NEMATICIDAL ACTIVITY OF BARK OF SOME TREE SPECIES AGAINST ROOT KNOT NEMATODE MELOIDOGYNE JAVANICA (Treub) Chitwood

Abstract

Root-knot nematodes (Meloidogyne species) are the most abundant and destructive nematodes around tropical areas of world. Barks of 10 indigenous tree species namely Azadirachta indica, Tamarindus indica, Delbergia sissoo, Eucalyptus sp., Aegle marmelos, Guaiacum officinale, Thespesia populnea, Pithocellobium dulce, Prosopis juliflora and Samanea saman were assessed against root-knot nematodes Meloidogyne javanica (Treub) Chitwood under laboratory and greenhouse conditions. Aqueous extract of bark of Eucalyptus sp. revealed greatest inhibition of hatching of root-knot nematodes juveniles. Similarly, highest mortality (98.4%) of juveniles was observed in Eucalyptus sp. treatment. Soil amendments with barks of different trees greatly enhanced Seed germination, Shoot and root heights and weights in okra. A. indica bark provided maximum growth enhancement in okra plants. Root-knot nematode parasitism in okra decreased with the bark treatments. However, the bark of A. indica was the most effective against root-knot nematode parasitism in okra.