The conserved nematode pheromone ascr#18 primes plant immunity

Authors: MANOHAR, MURLI - Boyce Thompson Institute; SISTENICH, ANDREA - Rwth Aachen University; KOCH, ALINE - Justus-Liebig University; BABY, SHINE - University Of Kentucky; CHEN, SHIYAN - Cornell University; KUMARI, ANSHU - Boyce Thompson Institute; LUNA, EMILY - Colorado State University; MANOSALVA, PATRICIA - Boyce Thompson Institute; LEACH, JAN - Colorado State University; Wang, Xiaohong; KACHROO, AARDRA - University Of Kentucky; KOGEL, KARL-HEINZ - Justus-Liebig University; CONRATH, UWE - Rwth Aachen University; SCHROEDER, FRANK - Boyce Thompson Institute; KLESSIG, DANIEL - Boyce Thompson Institute

Submitted to: Communications Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/24/2026
Publication Date: 5/6/2026
Citation: Manohar, M., Sistenich, A., Koch, A., Baby, S., Chen, S., Kumari, A., Luna, E., Manosalva, P.M., Leach, J., Wang, X., Kachroo, A., Kogel, K., Conrath, U., Schroeder, F., Klessig, D.F. 2026. The conserved nematode pheromone ascr#18 primes plant immunity. Communications Biology. https://doi.org/10.1038/s42003-026-10211-1.
DOI: https://doi.org/10.1038/s42003-026-10211-1

Interpretive Summary: The relationship between plants and pathogens in the environment is a complex process that profoundly impacts agricultural and environmental sustainability. In plants, defense priming increases plant defense responses, leading to extended protection against pathogens with minimal fitness costs. It is thought that alteration of gene expression due to changes in chromatin structure plays a central role in defense priming. However, the precise molecular mechanisms remain elusive. Using the model plant Arabidopsis, we showed that ascr#18, a pheromone secreted by plant-parasitic nematodes, can prime defense genes for enhanced expression upon pathogen challenge, therefore conferring long-term protection against pathogen infection. We further provided compelling evidence for the efficacy of ascr#18 in priming defense responses across several crop species including corn, soybean, wheat, and rice. The practical applicability of ascr#18 in agriculture was demonstrated through successful field trials conducted on major crops, including corn, soybean, and wheat. Together, this study provides further insights into the mechanisms and efficacy of ascr#18-mediated plant defense priming, laying the foundation for the development of novel strategies for crop protection and sustainable agriculture in the context of integrated pest management practices.

Technical Abstract: Defense priming enhances induced plant immune responses, providing extended protection against pathogens with minimal fitness costs. Epigenetic remodeling-mediated transcriptional reprogramming is presumed to play a central role in defense priming, yet the precise molecular mechanisms remain elusive. Here, we demonstrate in Arabidopsis thaliana that ascr#18, a pheromone secreted by plant-parasitic nematodes, primes immune genes for enhanced expression upon pathogen challenge, conferring long-term protection even with seed treatment. Associated with this priming and sustained protection is the formation of open chromatin in the regulatory regions of these genes. The ascr#18-mediated defense priming, and disease protection is compromised in Arabidopsis mutants defective in leucine rich repeat (LRR)-receptor-like kinases. These findings offer further insight into the molecular basis of defense priming. In addition, we document ascr#18’s efficacy under field conditions, thus demonstrating the potential of the technology to reduce the usage of harmful synthetic chemical pesticides and protect crops from damaging pathogens, thereby promoting environmental sustainability.