Genetic modification improves biological nitrogen fixation in rice

Researchers at the University of California and Bayer Crop Science appear to have discovered a way to improve biological nitrogen fixation (BNF) in cereal crops.

Using a new technique, rice plants were modified to increase the production of compounds that stimulate biofilm formation in diazotrophic bacteria in the soil. Furthermore, they promote bacterial colonization of plant tissues and improve biological nitrogen fixation with increased grain yield at limiting nitrogen levels in the soil.

The technique was described in several steps in a scientific article published in the Plant Biotechnology Journal.

In summary, researchers performed chemical screening to identify plant-produced compounds that induce biofilm formation in nitrogen-fixing bacteria.

They discovered that apigenin and other flavones induce biological nitrogen fixation.

Then, they edited genes with the aim of degrading apigenia in rice. Thus, the plant's apigenin levels increased; and root exudation.

As a result, under soil nitrogen limiting conditions, the modified rice plants showed higher grain yield.

The scientists explain that the results indicate the manipulation of the flavone biosynthetic pathway as a viable strategy for inducing biological nitrogen fixation in cereals.

The team is made up of Dawei Yan (Department of Plant Sciences, University of California); Lauren C. Cline (Bayer Crop Science, St. Louis); Reedmond Y. Fong (Department of Nutrition, University of California); Javier I. Ottaviani (Department of Nutrition, University of California); Howard-Yana Shapiro (Department of Plant Sciences, University of California); Eduardo Blumwald (Department of Plant Sciences, University of California).

The article can be read, in English, at the link below: