Anthracnose Alert: How Bacteria Prime Fifth-Biggest Global Grain Crop Against Deadly Fungus
Anthracnose of Sorghum bicolor devastates crops of the drought- and heat-resistant cereal worldwide. Priming with rhizobacteria can boost the plants’ resistance and tolerance against a wide range of adverse conditions such as microbial attacks.
University of Johannesburg researchers decoded how priming enhances the ‘security system’ of plants for a much stronger, faster defense.
Using metabolomics and machine learning algorithms, they identified changes in the sorghum plant’s chemical response to fungal attack.
The low-cost approach can be used to counter other pathogens in economically important food crops.
Priming sorghum plants with friendly bacteria around their roots, can make their leaves more resistant to attacks from the Colletotrichum sublineolum fungus. Biofertilizers which contain these rhizobacteria are used commercially for sorghum and other crops.
In industry, these are called “plant-growth promoting rhizobacteria” or PGPR. Seeds can be coated with biofertilizers, and soil or plants can be sprayed with it.
But how and why priming works to defeat pathogens such as the CS fungus on cereal crops was unknown.
Priming with rhizobacteria can make a susceptible plant more tolerant and a tolerant plant more resistant to disease. This means that priming, or pre-conditioning, can enhance crop yields and reduce the use of fungicides. It is a promising, sustainable and low-cost option to get more effective resistance in real-world farming conditions, where many pathogens threaten food crops.