After returning to Earth from a three-week lunar voyage with the Chang’e 5 spacecraft last December, some 1,600 rice seeds sprouted in a greenhouse in southern China’s Guangdong province, with scientists hoping the extraterrestrial exposure could help create new plant varieties.
On Monday, scientists at South China Agricultural University’s National Engineering Research Center of Plant Space Breeding transplanted the seedlings to an open field. According to domestic media, these plants, which traveled farther than any others in the history of China’s space program, would be ready for harvest in June.
Researchers hope the experiment in “space-induced mutation breeding” will create new types of rice. Guo Tao, deputy director of the plant space breeding lab, told state-backed newspaper Science and Technology Daily that the extreme environment of deep space “plays a key role in creating and breeding new varieties.”
A young scientist attempts to mark a field containing seeds from the Chang’e 5 spacecraft in Guangzhou, Guangdong province, March 29, 2021. Liu Dawei/Xinhua
Scientists commonly use radiation — including types found in outer space — to generate mutations in plants. Lu Baorong, director of the Department of Ecology and Evolutionary Biology at Fudan University, told Sixth Tone that the complex extraterrestrial environment can induce unique changes in a plant’s genes that might not otherwise appear on Earth.
Some mutations could lead to traits that are beneficial to humans, such as bigger fruits or higher tolerance for drought, said Lu, who was not involved in the space rice project.
China began space-induced mutation breeding experiments in the 1980s. Using satellites and spacecraft, the country has sent a variety of plants into space, including rice, tomatoes, and peppers. Dozens of types of plants later entered the market. In 2018, more than 2.4 million hectares of land in China was used to grow space crops, according to state media.
In 2019, China’s Chang’e 4 mission brought cotton seeds to the far side of the moon. Pictures sent back from the lunar probe showed that these seeds sprouted in a sealed chamber on the Chang’e 4 lander but died after nightfall, when the temperature plummeted.
In the 1970s, the U.S. space agency NASA loaded its Apollo 14 lunar probe with tree seeds and planted them across the country after the spacecraft returned. Three decades later, the agency said these “moon trees” showed “no discernable differences” from regular, earthbound trees.
While the space environment could cause genetic changes in plants, Lu cautioned that uncertainties remain, such as their effects on the environment and food safety. As for what you might get each time, that “depends purely on luck.” So far, he said, China has not set safety regulations for products subject to space-induced mutation experiments.
“This is more of a gimmick to me. They make it sound like everything from space is better,” Lu said. “But humans know so little about mutations from outer space.”
The scientist added that whether space-induced mutations might be problematic requires further research. “I don’t think this approach will become mainstream in crop breeding because there are just so many variables that we can’t control,” he said. “Why don’t we trust the biotechnologies we already have on Earth?”
Editor: David Paulk.
(Header image: Scientists manually transplant rice seedlings from a nursery to an experimental field in Guangzhou, Guangdong province, March 29, 2021. Liu Dawei/Xinhua)