Fungal threats to turfgrass: a battle for the green! 🌱🌱🌱
Fungal infections are a gardener's worst nightmare, and they can strike any plant, even the beloved turfgrass on golf courses and lawns. Imagine your vibrant garden, only to find it suddenly plagued by brown spots and withered leaves. It's a scenario no plant lover wants to face.
Dollar spot disease, a fungal menace, poses a similar challenge to blade grasses. Picture circular spots of dead turf, resembling silver dollars, spreading across lush green lawns. This costly problem demands attention, with an average U.S. golf course spending upwards of $35,000 annually to manage it. The $40 billion turfgrass industry needs innovative solutions, and biological treatments offer a promising ray of hope.
Enter UD1022, a unique bacterium developed by the University of Delaware. Discovered by plant biologist Harsh Bais and his team, this beneficial strain of Bacillus subtilis is a plant's best friend, boosting its defenses and offering a range of benefits, from moisture retention to stronger root-to-shoot growth. In previous studies, UD1022 showed promise in controlling the growth of dollar spot fungus, Clarireedia jacksonii, on turfgrass.
But here's where it gets controversial... In a recent study published in Plant Stress, the research team delved deeper into the effects of UD1022 on dollar spot. They found that while UD1022 can biologically control the growth of dollar spot in turfgrass, it's a delicate dance. The bacterium needs to be in direct contact with the fungus to antagonize it effectively. Applying UD1022 to the roots alone isn't enough to ward off infection in the leaves, as if there's a communication breakdown between the roots and the leaves.
"It's like UD1022 needs to be right there, face-to-face with the dollar spot fungus, to do its job," Bais explained. "And it has to be alive and kicking!"
The findings have implications for the formulation and application of biological treatments for dollar spot disease. Bais and his team are using these insights to develop a more sustainable disease management strategy, combining UD1022 with existing approaches. UD1022 also increases drought tolerance in turfgrass, showcasing its dual role in plant health.
"Biologicals like UD1022 are powerful, but they're not a one-size-fits-all solution. We need to keep evolving our approach," Bais emphasized.
Bais is taking his research further, aiming to develop a pipeline for biologicals like UD1022. During his sabbatical work at Pacific Northwest National Laboratory (PNNL) in 2027, he plans to explore a synthetic microbial community composed of 10-15 beneficial microbes isolated over 21 years. The biggest challenge? Evaluating the persistence of these microbes on the root surface, as root colonization is key to triggering plant health benefits.
"Using a champion root colonizer like UD1022 in a microbial consortium could be a game-changer. We'll be testing its compatibility and implications on plant and soil health," Bais said.
The future work will involve using this synthetic microbial consortium in turfgrass and other staple monocots like sorghum and corn, simulating real-world environmental scenarios, such as drought and dollar spot together. Bais and his team are interested in understanding how plants respond to multiple stresses simultaneously and how microbial communities can help.
"Plants don't grow in isolation, and the compatibility of microbes is crucial. This paper is just the beginning of our journey to uncover the secrets of plant-microbe interactions," Bais concluded.
Co-authors on this groundbreaking research include Bais, Charanpreet Kaur (lead author and research associate in the Bais lab), and Erik Ervin, professor of turfgrass and horticultural systems and associate dean in UD's College of Agriculture and Natural Resources.
