(The picture shows the primary rice and ratooning rice of space rice, showing the phenotype of open panicles and glumes of space rice.) At 20:09 on December 4, Beijing time, the return capsule of the Shenzhou XIV manned spacecraft landed successfully at the Dongfeng landing site. On the same day, the third batch of space science experiment samples of the manned space station descending with the cabin were delivered to the space application system at the landing site, and returned to Beijing in the early morning of the next day. They were successfully transported to the Space Application Engineering and Technology Center of the Chinese Academy of Sciences. The space application system general and relevant experimental personnel checked the basic status of the experimental samples, and after confirming that the returned samples were in good condition, they were successfully handed over to relevant experimental scientists. The returned samples include three biological sample cold packs and one containerless sample bag. Three biological sample cold packs contain rice and arabidopsis experimental samples, and four containerless material experimental samples are contained in the containerless sample bags. Rice and Arabidopsis seeds have experienced a 120 day life cycle. Rice is the main food crop for human beings, and also the main candidate food crop for the future manned deep space exploration life support system. Rice breeding using space microgravity is also one of the important directions of space botany research. If human beings want to survive in space for a long time, they must ensure that plants can successfully reproduce seeds in space. Previously, only Arabidopsis, rape, pea and wheat were cultivated from seed to seed in space, while rice, the main food crop, had not been cultivated in space for the whole life cycle of rice. In the life science project of China's space station, Zheng Huiqiong, the research team of the Center for Excellence and Innovation in Molecular Plant Science of the Chinese Academy of Sciences, undertook the "molecular mechanism of flowering regulation of higher plants under microgravity conditions", and carried out the space culture experiment of rice in the full life cycle from seed to seed for the first time in the world. At the same time, flowering is the premise of seed production. The research team also systematically studied the impact of space microgravity on plant flowering using the model plant Arabidopsis. The project has carried out experiments for 120 days in orbit, and completed the whole life cycle of seed germination, seedling growth, flowering and seed setting of Arabidopsis and rice. During this period, astronauts carried out three sample collection on orbit, including rice sample collection at booting stage on September 21; Samples were collected at the flowering stage of Arabidopsis on October 12 and at the mature stage of rice and Arabidopsis seeds on November 25. After collection, the samples at flowering or booting stage are stored in a low-temperature storage cabinet at minus 80 ℃, and the samples at seed maturity stage are stored in a low-temperature storage cabinet at 4 ℃. On December 4, the sample returned to the ground with Shenzhou XIV. After the samples are handed over in Beijing as planned, they are transferred to the Shanghai laboratory for further testing and analysis. The main experimental contents of this space project include: the whole life cycle cultivation experiment of rice from seed germination, seedling growth, heading and seed setting was completed on orbit, and the image was acquired for analysis; After cutting, the space ratooning rice was successfully cultivated and produced mature seeds (second crop); Image observation and analysis of response of Arabidopsis seed germination, seedling growth and flowering key genes regulated by different biological clocks to space microgravity were completed on orbit, and samples were collected on orbit. Preliminary experimental findings