Peptide Holds Promise for Increasing Crop Yields without More Fertilizer

Molecular biologists from the University of Massachusetts Amherst (UMassAmherst) have discovered a "double agent" peptide in an alfalfa that promises to improve crop yields without increasing fertilizer use. The UMassAmherst team together with colleagues from the Noble Foundation, report that alfalfa appears to use an advanced process for putting nitrogen-fixing bacteria, rhizobia, to work more effectively after they are recruited from soil to fix nitrogen in special nodules on plant roots.

In alfalfa, the transformation of bacteria is called differentiation. NCR peptides found exclusively in the nodule, act on the bacteria in the differentiation process. The researchers discovered that one of these peptides, DNF4, also known as NCR211, supports nitrogen-fixing bacteria when inside the plant, and block free-living bacteria outside. The dual effect of DNF4/NCR211 may reflect a mechanism to ensure that the rhizobia stay in a properly differentiated state.

According to Dong Wang, professor of biochemistry and molecular biology at UM Amherst, discovering NCR211 peptides that maintain bacterial survival inside host cells may turn out to be a key factor in future efforts to improve legume crops without using more fertilizer, an important development for farming in developing countries.

For more information, read the news release from UMassAmherst.