Amitrano Chiara, De Francesco Sara, Durante Marco, Tinganelli Walter, Arena Carmen, De Micco Veronica
Department of Agricultural Sciences, University of Naples Federico II, 80055 Naples, Italy.
Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmsatdt, Germany.
Plants (Basel). 2024 Dec 19;13(24):3541. doi: 10.3390/plants13243541.
Numerous challenges are posed by the extra-terrestrial environment for space farming and various technological growth systems are being developed to allow for microgreens' cultivation in space. Microgreens, with their unique nutrient profiles, may well integrate the diet of crew members, being a natural substitute for chemical food supplements. However, the space radiation environment may alter plant properties, and there is still a knowledge gap concerning the effects of various types of radiation on plants and specifically on the application of efficient and rapid methods for selecting new species for space farming, based on their radio-resistance. Thus, the hypotheses behind this study were to explore the following: (i) the pattern (if any) of radio-sensitivity/resistance; and (ii) if the morphological parameters in relation with pigment content may be a feasible way to perform a screening of radiation responses among species. To perform this, we irradiated dry seeds of basil, rocket, radish, and cress with iron (Fe; 1550 MeV/(g/cm²)) and carbon (C; 290 MeV/u, 13 keV/µm) heavy ions at the doses of 0.3, 1, 10, 20, and 25 Gy to investigate the growth responses of microgreens to acute radiation exposure in terms of morphological traits and photosynthetic pigment content. Results indicate that the microgreens' reaction to ionizing radiation is highly species-specific and that radiation is often sensed by microgreens as a mild stress, stimulating the same morphological and biochemical acclimation pathways usually activated by other mild environmental stresses, alongside the occurrence of eustress phenomena. Over extended periods, this stimulus could foster adaptive changes, enabling plants to thrive in space.
外星环境给太空种植带来了诸多挑战，目前正在开发各种技术生长系统，以实现太空种植微型蔬菜。微型蔬菜具有独特的营养成分，很可能会融入宇航员的饮食中，成为化学食品补充剂的天然替代品。然而，太空辐射环境可能会改变植物特性，对于各类辐射对植物的影响，尤其是基于抗辐射性为太空种植选择新物种的高效快速方法的应用，仍存在知识空白。因此，本研究背后的假设是探索以下内容：（i）辐射敏感性/抗性的模式（若存在）；（ii）与色素含量相关的形态参数是否可能是筛选不同物种辐射反应的可行方法。为此，我们用铁（Fe；1550 MeV/(g/cm²)）和碳（C；290 MeV/u，13 keV/µm）重离子，以0.3、1、10、20和25 Gy的剂量辐照罗勒、芝麻菜、萝卜和水芹的干种子，从形态特征和光合色素含量方面研究微型蔬菜对急性辐射暴露的生长反应。结果表明，微型蔬菜对电离辐射的反应具有高度物种特异性，而且辐射通常被微型蔬菜视为一种轻度胁迫，会刺激通常由其他轻度环境胁迫激活的相同形态和生化适应途径，同时还会出现适度应激现象。在较长时期内，这种刺激可能会促进适应性变化，使植物能够在太空中茁壮成长。
