Aliphatic ketones from Ruta chalepensis (Rutaceae) induce paralysis on root knot nematodes.

Department of Pharmaceutical Chemistry and Technology, University of Cagliari, Cagliari, Italy.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 06/2011; 59(13):7098-103. DOI: 10.1021/jf2013474
Source: PubMed

ABSTRACT This paper reports on the use of Ruta chalepensis L. extracts as a potential nematicide against root knot nematodes Meloidogyne incognita and Meloidogyne javanica . The essential oil (REO) and methanol extract (RME) of R. chalepensis were tested against second-stage juveniles, with REO inducing paralysis in both species (EC(50/1d) = 77.5 and 107.3 mg/L) and RME being selective for M. incognita (EC(50/1d) = 1001 mg/L). Chemical characterization of extracts was done by means of GC-MS and LC-MS, revealing mainly aliphatic ketones and coumarins, respectively. The first-ranking volatile nematicidal component in terms of individual activity against both species was 2-undecanone (EC(50) = 20.6 and 22.5 mg/L for M. incognita and M. javanica, respectively). This fact together with its high concentration in the most active extract found in this study, namely, REO (2926 mg/kg), categorizes 2-undecanone among the nematicidal principles of R. chalepensis. On the contrary, coumarins rutin and 8-methoxypsoralen were not found to be nematicidal at concentrations of ≤500 mg/L. Interestingly, M. incognita was found more sensitive than M. javanica.

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