Chinese Scientists Develop High-Protein Maize Varieties Through Gene Discovery
Chinese scientists have identified two crucial genes linked to high protein content in maize and successfully developed high-protein maize varieties, marking a significant advance in efforts to address China’s animal feed protein shortage. The findings were published online on Wednesday in the academic journal Nature.
Researchers found that wild maize can contain protein levels of up to 30 per cent. However, more than 9,000 years of domestication and modern breeding resulted in the loss of many protein-related genes. According to Wu Yongrui, deputy director of the Center for Excellence in Molecular Plant Sciences (CEMPS) of the Chinese Academy of Sciences (CAS), breeders historically did not specifically select for protein content, leading to the disappearance of these valuable genetic traits in most modern maize varieties.
First Breakthrough In High-Protein Gene Research
In 2022, a research team led by Wu identified the first high-protein gene, THP9-T, from wild maize. This discovery enabled researchers to achieve an initial increase in protein content across major domestic maize cultivars. Nevertheless, substantially improving maize protein levels remained a complex scientific challenge.
The team continued its research and eventually identified a second high-protein gene, THP3-T. This discovery represented another important step towards developing maize varieties with enhanced nutritional value.
Field Trials Deliver Promising Results
Multi-year and multi-location field trials demonstrated the effectiveness of THP3-T. The gene increased kernel protein content in inbred maize lines from 10 per cent to more than 13 per cent without reducing yield. In addition, it improved whole-plant protein content.
Researchers also observed that maize carrying the gene maintained strong growth while remaining protein-rich under reduced fertiliser conditions. As a result, the gene offers potential benefits for both productivity and resource efficiency.
Wu explained that these characteristics could contribute to more sustainable maize production while helping to meet growing demand for protein-rich animal feed.
Combined Genes Produce Stronger Effect
Further analysis revealed that combining THP3-T and THP9-T generated an exceptional synergistic effect. Together, the two genes increased kernel protein content in inbred maize lines from 10 per cent to 15 per cent.
This improvement significantly exceeded the gains achieved by either gene independently. Consequently, the combined use of both genes represents a major breakthrough in maize breeding.
The research team applied marker-assisted breeding technology to improve more than 80 parental lines used in major maize cultivars across China. Through this precise breeding approach, researchers increased protein content in these lines to more than 14 per cent.
Improvement Of Major Maize Cultivars
The team also achieved notable results with Zhengdan958, China’s most widely cultivated maize hybrid. Researchers successfully increased the hybrid’s kernel protein content from 8.5 per cent to more than 12 per cent.
These developments highlight the potential of advanced breeding technologies to enhance the nutritional quality of maize while maintaining agricultural performance. The discoveries may provide new opportunities to strengthen domestic protein supplies and support the livestock sector through improved feed resources.
With inputs from Reuters
