Nematicidal activity of the hydrolate byproduct from the semi industrial vapor pressure extraction of domesticated Artemisia absinthium against Meloidogyne javanica

The objective of this study was the characterization of nematicidal activity and valorization of hydrolate obtained as a byproduct of the semi industrial vapor-pressure essential oil extraction of a domesticated Artemisia absinthium population (Teruel, Spain), in comparison with a population (Sierra Nevada, Spain)undergoing the domestication process. Hydrolates from three crops of these two populations showed strong in vitro nematicidal effects against the root knot nematode Meloidogyne javanica and similar chemical profiles. The hydrolate of the A. absinthium population from Teruel strongly suppressed nematode egg hatching (>95 percent)after 5 days of incubation. In vivo tests on tomato seedlings showed a significant reduction in the of root penetration rate of M. javanica J2 treated with a hydrolate sublethal concentration (33 percent). In pot experiments, the hydrolate of A. absinthium tested on tomato plants significantly affected the nematode population, the infection frequency and the reproduction rate. The extraction of the organic fraction of the hydrolate gave a nematicidal extract and an inactive aqueous residue. The chemical profile of the active organic extract showed the presence of (5Z)-2,6-dimethylocta-5,7-diene-2,3-diol, previously described in the hydrodistilled essential oil of this A. absinthium population, among other compounds. This study demonstrates that the organic fraction of the A. absinthium hydrolate is a potential root-nematode control agent. Therefore, the hydrolate byproduct of the semi industrial vapor-pressure essential oil extraction could be a source of new nematicidal products.