EAST LANSING, Mich. Back-to-back scientific papers are offering a revolutionary look at the battlefield on which plant diseases are fought and often lost to bacteria.
The laboratory of Sheng Yang He at Michigan State University has changed the textbook description of a plant's surface terrain and is unveiling new knowledge of how bacterial pathogens invade plants and take hold. The most recent paper, published in the Sept. 8 edition of Cell, redefines the role of the plant's pores in defense against invading bacteria and how some bacteria can overpower plants.
Last month, in Science Magazine, the lab outlined a better understanding of how bacteria set up camp and destroy the plant's ability to fight infection.
The work was funded by the National Institutes of Health and the U.S. Department of Energy and supported by the Michigan Agricultural Experiment Station.
"We've known for 100 years that bacterial pathogens cause illness in crops, yet we still don't understand how they produce disease," said He, a professor of plant biology, plant pathology, and microbiology and molecular genetics. "It's very frustrating. How does this little thing do such great damage to plants?"
But this summer, Maeli Melotto, a research associate, and Bill Underwood, a graduate student, in He's laboratory, shed light on the behavior of one the plant's first lines of defense against disease. Pores called stomata are like tiny mouths that open and close during photosynthesis, exchanging gases. In sunshine, the stomata open. In darkness, they close to conserve water.
It has been assumed that these tiny ports were busy with their photosynthesis business and were merely unwitting doorways to invading bacteria on a plant's surface. Melotto and Underwood, however, have discovered that stomata are an intricate part of the plant's immune system that can sense danger and respond by shutting down.