陕西杨凌地区郁金香花芽分化的形态观察

以郁金香的两个品种朱迪斯(Judith Leyster)和大笑(Big Smile)为材料,采用石蜡切片法观察其花芽形态分化过程。结果表明,郁金香花芽分化从6月中旬开始,到8月初形成三棱形的雌蕊结束。其过程可分为未分化期、外轮花瓣分化期、内轮花瓣分化期、雄蕊分化期、雌蕊分化期5个时期。花芽顶端由未分化期的扁平状逐渐膨大成为圆丘状,而后在内轮花瓣分化期的后期开始变平变宽,直到雄蕊分化期出现凹陷。花芽的外部形态变化上,分化后期芽的生长速度明显快于前期。相比其他地区,杨凌地区郁金香花芽分化的开始时间较早,用时较长。

Morphological Observation on Flower Bud Differentiation of Tulip Bulb in Yangling Regin of Shaanxi

Two different tulip cultivars,Tulipa gesneriana cv.Judith Leyster and Tulipa gesneriana cv.Big Smile,were adopted in the experiment.The course of flower bud differentiation was observed during flower bud differentiation.The results showed that the flower bud differentiation was initiated from mid June,and triangular swollen gynoecium was formed in early August.The process could be divided into five phases: undifferentiation stage,outer petal differentiation stage,inner petal differentiation stage,stamen differentiation stage,and pistil differentiation stage.The top of flower buds inflated gradually into a dome-shape from the initial flat-shape,then started to become flatter and wider in the later stage of perianth differentiation,and finally showed a depression when the stamen differentiation occurred.In terms of changes in the external growth of flower bud,it grew much faster in the late stage than in the early stage of differentiation.The results showed that the flower bud differentiation of Tulip in Yangling is not only started earlier but also lasted longer than that in other place.