EFFECT OF ROOT EXUDATES OF TAGETES SP. ON EGG HATCHING BEHAVIOR OF MELOIDOGYNE INCOGNITA

Abstract

The effect root exudates of pre-planted marigold intercropped with tomato in regulating the hatching behavior of root-knot nematode - Meloidogyne incognita eggs were investigated. Marigold cultivars Tagetes patula, T. minuta, T. erecta, T. erecta (var. Orange), T. erecta (var. Yellow) significantly reduced the numbers of second-stage juveniles (J2s) in subsequent tomato compared to the tomato-tomato control. Four different concentrations (25, 50, 75 and 100 %) of water soluble extract from the selected varieties of Marigold cultivars were filtered and added to the petri dish and infested with the eggs of M. incognita. Data indicate that egg hatching was significantly affected by root exudates of Tagetes sp. however, nematicidal activity was species dependent. Root exudates of T. erecta were lethal to J2 of M. incognita and were inhibitory to the hatch of eggs at the concentration of 75 % or higher.