MANAGEMENT OF MELOIDOGYNE-INCOGNITA ON COTTON BY USE OF BOTANICAL AROMATIC-COMPOUNDS

The efficacy of benzaldehyde (benzoic aldehyde), citral (3,7-dimethyl- 2,6-octadienal), furfural (2-furaldehyde), menthol (5-methyl-2-(1-meth lethyl)cyclohexanol), and alpha-terpineol (alpha, alpha, 4-trimethyl-3 -cyclohexene-1-methanol) for management of Meloidogyne incognita was t ested on 'Deltapine 50' cotton (Gassipium hirsutum) in a greenhouse ex periment. Mixing these compounds into a sandy loam soil-sand mixture a t rates ranging from 0.1 to 0.5 ml/kg reduced the number of M. incogni ta juveniles in cotton roots and soil. The number of galls/g root tiss ue was reduced, and the compounds had no adverse effects on cotton gro wth. The percentage of root colonized by vesicular-arbuscular mycorrhi zae (VAM) was decreased with increasing concentrations of compounds. C itral and menthol significantly increased plant height at all rates of application. Benzaldehyde, citral, and furfural were tested in field microplots at rates ranging from 0.18 to 2.14 ml/kg soil. In all exper iments, the compounds were incorporated into the soil approximately 2 weeks prior to planting. Benzaldehyde, citral, and furfural reduced po pulations of M. incognita at all rates without adversely affecting pla nt height or yield. Results indicate that these compounds could have p ractical application in the management of M. incognita on cotton and t heir further evaluation as components in integrated pest management is warranted.