Beyond contact toxicity: Volatile and systemic nematode suppression by ‘Candidatus Pseudomonas auctus’ JDE115 in soybean
- 1School of Plant and Environmental Sciences, 328 Smyth Hall, 185 Ag Quad Lane, Virginia Tech, Blacksburg, VA 24061, United States
Abstract
Plant-parasitic nematodes such as soybean cyst nematodes (SCNs) (Heterodera glycines) and root-knot nematodes (Meloidogyne spp.) pose a significant threat to global soybean productivity. This study evaluated the multimodal biocontrol potential of ‘Candidatus Pseudomonas auctus’ JDE115, a soybean nodule-derived bacterium known for its plant growth-promoting properties. Greenhouse-based pot and split-root assays showed that JDE115 not only significantly improved soybean growth and nodulation but also suppressed SCN reproduction by over 90% locally and 85% systemically, indicating both direct antagonism and possibly induced systemic resistance. Volatile profiling using solid-phase microextraction gas chromatography–mass spectrometry identified dimethyl disulfide and 1-undecene as distinctive volatile organic compounds produced by JDE115. Bioassays with free-living nematodes demonstrated that 1-undecene elicits strong avoidance behavior and causes rapid mortality in nematodes in the absence of direct contact. Furthermore, a colorimetric picrate assay confirmed substantial hydrogen cyanide production by the bacterium. Additional tests revealed that JDE115 inhibits egg hatching and causes juvenile mortality through a combination of chemical toxicity and enzymatic degradation. Collectively, these findings establish JDE115 as a multifunctional plant growth-promoting rhizobacterium with potential nematicidal activity and broad biocontrol potential, underscoring its value as a next-generation microbial tool for integrated nematode management in soybean cultivation. To our knowledge, this is the first report demonstrating combined volatile-mediated and systemic suppression of SCN by a nodule-derived Pseudomonas.
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BibTeX
@article{m2026beyond,
title = {{Beyond contact toxicity: Volatile and systemic nematode suppression by ‘Candidatus Pseudomonas auctus’ JDE115 in soybean}},
author = {Ali M. S. and Mony F. T. Z. and Evans M. and Rideout S. and Haak D. and Eisenback Jonathan D.},
journal = {Journal of Nematology},
year = {2026},
month = oct,
doi = {10.2478/jofnem-2026-0030},
url = {https://doi.org/10.2478/jofnem-2026-0030},
note = {CC BY},
}
RIS
TY - JOUR
TI - Beyond contact toxicity: Volatile and systemic nematode suppression by ‘Candidatus Pseudomonas auctus’ JDE115 in soybean
AU - Ali M. S.
AU - Mony F. T. Z.
AU - Evans M.
AU - Rideout S.
AU - Haak D.
AU - Eisenback Jonathan D.
PY - 2026
DA - 2026/10/26
JO - Journal of Nematology
DO - 10.2478/jofnem-2026-0030
UR - https://doi.org/10.2478/jofnem-2026-0030
AB - Plant-parasitic nematodes such as soybean cyst nematodes (SCNs) (Heterodera glycines) and root-knot nematodes (Meloidogyne spp.) pose a significant threat to global soybean productivity. This study evaluated the multimodal biocontrol potential of ‘Candidatus Pseudomonas auctus’ JDE115, a soybean nodule-derived bacterium known for its plant growth-promoting properties. Greenhouse-based pot and split-root assays showed that JDE115 not only significantly improved soybean growth and nodulation but also suppressed SCN reproduction by over 90% locally and 85% systemically, indicating both direct antagonism and possibly induced systemic resistance. Volatile profiling using solid-phase microextraction gas chromatography–mass spectrometry identified dimethyl disulfide and 1-undecene as distinctive volatile organic compounds produced by JDE115. Bioassays with free-living nematodes demonstrated that 1-undecene elicits strong avoidance behavior and causes rapid mortality in nematodes in the absence of direct contact. Furthermore, a colorimetric picrate assay confirmed substantial hydrogen cyanide production by the bacterium. Additional tests revealed that JDE115 inhibits egg hatching and causes juvenile mortality through a combination of chemical toxicity and enzymatic degradation. Collectively, these findings establish JDE115 as a multifunctional plant growth-promoting rhizobacterium with potential nematicidal activity and broad biocontrol potential, underscoring its value as a next-generation microbial tool for integrated nematode management in soybean cultivation. To our knowledge, this is the first report demonstrating combined volatile-mediated and systemic suppression of SCN by a nodule-derived Pseudomonas.
SN - 2640-396X
SN - 0022-300X
ER -