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Fresh leaf samples ofNicotiana plumbaginifolia, Wedelia chinensis, Cassia toraandJatropha curcas,and flowers ofW. chinensis, Catharanthus roseusandCalendula officinaliswere evaluated for their hatching inhibitory and juvenile mortality potential and to ascertain their role as organic amendment for the management of root-knot nematode,Meloidogyne incognitaaffecting Okra (Abelmoschus esculentus). Four concentration levels i.e. S, S/2, S/10 and S/100 of aqueous leaf and flower extracts of test plants were prepared. All the extracts showed varied but significant results over control (Distilled water). The “S” concentration of aqueous flower extracts ofC. officinalisandW. chinensisexhibited 100% mortality after 24?h exposure period. Similarly, larval hatching was completely inhibited by “S” concentration of extracts of all the tested plants exceptC. toraafter five days of exposure period. All the flower extracts andN. plumbaginifolialeaf extract showed complete suppression atS/2 concentration. Increased dilution showed a direct effect on hatching but an inverse effect on mortality. The juvenile mortality increased with increase in exposure period. In pot trial studies, application of all the samples significantly enhanced the plant growth and decreased the host infestation byM. incognitaover control. Among all the treatments, flowers of C. officinalisand leaves ofJatropha curcusproved to be the best. [ABSTRACT FROM AUTHOR]

Nematicidal activities of extracts from plants were assayed againstMeloidogyne incognita in vitro.Leaves of six different plants were collected in and around Aligarh Muslim University Campus. Aqueous extracts of six plants were screened for egg hatchability and nematicidal activity against second stage juveniles ofM. incognitain the plant pathology and nematology laboratory, AMU Aligarh. The nematode egg and juveniles were exposed 12, 24 and 48 h in (S, S/2, S/10, S/100) concentrations of plant extracts. The plant extracts of leaves of six plants species viz.Jatropha pandurifolia,Polyalthia longifolia, Wedelia chinensis,Nerium indicum, Duranta repensandCassia fistulaexhibited highly promising mortality of 99.00–72.00% after 48 h of exposure. Aqueous extracts of leaves ofJ. pandurifolia, P. longifolia, W. chinensiswere recorded to be highly effective for inhibition of egg hatching and increasing juvenile mortality ofM. incognita. There was a gradual decrease in egg hatching and increase in mortality rate of juveniles ofM. incognitawith increase in the concentration of leaf extract and exposure time. [ABSTRACT FROM PUBLISHER]