ARS | Publication request: PLANT-DERIVED COMPOUNDS ACTIVE AGAINST MELOIDOGYNE INCOGNITA

Submitted to: Journal of Nematology
Publication Type: Abstract
Publication Acceptance Date: March 30, 2006
Publication Date: June 1, 2006
Citation: Meyer, S.L., Zasada, I.A., Roberts, D.P., Vinyard, B.T., Lakshman, D.K., Lee, J.K., Chitwood, D.J., Carta, L.K. 2006. Plant-derived compounds active against meloidogyne incognita [abstract]. Journal of Nematology. 38:283.

Technical Abstract: Products from two plant genera, Plantago and Eugenia, were tested for effects on the root-knot nematode Meloidogyne incognita. Extracts from P. lanceolata and P. rugelii were also evaluated for toxicity to the plant-pathogenic fungi Fusarium oxysporum f. sp. gladioli, Phytophthora capsici, Pythium ultimum, and Rhizoctonia solani, and to the beneficial microbes Enterobacter cloacae, Pseudomonas fluorescens and Trichoderma virens. Plantago extracts were prepared in methanol and in water from dried shoots and roots of field-collected plants. Clove oil from E. caryophyllata was purchased from Sigma Chemical Company (St. Louis, MO). All Plantago and Eugenia extracts were lethal to second-stage juveniles (J2) of M. incognita, and also inhibited egg hatch. J2 were more sensitive than eggs to lower concentrations of the Plantago extracts (25% and 50%), but effects on the two life stages were similar at 75% and 100% concentrations. J2 and egg hatch activity decreased by 65%-72% at the 75% concentration. The Plantago extracts were not toxic to the tested bacteria and fungi. Direct exposure to 0.2% clove oil resulted in 100% loss of J2 viability, and inhibited egg hatch 97.5%. Clove oil did not exhibit as pronounced a difference in toxicity to eggs and J2 as was observed with Plantago extracts.