Plant biology experiments in real and simulated microgravity have significantly contributed to our understanding of physiology and behavior of plants. How do plants perceive microgravity? How that perception translates into stimulus? And in turn plant's response and adaptation to microgravity through physiological, cellular, and molecular changes have been reasonably well documented in the literature. Knowledge gained through these plant biology experiments in microgravity helped to successfully cultivate crops in space. For instance, salad crop such as red romaine lettuce grown on the International Space Station (ISS) is allowed to incorporate into the crew's supplementary diet. However, the use of plants as a sustainable bio-regenerative life support system (BLSS) to produce fresh food and O2, reduce CO2 level, recycle metabolic waste, and efficient water management for long-duration space exploration missions requires critical gap filling research. Hence, it is inevitable to reflect and review plant biology microgravity research findings time and again with a new set of data available in the literature. With that in focus, the current article discusses phenotypic, physiological, biochemical, cell cycle, cell wall changes and molecular responses of plants to microgravity both in real and simulated conditions with the latest literature.

真实和模拟微重力下的植物生物学实验极大地促进了我们对植物生理学和行为的理解。植物如何感知微重力？这种感知如何转化为刺激？反过来，植物通过生理、细胞和分子变化对微重力的反应和适应已经在文献中得到了很好的记录。通过这些微重力植物生物学实验获得的知识有助于在太空中成功种植作物。例如，允许将国际空间站 (ISS) 上种植的红色长叶莴苣等沙拉作物纳入机组人员的补充饮食中。然而，使用植物作为可持续的生物再生生命支持系统 (BLSS) 来生产新鲜食物和氧气、降低二氧化碳水平、回收代谢废物、长期太空探索任务的高效水资源管理需要关键的空白填补研究。因此，不可避免地需要通过文献中可用的一组新数据一次又一次地反映和审查植物生物学微重力研究结果。本文重点讨论了植物在真实和模拟条件下对微重力的表型、生理、生化、细胞周期、细胞壁变化和分子反应，并结合最新文献。