Bacterially secreted immunostimulants to protect plants against pathogens

Unmet Need: Effective strategies to protect plants from root knot nematode

Root-knot nematodes (RKN, Meloidogyne spp.) are major agricultural pests on a global scale and can cause billions of dollars in yield loses each year. The temperate root-knot nematode Meloidogyne chitwoodi is endemic to the potato growing regions of the Pacific Northwest of the USA, as well as areas of Europe, Asia, and Africa. This species is important in potato production because it can infect the tubers, causing unsightly galling and brown spots to form under the tuber skin. Commercially available potato cultivars do not have natural genetic resistance to M. chitwoodi and Growers rely heavily on costly nematicides. There is a need to develop alternative methods for root-knot nematode control.

The Technology: Use of Peptide elicitor and its delivery through Bacillus subtilis

Researchers at WSU have generated a transgenic rhizobacteria Bacillus subtillis that secretes a potato defense peptide: StPep1. The engineered bacteria were confirmed to produce and secrete detectable levels of the plant elicitor peptide. Inoculation of engineered Bacillus onto potato roots, showed StPep1-mediated resistance against root-knot nematodes. This work would allow researchers to modify Bacillus spp. to secrete defense peptides against a variety of plant pathogens.


  • Pathogen management to control highly contagious diseases in roots and tuber crops.


  • This strategy would be applicable against a variety of plant pathogens and against different plant diseases for many different crop species.
  • This could minimize dependence on harmful chemicals/pesticides.
  • Bacillus spp. doesn’t affect the root mass. It has neutral or positive effects on early plant growth.
  • The approach is environmentally friendly and inexpensive.

Patent Information:

Provisional application filed

Learn More

Deah McGaughey
Technology Licensing Associate
Washington State University
(509) 335-9502
Reference No: TECH-20/3305


Cynthia Gleason
Lei Zhang

Key Words

Agriculture and Plant Sciences