Daily Weird News Report
A chemical signal associated with nematodes may give plants an advance warning system against disease, according to research from the Boyce Thompson Institute published in Communications Biology.
The compound, called ascaroside 18 or ascr#18, belongs to a class of nematode pheromones known as ascarosides. Researchers investigated whether plants could recognize these molecules as signs of a potential nematode threat and adjust their defenses.
Their experiments found that treating plants with ascr#18 increased resistance to a broad range of pathogens, including bacteria, viruses, fungi and nematodes. The treatment did not appear to trigger a full immune response immediately. Instead, it placed plants in what the researchers describe as a primed state, allowing them to react more quickly and robustly once infection occurred.
That distinction matters because activating a full immune response can divert energy away from growth and development. The researchers reported that ascr#18 provided enhanced protection without the same apparent fitness cost.
The study identified changes at the chromatin level as part of the process. According to the research team, these changes make defense-related genes more accessible to the machinery that activates them, creating a longer-lasting form of immune memory.
The effect was tested in agriculturally important crops. In field applications, spraying ascr#18 onto leaves reduced fungal disease severity and improved yields in corn and soybean, according to the report. Researchers also found that soaking seeds in a solution containing the compound was enough to prime plants for stronger defenses later in their development.
A seed treatment could be particularly useful because it may provide protection from the beginning of the growing season rather than requiring application shortly before or during a pathogen attack. The researchers also described ascr#18 as inexpensive to produce and usable on a wide range of crops, although the report concerns the study’s findings and potential commercial applications rather than an established farming product.
The work was led by researchers from the Boyce Thompson Institute and RWTH Aachen University. The authors said the approach could offer an alternative to strategies aimed directly at pathogens, which can adapt and develop resistance.
