Rice plays a significant role in the food chain for developed and developing countries alike. Rice is referred to as one of the most strategic commodities worldwide, as it offers food security in multiple countries. Rice is also considered a staple food for half of humanity, feeding more than 3.5 billion people globally. However, the rice crop faces a serious threat – rice blast disease.

Richard Wilson, associate professor in the Department of Plant Pathology at the University of Nebraska-Lincoln, studies rice blast, a fungal disease that significantly impacts rice production, with the goal of reducing rice blast development on the rice plant.

More specifically, the fungus attacks the plant and essentially takes all sugars, amino acids, etc. the plant needs to survive. Doing so also makes photosynthesis less efficient.

Rice blast looks like infected, tear-drop-shaped lesions on the plant where the leaves appear to have been burnt. However, it is fairly undetectable by the plant until it has completely overtaken the crop. Wilson is working to find a solution.

“We are working to create a long term, sustainable means of reducing rice blast to a manageable level, in a cost-effective way for use in the United States and deployed to developing countries as well,” Wilson said.

Rice blast can significantly lessen the yield for the rice crop, Wilson said. Given the rising worldwide population and the heavy reliance on rice as a food source, a lower yield is a serious concern to food security.  

Lost Rice Impacts Overall Health

Rice blast disease decreases crop yields, which means less rice harvested worldwide, Wilson said. Further, a limited amount of rice worldwide ultimately increases rice cost. However, many around the globe will not go without rice and will pay more to keep rice in their diet.

“Even with an increase cost of rice, people often will still spend money on rice and not on other foods that they would normally buy,” Wilson said. “They will not go without rice, regardless of cost.”

Paying more for rice may limit money available for healthier food options, such as fruits and vegetables. While this could be acceptable for adults, Wilson said the impact on children can be long-lasting.

“For children, a lost rice crop can have long-lasting developmental effects due to less access to vitamins from fruits and vegetables,” Wilson said. “In this way, there is a whole trickle effect to human health from losing a rice crop. It really is about food security for these parts of the world.”

Reducing rice blast disease in rice plants provides a much more secure crop by enabling farmers to grow healthy rice.

“Our goal is to provide a solid foundation for societies by enabling them to grow healthy rice,” Wilson said. “We want the options to be affordable for growers and when harvested, the rice to be affordable for consumers.”

Specifically, Wilson and his team study ways the rice blast pathogen - the fungus that is killing the plant called Magnaporthe oryzae – grows and develops in contact with the host plant. M. oryzae does not produce toxins, but rather destroys the plant once it gets into it.

This fungus can also overcome resistance and chemicals very rapidly, causing it to be the most devastating disease of cultivated rice.

Rice Economics & Sustainability

Rice blast is capable of wiping an entire field out, making the fungus not only a global food security threat, but also a threat to the global economy.

“Rice blast is able to destroy enough rice to feed approximately 70 million people worldwide,” Wilson said. “That much rice lost is a significant economic hit to rice producers.”

Wilson said that with current practices, rice blast still destroys 10% to 30% of each year’s world rice harvests.

In developed countries, like the United States and Japan, the economic hit of rice blast is insured, or farmers can afford to use fungicides to prevent it as much as possible. However, Wilson said in developing countries, the use of most fungicides is not an option, so a complete wipe-out of their harvest because of rice blast is detrimental. 

“We want to be able to deploy something into the field that reduces rice blast in a sustainable way – one that works for farmers across the globe,” Wilson said.

For more information, follow Wilson on Twitter @WilsonLab.