Biotech Updates

Chinese Scientists Identify Major Regulatory Gene in Rice

August 22, 2008

A few genes for hybrid sterility of indica and japonica, two subspecies of Asian cultivated rice (Oryza sativa L.), were identified by Prof. Qifa Zhang’s research group from Huazhong Agricultural University in China. The researcher cloned S5 gene, a major locus for indica–japonica hybrid sterility and wide compatibility. This finding may have important implications in rice genetic improvement and hybrid breeding.

The coexistence of indica–japonica hybrid sterility and wide-compatibility varieties (WCVs) is a unique phenomenon in the evolution of rice. Genetic differentiation between indica and japonica would have been enforced because of the reproductive barrier caused by S5-i (indica )/S5-j (japonica ). However, the wide-compatibility gene (WCG) provides an opposing force allowing for hybridization and gene flow between indica and japonica. With the discovery and molecular characterization of the WCGs, the overcoming of the hybrid sterility for improving rice productivity has become a reality.

The paper published by PNAS is available at