Wang Kejian’s team at the China Rice Research Institute reported development of
a one-line hybrid rice, Yixi No.1, achieving stable cloning efficiency above 99%
and normal fertility; the study was published July 21 in the journal Vita. By
contrast, China’s widespread three-line and two-line hybrid systems suffer
genetic segregation and cannot be used to retain seed, forcing annual production
from male-sterile and restorer lines — a process the team says is technically
demanding, higher risk and typically drives hybrid seed costs to more than 10x
conventional rice seed. Experts note hybrid rice has been indispensable to
China’s and global food security.