花椰菜花球发育的解剖学观察

采用连续石蜡切片和电镜扫描技术对早、中、晚熟3个花椰菜品种的植株茎端分化过程进行观察.结果表明,其茎端发育可分为5个时期,即叶原基分化期,花球原基分化始期,花球原基形成期,花球形成、膨大和成熟期,抽苔和花器官分化期.花椰菜的食用花球是由许多肉质花梗和花器官原基组成的.花器官分化过程分为5个时期,即花原基分化期、萼片形成期、雄蕊和雌蕊形成期、花辦形成期、花药和胚珠形成期.花球发育过程发生的异常形态特征有小花原基、青花原基、腋花球原基和毛花原基.“小花”与“腋花球”可能是不适环境造成的;“青花”和“毛花”可能是品种本身存在的变异与环境互作所致.

Anatomical Observations on the Curd Development of Cauliflower,Brassica oleracea var.botrytis L.

Three cultivars,“80-day”,“80-day”and“100-day”,of cauliflower wcre used to study the differentiation and development of the shoot apex by means of paraffin section and electronic microscope scanning.The result indicated that the differentiation and devel- opment of the shoot apex of cauliflower could be divided into five stages,namely: the differentiation stage of leaf primordia,the initial stage of curd primordia,the formative stage of curd primordia,the stage of curd formation,expansion and mature,and the stage of bolt- ing and differentiation of flower organs.The edible curd of cauliflower is composed of lots of pedicels and the primordia of flower organs.Five stages could be recognized in the differentiation procedure of flower organs in the cauliflower plants,they were the differentiation of flower primordia,sepal formation,stamen and pistil formation,petal for- mation,and anther and ovule formation.Additionally,there were abnormal morphogenesis, i.e.the primordia of“buttoned”,“greened”,“hairlike”and“axillaryn”curd in the curd devel- opment procedure.“Bottoned”and“axillary”curds may be caused by unsuitable cultivation conditions,and“greened”and“hairlike”curds may be the result of species degeneration.