Nematicidal Screening of Aqueous Extracts from Plants of the Yucatan Peninsula and Ecotoxicity.

Active metabolites from plants are considered safer than synthetic chemicals for the control of plant-parasitic nematodes of the genus Meloidogyne . In the present work, 75 aqueous extracts (AEs) from different vegetative parts of 34 native plant species of the Yucatan Peninsula were evaluated against second-stage juveniles (J2s) of Meloidogyne incognita and M. javanica in microdilution assays. The highest mortality (M) against both Meloidogyne species was produced by the foliar AE from Alseis yucatanensis (M ≥ 94%) and Helicteres baruensis (M ≥ 77%) at 3% w / v after 72 h. Other active AEs at 3% were from the leaves of Croton itzaeus and stems of H. baruensis (M: 87-90%) on M. javanica and the stems of Annona primigenia and the leaves of Morella cerifera on M. incognita (M: 92-97%). The AEs from A. yucatanensis had the lowest LD 50 against M. incognita (0.36% w / v ), and against M. javanica (3.80% w / v ). In an acute ecotoxicity assay of the most promising AEs using non-target earthworms ( Eisenia fetida ), the AE of A. yucatanensis had slight acute toxicity (LD 50 : 2.80% w / v ), and the rest of the most active AEs were not ecotoxic. These tropical plants are potential candidates for further studies as biorational agents for controlling Meloidogyne species.