Chinese scientists crack sterility code in hybrid rice, raising hopes for healthier, high-yield crops
- Researchers unlock secrets of how ‘killer’ and ‘guardian’ genes cause infertility in rice plants
- Study paves way for ‘super hybrid’ of Japonica and Indica subspecies, which could increase yields by over 15 per cent, according to co-author
After 13 years of research, a team from the Crop Science Research Institute of the Chinese Academy of Agricultural Sciences (CAAS) and Nanjing Agricultural University, led by academician Wan Jianmin, overcame this rice breeding challenge. Their findings were published in the peer-reviewed journal Cell on Wednesday.
The team first identified the gene series that causes pollen sterility in Japonica-Indica rice hybrids.
They found that two closely linked genes act together – one as a “killer” and the other a “guardian”. All of the hybrid offspring inherit a killer gene, which harms the pollen, causing sterility, while only some offspring inherit a guardian gene that prevents the killer from doing harm.
“The work amounts to revealing how the killer works,” said Wu Chuanyin, a professor at CAAS and co-author of the paper.
The killer disrupts the energy production function of a core protein in the mitochondria, the energy factories of cells, leading to sterile pollen.
The guardian interacts with the killer, re-routing it to another cell factory where it is broken down, eliminating the killer gene and ensuring normal pollen development.