垂柳花蜜腺的发育解剖学研究

DEVELOPMENTAL ANATOMY OF FLORAL NECTARIES IN SALIX BABYLONICA

垂柳雌花蜜腺一枚，位于于房与花序轴之间，多呈扁平广卵形，由分泌表皮、泌蜜组织和维管束组成。雄花蜜腺呈基部相连的两枚突起，一枚位于花丝与花序轴之间，基部宽扁，上部棒状；另一枚位于花丝与苞片之间，棒状，仅由分泌表皮和泌蜜组织组成。雌、雄花蜜腺均起源于花托表面2—3层细胞。在蜜腺发育过程中，雌、雄花蜜腺泌蜜组织细胞的液泡发生规律性变化．雌花蜜腺为淀粉型蜜腺，而雄花蜜腺为非淀粉型蜜腺。雌、雄花蜜腺的原宜汁分别由蜜腺维管束韧应部或花丝维管束韧皮部提供，其蜜计最后均由分泌表皮细胞和变态气孔排出。

With the aid of light microscope,the morphology,structure and development of thefloral nectaries in Salix babylonica Linn. were investigated and the relationship betweenthe structure and the secretion of nectar was discussed. The female flower has onenectary occuring on receptacle between ovary and inflorescence axis. The nectary isgenerally flat broad oval--shaped and consists of epidermis, nectariferous tissue and vascularbundle. The male floral nectary is the two protuberances connected at the hasal part.One located on receptacle between filaments and inflorescence axis is stick-shaped in theupper part and flat in the hasal part while the other between filaments and bract isstickshaped. Both of them are composed of epidermis and nectariferous tissue. The female andmale floral nectaries are derived from 2-3 superficial layers of cells of the receptacle.During the development of nectaries,the vacuoles in the female and male floral nectarieschange regularly. The female floral nectary is starch storing nectary,however the malefloral nectary is non--starch storing nectary. The prenectar of the female and male floralnectaries might be supplied by its phloem and phloem of the filaments respectively. Thenectar is exuded from the female and male floral nectaries by epidermal cells andnectariferous tissue cells via modified stomata.