Objective]The aim of the study was to explore the adaptation of Haloxylon ammodendron flower to arid environment in the Gurbantunggut desert of China.[Method]The anatomical structures of H. ammodendron flower were observed using paraffin section and scanning electron microscope and its pollen-ovule ratio was also measured.[Results]H. ammodendron flower attached at the new shoots (assimilating branches). The flower was bisexual and small,with a diameter of about 1.0 mm. The flower located at axil solitarily,only with calyx. The base of ovary positioned was within flower disk and the flower had no corolla. The flower had five tepals. The tepal was free,green,papery or scarious. The inner surface of the base was often arachnoid. The flower had five stamens and the stamens were yellow,which belonged to synantherous stamen. The solid style was short with many secretory cells and had no style in the center. The flower had two scaphoid bractlets,outside the cuticula. The bractlet had scarious margins. The ovary had vascular bundle and the connectivum of anther had vascular and the vascular preserves until anther dehiscence. When the flower was mature,the stigma was close to the base of anther. The anther height was slightly higher than that of the fingered stigma,providing a suitable spatial position to self-pollination. The flower had tiny and light but rich pollen grains. The P/O value was 64 815,which was suitable to anemophilous pollination. Based on the observations using scanning electron microscope,we found the pollen grain was nearly spherical with warty ornamentation. The length of polar axis and equatorial axis was 19.08~21.02 μm,18.59~19.18μm,respectively.[Conclusion]Our results indicated that H. ammodendron have two pollination ways(self-pollination and cross-pollination). The external feature and anatomical structure showed H. ammodendron flower has strong capacity to adapt to desert environment.%【目的】以古尔班通古特沙漠植被优势种梭梭为对象，探讨梭梭花解剖特征对沙漠干旱环境的适应。【方法】运用石蜡切片和电镜扫描等方法对梭梭的花部解剖结构和花粉粒形态进行了观察，对花粉-胚珠比（P/O）做了检测。【结果】梭梭花着生在当年生新梢（同化枝）上，花冠小，直径约1 mm，单生叶腋，仅具花萼，为两性花。子房基部陷于花盘内，无花冠。花被片5，离生，绿色，纸质或干膜质，内面基部常具蛛丝状毛。雄蕊5枚，黄色，属聚药雄蕊。梭梭的花柱短，柱头指状，实心花柱，中央无花柱道，有许多分泌细胞。小苞片2，舟状，外被角质层，边缘膜质。梭梭子房中分布有维管束，在花药的药隔处有维管束且开裂后维管束仍留存。当梭梭花成熟时柱头紧靠着花药基部，雄蕊略高于雌蕊，为自花授粉提供了极好的空间位置。花粉粒直径小，质量轻，数量多，P/O值为64815，适于风媒传粉。进一步的扫描电镜观察表明，梭梭近似球形的花粉粒表面具瘤状纹饰，花粉粒极轴长度为19.08~21.02μm，赤道轴长度为18.59~19.18μm。【结论】梭梭存在自花和异花两种传粉途径；梭梭花外观形态和解剖结构特征表明了梭梭对沙漠干旱环境的高度适应。
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