International first! China's space station grows rice seeds, "space seeds" have arrived in Beijing

On December 4, the return capsule of the Shenzhou XIV manned spacecraft landed successfully at the Dongfeng landing site. The third batch of space science experiment samples of the manned space station that descended with the capsule were delivered to the space application system at the landing site, including 3 biological sample cold packs and 1 containerless sample bag.

Image provided by Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, and Center for Space Applications, Chinese Academy of Sciences.

The samples were successfully transported to the Space Application Engineering and Technology Center of the Chinese Academy of Sciences on the 5th. After inspection and confirmation that the returned samples were intact, the samples were successfully handed over to relevant experimental scientists. Among them was the world's first rice seeds obtained in orbit after 120 days of cultivation and growth in space.

Rice seeds grown in space for the first time

Rice is the main food crop for humans and the main candidate food crop for the life support system of future manned deep space exploration. Using space microgravity to breed rice is one of the important directions of space botany research. Seeds are not only food for humans, but also the carrier for breeding the next generation of plants. If humans want to survive in space for a long time, they must ensure that plants can complete the alternation of generations in space.

Previously, only Arabidopsis, rapeseed, pea and wheat had been cultivated from seed to seed in space. In the Chinese space station, the "Molecular Mechanism of Flowering Regulation in Higher Plants under Microgravity Conditions" project targeted rice and Arabidopsis.

During the Shenzhou-14 crew's stay in orbit, the rice and Arabidopsis seeds underwent 120 days of space cultivation and growth in the Chinese space station, starting with the injection of nutrient solution on July 29 and ending on November 25, completing the entire development process from seed germination, seedling growth, flowering and seeding. This is the first rice cultivation experiment completed throughout its life cycle in the world.

During the mission, the astronauts collected samples three times in orbit, including rice samples at the booting stage, Arabidopsis samples at the flowering stage, and rice and Arabidopsis seed maturity samples. After collection, the flowering or booting stage samples were stored in a low-temperature storage cabinet at minus 80 degrees Celsius, and the seed maturity samples were stored in a low-temperature storage cabinet at 4 degrees Celsius.

The on-orbit experimental samples of rice and Arabidopsis were placed in three biological sample cold packs and returned to Earth with the spacecraft. Later, scientists will conduct molecular biology, cytology and metabolism analysis on the returned samples. Through detection and analysis, they will analyze the laws and molecular basis of the effects of space microgravity on Arabidopsis and rice, and provide a theoretical basis for further creating crops that adapt to the space environment and developing and utilizing space microgravity environment resources.

Rice blooms earlier in space

The growth of rice in space is a key concern for researchers. The many agronomic traits of rice grown in the microgravity environment of the space station are different from those on the ground.

The plant type became looser in space, the dwarf rice became shorter, and the height of the tall rice was not significantly affected; the flowering time of rice in space was slightly earlier than that on the ground, but the filling time was extended by more than 10 days; most of the glume could not close. Flowering time and glume closure play an important role in ensuring the full reproductive growth of plants and obtaining high-yield and high-quality seeds. Researchers will use the returned samples for further analysis.

In addition, the astronauts also conducted a regenerated rice experiment in the space station and obtained regenerated rice seeds. The rice plant regenerated two rice ears only 20 days after pruning. Researchers believe that this provides new ideas and experimental evidence for the efficient production of space crops. This technology can greatly increase the rice yield per unit volume. It is also the first time that the regenerated rice technology has been tried in space internationally.

Arabidopsis thaliana also bloomed successfully in space, and researchers conducted the first study on the key genes of the space biological clock regulating photoperiodic flowering. In the future, they will further use the returned materials to conduct in-depth analysis of the molecular basis of Arabidopsis thaliana's adaptation to the space environment.

Stable operation of containerless material test cabinet

The containerless sample bag returned this time also contains 4 boxes of containerless material experimental samples. These are samples produced by experiments conducted in the space station's containerless material experiment cabinet in a microgravity environment.

The containerless material experiment cabinet is the first experimental facility of its kind in China and the second in the world to be successfully operated in orbit. So far, it has achieved stable operation in orbit for more than 590 days, successfully completed in-orbit experiments on 7 boxes of material samples, and successfully heated 73 samples.

The Chinese Academy of Sciences stated that through long-term in-orbit experiments, the space application system has broken through and mastered a series of key technologies, acquired a large amount of important scientific data, revealed a number of new phenomena in space experiments, and through ground analysis and research, produced some preliminary results and published a number of papers in internationally renowned top journals.

Subsequently, scientists will continue to accelerate the research on the deep supercooling solidification process of new metal alloys and the measurement of thermophysical properties in order to obtain the key conditions for high-performance preparation technology on the ground and guide the preparation of new ground materials.

Source: Beijing Daily