舞钢玉兰芽种类与成枝成花规律的研究

报道了舞钢玉兰芽的种类、分枝习性与成枝生长规律，拟花蕾、着生位置、解剖结构及其分化发育成花规律。从中发现：（1）当年生枝上有休眠芽、叶芽（侧叶芽和顶叶芽）、拟花蕾3种；（2）拟花蕾有缩台枝、芽鳞状托叶、雏枝、雏芽及雏蕾组成，因其外形似“花蕾“，称为“拟花蕾“；（3）缩台枝是枝与花着生的中间过滤枝变阶段，是由母枝顶端节间缩短、增粗的枝段和当年由雏枝生长的1次极短新枝所组成；（4）4-5月及7-8月前后两批形成的拟花蕾，均经过未分化发育期、花被分化发育期、雄蕊群分化发育期及离心皮雌蕊群分化发育期，各期均依次递后交错进行，但不逆转，也不能截然分开，直到翌春花分化发育全部结束，开花后才能结实；（5）芽鳞状托叶是托叶的变态，最外层薄革质，外面密被短柔毛，始落期6月中下旬，其余纸质--膜质，外面密被或疏被毛柔毛，翌春开花时脱落完毕；（6）雏蕾有雏梗、雏花及包被雏花的佛焰苞状托叶组成；（7）分枝习性与成枝生长规律与预生分枝及预生一同生分枝呈单阶无歧、单阶1歧生长规律，稀有单阶2歧生长规律。

Study on Bud Types and Rules of Flower Bud Differentiation and Branches' Forming in Yulania wugangensis

Some results of Yulania wugangensis are firstly studied in this paper, which are types, ramification characteristics, rules of growing into branches of buds and locus, anatomy, rules of differentiating into flowers of similar flower buds. The results as followings: (1) There are three types of buds on the spring branches of present year; latent buds, leaf buds (lateral leaf buds and apical leaf buds) and similar flower buds. (2) Similar flower bud is composed of Suotai-branchlet, stipule like bud scales, beginning branchlet, beginning leaf buds and beginning flower bud. It is called similar flower bud because it's shape likes flower bud; (3) Suotai-branchlet is transition phase between branchlet and flower setting location. It consists of the shortened, stout piece of the apex of maternal branch and first short new branchlet which developing from beginning branchlet; (4) The similar flower buds twice formed during AprilMay and JulyAugust, both experienced four stages, which are indifferentiation period, differentiation period of perianth, androecium cluster and apocarpous pistil cluster. These stages progress alternately in turn, but don't reverse and separate completely. The buds could not bloom and bear until flower buds differentiation to be over in next spring; (5) Stipule like bud scales is the anomalism of stipule, it's most outside layer is thin, coriaceous and densely covered by short fluff, which begin to fall off during the middle or last ten-days of June, and the others are paper or membranous texture and densely or sparsely covered by long fluff, which do not finish falling off till blooming in the second spring; (6) Beginning flower bud is composed of beginning peduncle, beginning flower and spathiformis stipule enveloping beginning flower; (7) Ramification characteristics and rules of growing into branches of buds belong to prolepsis and prolepsis-synlepsis, behaving the regularity of single step without branch, single step having one branch, rarely two branches. In conclusion, these results are significant to resolve the problem of numerous and jumbled about classifying and describing of Magnolia, and build a new classifying system to subfamily of Magnolioideae.