中文摘要：

向重力性反应是植物适应地球重力环境的一个重要生理过程,是植物正常生长发育不可缺少的反应机制,但是,微重力是否影响植物种子发育至今尚无一致性结论.本文研究了三维回转器回旋模拟微重力对拟南芥种子发育（胚胎发育与代谢活动）的影响.研究结果表明,三维回转条件下,拟南芥果荚出现不规则弯曲或扭曲形态,形成的种子中可溶性糖和淀粉含量明显增加,盐溶性贮藏蛋白质含量显著降低而碱溶性蛋白质含量显著升高,球形胚时期的种子对三维回转处理最为敏感.对球形胚时期的植株进行短期的三维回转处理可抑制胚柄细胞的分裂和伸长,而胚柄伸长受阻可能会影响到营养物质向胚胎中输送,进而导致部分胚胎败育.对种子干燥脱水阶段的植株进行三维回转处理不影响胚胎的发育,但会导致种子贮藏蛋白质含量下降.

英文摘要：

Gravitropism is an important physiological response and an essential mechanism for plants to maintain the normal growth and development on earth. In the life cycle of higher plants, seed development is a key process, but whether gravity can affect the development of seeds has not been confirmed. In this study, the development of siliques and seeds of Arabidopsis under the 3D clinostat rotated condition was analyzed to examine whether seed development including formation of embryos and the activities of metabolism is affected by the altered gravity condition. Our results showed that in the 3D clinostat rotated treated Arabidopsis plants, the morphology of siliques showed an irregular curvature, and the cell division and elongation of suspensor were inhibited. The content of soluble carbohydrates and starch in the young and mature seeds obviously increased, while the content of salt soluble protein decreased. In addition, developing seeds at globular stage are most sensitive to the 3D clinostat rotated treatment with the inhibition of cell division and elongation of the suspensors. Suspensors are important for the transportation of nutrients into embryos and abnormal development of suspensor under the clinostat rotation condition might cause seed abortion.