Researchers at Texas A&M AgriLife Research have developed an innovative plant-based defense against two of the most destructive agricultural diseases in the U.S.-citrus greening and potato zebra chip.
Their breakthrough involves using naturally occurring antimicrobial peptides called defensins, derived from spinach, to bolster the plants’ own defenses.
Spinach defensins are small proteins that protect spinach plants from a broad range of pathogens.
Because these peptides are naturally present in a common leafy vegetable and deemed safe for human consumption by the U.S. Environmental Protection Agency, they offer a promising, eco-friendly alternative to synthetic pesticides.
The research team, led by plant molecular biologist Dr. Kranthi Mandadi, introduced these peptides into citrus trees and potato plants using a benign viral vector developed in collaboration with the University of Florida.
This delivery system targets the same tissues where harmful bacteria reside, enabling the peptides to reduce bacterial infection and disease symptoms effectively.
In citrus trees afflicted by citrus greening disease, treatment with spinach defensins resulted in up to a 50% increase in fruit yield after a single application, along with improved fruit quality and healthier plants.
Similarly, potatoes infected with zebra chip disease showed fewer symptoms, reduced bacterial presence, less tuber discoloration, and higher tuber counts when expressing these peptides.
This research highlights the potential of plant-derived peptides to enhance crop resilience and productivity. Dr. Mandadi envisions expanding this approach to other crops and combining multiple peptides to create broad-spectrum treatments, integrating them with pest management strategies to control insect vectors spreading these diseases.
With commercial development underway, including licensing agreements and EPA applications for use, spinach defensins could soon become a vital tool for growers to protect valuable plants and flowers from devastating diseases while supporting sustainable agriculture.
