Fungal infections are threatening global food security

  

The 8-spore asci of Morchella elata, viewed with phase contrast microscopy

Researchers have warned of the 'devastating' impact that fungal disease in crops will have on global food supply. This is unless governments and agencies across the world come together to find new ways to combat infection.

 

University of Exeter scientists estimate that global growers lose between 10 and 23 per cent of their crops to fungal infection each year. An additional 10-20 per cent is lost post-harvest. The researchers predict these figures will worsen as global warming means fungal infections are steadily moving polewards, meaning more countries are likely to see a higher prevalence of fungal infections damaging harvests.

 

 

As an example, growers have already reported wheat stem rust infections -- which normally occur in the tropics -- in Ireland and England. The experts also warn that tolerance to higher temperatures in fungi could increase the likelihood of opportunistic soil-dwelling pathogens to hop hosts and infect animals or humans.

 

Food security is also expected to encounter unprecedented challenges as rising populations mean more demand. Across the five most important calorie crops of rice, wheat, maize (corn), soya beans and potatoes, infections cause losses which equate to enough food to provide some 600 million to 4 billion people with 2,000 calories every day for one year.

 

The research highlights a "perfect storm" which is causing fungal infections to spread rapidly. Among the factors is the fact that fungi are resilient, remaining viable in soil for up to 40 years, with airborne spores that can travel between continents. Added to this, they are extremely adaptable, with "phenomenal" genetic diversity between and among species.

 

Modern farming practices entail vast areas of genetically uniform crops, which provide the ideal feeding and breeding grounds for such a prolific and fast-evolving group of organisms.

 

Fungi are well equipped to evolve beyond traditional means to control their spread. The increasingly widespread use of antifungal treatments that target a single fungal cellular process means fungi can evolve resistance to these fungicides, so that they are no longer effective. This forces farmers to use ever-higher concentrations of fungicide in a bid to control infection, which can accelerate the pace of resistance developing.

 

Farming practices and new anti fungicides may hold the key to change. The authors argue that protecting the world's crops from fungal disease will require a far more unified approach, bringing together farmers, the agricultural industry, plant breeders, biologists, governments, policymakers and funders.

 

The research reference is:

 

Eva Stukenbrock, Sarah Gurr. Address the growing urgency of fungal disease in crops. Nature, 2023; 617 (7959): 31 DOI: 10.1038/d41586-023-01465-4

 

Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (http://www.pharmamicroresources.com/)