Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy.
Department Oral and Maxillofacial Surgery/Pathology, Amsterdam Movement Sciences and Amsterdam Bone Center (ABC), Amsterdam University Medical Center Location VUmc and Academic Center for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands.
Sci Rep. 2024 Nov 14;14(1):27979. doi: 10.1038/s41598-024-79109-4.
Space agriculture, pivotal for sustainable extraterrestrial missions, requires plants that can adapt to altered gravitational conditions. This study delves into the adaptive responses to altered gravity of Wolffia globosa, an aquatic plant known for its rapid growth and high nutritional value. The research aimed to analyse the effect of simulated microgravity and hypergravity on relative growth rate (RGR), morphological characteristics, protein content, and the correlation between plant size and growth rate of Wolffia globosa. The study highlighted the responses of the species to altered gravity, uncovering inherent variability among seven different clones of W. globosa. Results show a base variability among clones in terms of RGR, size and protein content. Furthermore, some clones are affected by simulated microgravity, showing a decrease in RGR. Differently, under hypergravity, clones showed RGR higher than in 1 g control, therefore revealing a novel plant response to hypergravity. Morphological adaptations to gravity alterations were also evident. Among the studied clones, significant morphological changes were observed, further underlining the peculiar adaptation to the hypergravity environment. Differently, under simulated microgravity, morphology was generally stable across clones. A key finding of the study was the significant negative correlation between RGR and the physical dimensions of the plants: the fastest growth was associated with the smallest dimensions of the plants. This correlation might have practical implications in selecting clones for space cultivation, that leads to compact yet highly productive clones. The analysis of the protein content of all the clones revealed mostly no significant changes under hypergravity. Otherwise, a general decrease in protein content was observed under simulated microgravity. Overall, the study confirms the suitability of W. globosa for space agriculture and provides new insights into the perspective of using W. globosa as an alternative crop species for protein production for manned Space missions. Furthermore, it underscores the need for focusing on the clones and the selection of the W. globosa plants that are best adapted to the environmental conditions of space; therefore, selecting those with the best combination of biomass production (by means of growth rate, size), and protein content.
太空农业对于可持续的外星任务至关重要，需要能够适应改变的重力条件的植物。本研究深入探讨了水生植物浮萍（Wolffia globosa）在改变的重力下的适应性反应，浮萍以其快速生长和高营养价值而闻名。该研究旨在分析模拟微重力和超重对相对生长率（RGR）、形态特征、蛋白质含量以及浮萍大小和生长率之间相关性的影响。该研究强调了该物种对改变的重力的反应，揭示了七个不同浮萍克隆之间固有的可变性。结果表明，克隆之间在 RGR、大小和蛋白质含量方面存在基础可变性。此外，一些克隆受到模拟微重力的影响，RGR 降低。相反，在超重下，克隆的 RGR 高于 1g 对照，因此揭示了植物对超重的新反应。对重力变化的形态适应也很明显。在所研究的克隆中，观察到了显著的形态变化，这进一步强调了对超重环境的特殊适应。相反，在模拟微重力下，形态在克隆之间通常是稳定的。该研究的一个关键发现是 RGR 与植物物理尺寸之间存在显著的负相关：生长最快与植物尺寸最小相关。这种相关性在选择用于太空种植的克隆时可能具有实际意义，可导致选择紧凑但高度多产的克隆。对所有克隆的蛋白质含量的分析表明，在超重下大多没有显著变化。相反，在模拟微重力下观察到蛋白质含量普遍下降。总的来说，该研究证实了浮萍适合太空农业，并为使用浮萍作为载人航天任务蛋白质生产的替代作物提供了新的见解。此外，它强调了需要关注克隆以及选择最适应太空环境条件的浮萍植物的重要性；因此，选择那些具有最佳生物量生产（通过生长率、大小）和蛋白质含量组合的植物。
