山鸡椒雄花花芽发育形态解剖特征观察

采用体视显微镜、扫描电镜和石蜡切片技术对山鸡椒（Litsea cubeba（Lour.） Pers.）雄花花芽分化发育的外部形态和内部解剖结构进行了观察研究。结果显示:（1）山鸡椒雄花花芽分化发生可分为5个时期，即未分化期、花序原基分化期、苞片原基分化期、花原基分化期和花器官分化期，其中花器官分化期又可细分为花被原基分化期、雄蕊原基分化期和雌蕊原基分化期；各相邻分化时期存在一定重叠现象；花期从翌年1月上旬至3月下旬。（2）雄花成熟结构中具有独特的雄蕊蜜腺，蜜腺绿色且形态不规则，着生于内轮雄蕊基部，分布于花丝两侧，夹在内外轮雄蕊的花丝之间，与内轮花丝紧密相连。（3）雄蕊花药四室，花药壁发育属于基本型；腺质绒毡层；小孢子母细胞减数分裂过程中胞质分裂属于连续型；成熟花粉为2-细胞花粉粒；成熟花粉粒外壁刺突较多，刺突基部膨大，外壁露出部分粗糙，无薄壁区，有少数小穿孔。（4）山鸡椒雄花中绝大多数雌蕊发育至腹缝线卷合形成子房室时停止，柱头发育不良或者败育，花柱缩短或缺失，不能受精，直到开花结束，即发生退化。本研究明确了山鸡椒雄花花芽发育发生各个阶段时间、形态变化特点及外部形态变化特征，山鸡椒小孢子发生、雄配子体发育至散粉期变化特点和规律以及雄花中退化雌蕊发育的进程，可为山鸡椒优良品种选育、调控花期和提高结实率提供一定的参考。

Observation of the morphological and anatomical characteristics of male flower bud development in Litsea cubeba(Lour.) Pers.

To clarify the process of flower bud development in male flowers of Litsea cubeba(Lour.) Pers., we investigated the differentiation and development of the morphology and anatomy of male flower buds using stereomicroscopy, paraffin technology, and scanning electron microscopy. The results showed that: (1) The differentiation period of the male flower bud in L. cubeba was divided into five stages, including undifferentiation, inflorescence primordium differentiation, bract primordium differentiation, flower primordium differentiation, and floral organ differentiation, with the last stage further subdivided into perianth primordium differentiation, stamen primordium differentiation, and pistil primordium differentiation. There was some overlap in each differentiation stage. Flowering was from early January to late March the following year. (2) Mature L. cubeba males had unique irregular green stamen nectaries, which were borne at the base of the inner stamens, distributed on both sides of the filaments, intertwined with the filaments of the inner and outer stamens, and closely connected with the inner filaments. (3) Each anther had four pollen sacs and the development of the anther wall followed the basic model. The tapetum was glandular. Microspores were continuous during meiosis cytokinesis, and mature pollen grains were 2-pollen cells with very few microspore abortion during development. There were more spikes in ripe pollen exine, which was base dilated, and the exposed portion of the outer wall showed a rough, non-thin wall area, with a few small perforations. (4) Most pistils were arrested when the suture of abdominal cells formed into a peritoneal cavity. Therefore, the pistil had no stigma, and the style was shortened or missing,which process was called degradation. Fertilization did not happen until the end of flowering. The process was called degradation. We directly obtained the characteristics and patterns of male flower bud development, as well as the corresponding external morphogenesis, microsporogenesis, male gametophyte development, shedding, and development process of the pistillode in L. cubeba. These results provide a reference for the florescence regulation,selection and breeding of superior varieties of L. cubeba.