青花菜花球花芽分化与发育的解剖研究

STUDIES ON ANATOMY OF THE FLOWER BUD DIFFERENTIATION AND DEVELOPMENT OF THE CURD OF BROCCOLI

本文对青花菜(Brassica oleracea var.italica)的花球花芽分化与发育进行解剖学研究.在解剖显微镜下解剖研究的基础上,应用扫描电子显微镜观察摄影,将青花菜的花序分化发育形成花球的过程分为7期.其分化发育规律是:侧花茎原基的分化级数由外而内地逐渐减少,最外最先分化的侧花茎原基先发育,第2～3级分化后,便分化花原基、分化至第4级的为数不多,个别分化至第5级.往内仅有第2级甚或第1级侧花茎原基的分化,便分化花原基.最后主花茎端直接分化花原基,陆续发育成花雷体.整列复总状花序最后形成的花球,是由短缩、肉质的主花茎与一定数量的分球组成产品器官.每分球则由短缩、肉质的第1级侧花茎及其上各级侧花茎和花雷群发育而成.决定花球大小和重量的主要形态解剖指标是——分球数目和分球中侧花茎的分化级数及其上具多级侧花茎的数目及其发育程度.尤其是较大分球的数目,更是指标中的重要标志,只有在这些分球及其侧花茎获得充分发育的基础上,才能发挥其潜在势能的良好效应.为青花菜的高产、优质奠定基础.本研究为青花菜栽培及选育种制定相应的技术措施,提供解剖学的依据.

The anatomy of the floral bud differentiation and the curd development of broccoli (Bras-sica oleracea var. italica)was studied with dissected microscope and scanning electric microscope. The outermost lateral scape primordia developed first and then the inner primordia. Following the development of the first order lateral scape primordia,the second and third order lateral scape primordia differentiated. Then ,the floral primordia initiated. Though the development of the fourth order lateral scape primordia was very few, the fifth order lateral scape primordia would still differentiate in a few cases. As to the inner part, the lateral scape primordia could only differentiate the first or the second order. Later on,the apex of main scape differentiated into flower primordia and developed into floral bud. The curd of broccoli was an organ product that was consisted of a complex racemose inflorescence with shortened and fleshy main scape and many branch curds. Every branch curd was developed from shortened and fleshy lateral scape of first order or/and other order lateral scapes with the floral buds located on them. The size and weight of the broccoli curd was determined by the number of branch curd and the differentiated orders of lateral scape. The larger number of the branch curds and the lateral scapes was the important morphological index. As the branch curds and their lateral scapes were well developed, the potential production will be obtained. The aim of thes paper is to show with the anatomical point of view that the development of broccoli curd and the differentiation of the lateral scape of branch curds can be regulated in order to get the high quality and quantity of broccoli curd.