Chinese scientists have found a gene that plays a crucial role in helping rice adapt to low soil nitrogen and may be used to breed high-yield rice varieties with reduced nitrogen fertilizer use.

 

Nitrogen fertilizer plays an indispensable role in increasing crop yields, but it poses a severe threat to ecosystems. Scientists have been trying to breed new crop varieties with high nitrogen use efficiency (NUE) for agricultural production and environmental protection.

 

Researchers from the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences performed genome analysis on 110 seed stocks of cultivars (also called germplasm) collected from 52 countries and regions.

 

These seed stocks are local varieties grown by farmers globally before the popularization of modern high-yield rice varieties, that is, before the large-scale application of nitrogen fertilizer. They serve as a resource for diverse natural genes and traits that help breed new rice varieties.

 

By analyzing global soil nitrogen content data, the researchers found a strong correlation between the variants of a gene called OsTCP19 and global soil nitrogen-content distribution. OsTCP19-H, the high NUE version, was highly preserved in rice types grown in nitrogen-poor regions but has been lost in rice types grown in the nitrogen-rich areas.

 

OsTCP19-H was also highly prevalent in wild rice, which was grown in natural soil without artificial fertilizer. Among the modern rice varieties grown in China, it has been largely lost.

 

Further studies have shown that breeding high-yield crops with decreased nitrogen input can be realized by bringing OsTCP19-H back to modern cultivars. It can improve nitrogen use efficiency by 20 to 30 percent under conditions of reduced nitrogen supply.

 

The research findings have been published in the latest issue of Nature. According to experts, the research is expected to help find a solution to reduce fertilizer use without sacrificing food production. (Xinhua)