌花芽外部形态指标可以直观地反映出内部结构的变化。这一指标可以作为判断花芽分化时期的方便、快捷、直观手段。

Relationship between External Morphology and Anatomical Structure of Precocious Walnut during Pistillate Flower-bud Differentiation

External morphology and internal anatomical structure of pistillate flower-bud of protandrous precocious walnut cultivar of 'Liaoning 1'(Juglans regia L.) were observed during bud differentiation. External morphology presented various in size, shape and squama texture and color and so on. Internal anatomical structure could be marked into five periods. A close relationship between external morphology and anatomical structure of pistillate flower-bud was found. The pistillate flower-bud were small, flat triangle, with 3-5 soft, bright green squama in flower-bud induction period ;in the pedicel differentiation stage, the pistillate flower-bud was gradually increased to broad triangle or oblate shape, the squamas added to 5-7 layers and became hard and the young leaves formed; in the period of bract differentiation, the size and shape of pistillate flower did not change obviously, its squamas had more layers and became lignifications gradually and its color varied from yellow-green to brown; in the period of perianth differentiation, the color of pistillate flower-bud changed from brown to ash-green and its squamas spread gradually; in the period of pistil differentiation, the pistillate flower bud size increased again, its squamas spread further and young leaves extended. The external morphology of pistillate flower-bud could indirectly reflect the changes of internal structure and could serve as a convenient, fast and intuitionistic indicator for flower-bud differentiation.