Plasma protection for rice crops

May 9, 2017, Tohoku University

Diseased rice seeds treated with atmospheric plasma show significant improvement and growth, offering a potential tool to protect rice crops from fungus and blight. A team from Tohoku University in Japan found that immersing infected rice seeds in hot water and then irradiating them with plasma reduced infection rates between 60 and 90 percent.

Plasma is the fourth state of matter along with solid, liquid and gas. It is a cloud of electrons that creates positive and negative ions, as well as neutral atoms. Plasma is emerging as a disinfectant in a variety of applications, including wounds and crops. It is used to sterilize crops after the harvest, where there is little concern about damaging living cells.

The Tohoku team, led by Professors Hideki Takahashi and Toshiro Kaneko, tested the effects of irradiation on healthy rice seeds, on rice seeds infected with bakanae disease caused by the fungal pathogen Fusarium fujikuroi, and on seeds infected by bacterial seedling blight, caused by Burkholderia plantarii.

The two diseases are major threats to worldwide. For example, Japan has reported 20 to 50 percent yield losses due to bakanae, and the United States has experienced 40 percent yield loss due to B. plantarii.

Often, rice seeds are treated in 60°C hot water for ten minutes to kill any bacteria before cultivation in greenhouse nurseries. However, if the rice is not left in the scalding water long enough or if the water is not quite hot enough, bacteria survives and can inhibit growth.

The team found the most effective way to reduce disease rates was the bath followed by plasma irradiation. There was no damage to the seeds, which germinated and grew like healthy seedlings.

"The combination of immersion and plasma irradiation of seeds seems to provide an excellent pest integrated management system to reduce risks to human health and the environment by minimizing the use of chemical pesticides," the researchers conclude in their study recently published in the journal Plant Pathology. How, exactly, the plasma treatment helps suppress the diseases remains a mystery. The researchers suspect that reactive oxygen compounds generated by irradiation play a role, but this requires further study.

Explore further: Mississippi entomologists report on benefits of neonicotinoid seed treatments on rice

More information: Management of bakanae and bacterial seedling blight diseases in nurseries by irradiating rice seeds with atmospheric plasma, Ochi, A., Konishi, H., Ando, S., Sato, K., Yokoyama, K., Tsushima, S., Yoshida, S., Morikawa, T., Kaneko, T. and Takahashi, H. Plant Pathol, 66: 67-76. DOI: 10.1111/ppa.12555

Related Stories

Scientists discover how arsenic builds up in plant seeds

December 22, 2015

Researchers from FIU's Herbert Wertheim College of Medicine Barry P. Rosen and Jian Chen, both from the Department of Cellular Biology and Pharmacology, are part of an international team that has identified how arsenic gets ...

German giants Bayer, BASF team up on GM rice

December 16, 2010

German chemicals giants Bayer and BASF said Thursday they were teaming up to produce genetically modified rice seeds, technology than can boost yields but which is criticised by environmentalists.

Recommended for you

Galactic center visualization delivers star power

March 21, 2019

Want to take a trip to the center of the Milky Way? Check out a new immersive, ultra-high-definition visualization. This 360-movie offers an unparalleled opportunity to look around the center of the galaxy, from the vantage ...

Ultra-sharp images make old stars look absolutely marvelous

March 21, 2019

Using high-resolution adaptive optics imaging from the Gemini Observatory, astronomers have uncovered one of the oldest star clusters in the Milky Way Galaxy. The remarkably sharp image looks back into the early history of ...

When more women make decisions, the environment wins

March 21, 2019

When more women are involved in group decisions about land management, the group conserves more—particularly when offered financial incentives to do so, according to a new University of Colorado Boulder study published ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.