Crop Biotech Update

Study Reveals the Defense Roles of Soybean GmAFS Gene Against Nematodes and Insects

December 1, 2016

Plant terpene synthase genes (TPSs) have various roles in biological processes. University of Tennessee's Jingyu Lin, together with researchers from various research institutions worldwide, characterized a member of the soybean TPS gene family, GmAFS. The team also studied the role of GmAFS in defense against nematodes and insects of soybean (Glycine max).

GmAFS was found to be closely related to (E,E)-α-farnesene synthase gene from apple. The expression of GmAFS in a soybean cyst nematode-resistant variety was significantly induced by the infection. However, its expression in a SCN-susceptible soybean was not changed by the same infection. Transgenic hairy roots overexpressing GmAFS were generated in an SCN-susceptible soybean line to test its role. The transgenic lines showed significantly higher resistance to SCN, indicating that GmAFS contributes to SCN resistance.

In soybean leaves, the expression of GmAFS was found to be induced by Tetranychus urticae (two-spotted spider mites) as well as exogenous application of methyl jasmonate. Further analysis revealed that soybean plants infested with T. urticae emit a mixture of volatiles with (E,E)-α-farnesene as one of the most abundant components.

This study reveals the GmAFS defense roles in both below-ground and aboveground organs of soybean.

For more information, read the article in Plant Biotechnology Journal.