Chinese scientists have identified two key genes associated with high protein content in maize and have bred high-protein varieties, which may offer a promising solution to food security. This was reported by
Science and Technology Daily, a TV BRICS partner.
A team led by Wu Yongrui and Wang Haihai at the Centre of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, has discovered a second high-protein gene in wild maize, Teosinte high protein 3 (THP3-T). This gene works synergistically with the previously identified THP9-T to significantly boost maize protein content.
Maize is the world’s most widely cultivated food crop, yet its protein content is low, at just 8 per cent. Wild maize is rich in protein, with levels reaching up to 30 per cent. However, during a domestication process spanning more than 9,000 years, these genes associated with high protein content were gradually lost. Only 2.1 per cent of modern maize varieties retain the THP3-T variant gene responsible for high protein content.
Field trials have shown that the THP3-T gene can increase the protein content of inbred maize grains from 10 per cent to over 13 per cent, while maintaining high nitrogen fixation efficiency even under low-nitrogen conditions. When the THP3-T and THP9-T genes are combined, the protein content of the inbred lines rises to 15 per cent.
“To date, the team has precisely improved over 80 parental lines of major domestic maize varieties, all of which now have protein contents of over 14 per cent,” noted Wu Yongrui, Deputy Director of the Centre of Excellence in Plant Molecular Sciences (CEMPS) at the Chinese Academy of Sciences.
This discovery reveals the molecular mechanisms underlying the formation of high-protein maize and opens up new avenues for replacing imported soya meal with high-protein maize.