Today, the Republic of China, which takes an active role in space studies, continues its space biology research within the scope of many human-crewed and uncrewed space missions managed by the Chinese National Space Administration.
Recently, the China Manned Space Program shared a detailed list of plant seed and microbial species selected for use in space biology research and sent into space on the Shenzhou XIV and Shenzhou XV rockets.
Shenzhou XIV and Shenzhou XV rockets were launched on June 5, 2022, and November 20, 2022, respectively, to dock at Tiangong, China’s Large Modular Space Station.
The shared list includes around 130 species from different contributors, such as various research institutes and universities. Studies to be carried out on the organisms listed here can be shown among the space biology research objectives of the China Space Program. The astronauts’ task is to study the vital parameters and developments of the selected organisms on the Tiangong Space Station.
Before examining the details of the previous works and future plans, let’s answer a particular question briefly; “What is the reason for plant and microorganism-focused research in space missions?”
Plant space biology research is of great importance for the future of space studies and humanity’s extraterrestrial colonization goals. As a source of oxygen and nutrients, plants will play a key role in establishing sustainable artificial ecosystems in long-term space missions. In addition to direct plant biology-oriented studies, it is necessary to deal with plant-related microorganisms in this direction.
The Focus of Space Biology Studies
The purpose of the experiments designed by the China Manned Space Program is to investigate the effects of cosmic radiation and microgravity on seeds of different types of plants and various types of microorganisms.
As seen in this study, microorganisms are examined in space biology by being evaluated in a much broader spectrum beyond their relationship with plants. For example, the role played by microorganisms in food processing by fermentation makes them highly valuable for long-term space missions.
As a result of the studies carried out, we can gain an insight into how space mission conditions can affect plants and microorganisms at the genome level.
The list of plant species published by the Chinese Manned Space Agency includes plants of high nutritional value and medical value. Besides such directly beneficial species, they also focused on parasitic plant species and salt-alkali-resistant plant species to understand their adaptive abilities. Within the scope of the research, extensive microbiology studies are carried out to understand plant-microorganism interactions and the behavior of microorganisms directly.
China’s current space biology research goals focus on adapting plants to the conditions of space missions and understanding the behavior of microorganisms in a broad spectrum.
Plant Space Biology Studies
China Space Program’s plant space biology studies focus on increasing crop efficiency in long-duration space missions. Today, we know that the plant species existing on Earth can partially adapt to the conditions of space missions and that using plants directly in space farms of the future in this way is costly and risky.
Research by Chinese scientist Yongming Liu and colleagues has shown that we must rely on plant biotechnology to improve plant health and adaptation for use during space missions. The research group has developed a new strategy called “Whole-Body Edible and Elite Plant (WBEEP)” to create highly nutritious products for space farming.
The WBEEP project aims to create entirely edible potato plants by inhibiting toxic components such as solanine in the plant’s body. As part of the study, they also reconfigure the associated biochemical pathways to provide a richer nutrient content from the potatoes to be grown.
The study, which focused on increasing production efficiency, uses RNA demethylation processes to alter photosynthetic efficiency and tuber formation. This project also includes optimizing root formation for better mineral uptake.
China is also using plant space biology research to increase plant productivity on Earth to meet the food needs of its growing human population. You can see the vast fields of Luyuan 502 wheat, which are widely planted in the northeastern regions of China. What’s interesting about these wheat fields is that the wheat seeds were exposed to space mission conditions in 340 km orbit of the Earth before they germinated on Earth.
It is known that seeds exposed to microgravity and radiation during space missions show adaptations to drought and some diseases after selection processes after mutagenesis.
Space Microbiology Studies
China’s space microbiology research has focused on using microorganisms in space pharmacy and biomedical studies. Microorganisms can be used in the biomedical and pharmaceutical fields to procure medical supplies, such as active drug components, for long-term space missions and future space colonies.
Besides their biomedical value, microorganisms are a part of plant-microbial interactions research carried out to increase plant productivity. While some studies directly use the soil microbiome, also called the rhizosphere, many studies focus on specific species to improve food fermentation techniques and probiotic production.
According to Liu (2017), space microbiology studies can be conducted through three fundamental theories for designing and developing future research. These theories relate to the high mutation capacity of microorganisms, the causes of mutations, and the conditions these mutations can cause.
According to the first theory, mutations could negatively affect the health of astronauts by causing pathogenicity and virulence. On the other hand, these mutations can result in a mutually beneficial relationship between microbes and humans. In short, mutations can describe the interaction of microbes with humans.
The second theory is related to mutations that can cause the production of biomedical substances such as metabolic products. It also shows that such mutations can generate antibiotic-resistant strains that could be dangerous to the health of astronauts.
Finally, the third theory focuses on the effects of space corrosion on microorganisms and the microbial contamination situation that may be associated. In this scenario, microbial interactions become a problem directly related to the biosecurity of spacecraft. However, these modifications and mutations could pave the way for creating new biomaterials.
As a result, while the starting point of the theories varies depending on the type of mutation, they contain separate scenarios that can lead to positive and negative consequences.
To reach Mars and beyond, we need to explore better ways to create sustainable artificial ecosystems based on plant and microbial research outputs. Current research focuses and trends show us that the importance of space biology and space botany will increase. These studies aim to provide food, oxygen, medicine, and biomaterials for long-duration space missions and colonization scenarios.
- Liu, C. (2017). The theory and application of space microbiology: China’s experiences in space experiments and beyond. Environmental microbiology, 19(2), 426-433.
- Liu, Y., Xie, G., Yang, Q., & Ren, M. (2021). Biotechnological development of plants for space agriculture. Nature Communications, 12(1), 1-3
- Cover Image Credit: Shujianyang