MANAGEMENT OF Meloidogyne incognita DAMAGING LETTUCE: POTENTIAL OF CHROMATOGRAPHIC FRACTIONS AND EXTRACTS FROM Lawsonia Inermis

Abstract

Plant parasitic nematodes (PPNs) are acknowledged as a paramount factor which limits the production of staple crops and vegetables. Preferred standard control method had been the use of synthetic nematicides. However, owing to the undesirable consequences of the residual effect of nematicides in the environment, the need for alternative approaches becomes pertinent and this has prompted investigation into the nematicidal potential of extracts from Lawsonia inermis for practicable application on lettuce plants infected with Meloidogyne incognita in field experiments. The leaves of L. inermis were collected and divided into four parts for separate extraction and these were compared with the standard nematicide carbofuran individually. The essential oil (EO) was significantly more potent than the other extracts from L. inermis. There was no significant difference between plants treated with carbofuran and EO. The fractions were significantly better than crude methanol and ethanol extracts of L. inermis. Reproduction of M. incognita on lettuce plant roots was considerably reduced by utilization of L. inermis extracts. Notably higher vegetative growth was observed in treated lettuce plants. The IR, 1 H-NMR and 13 C-NMR spectral data analysis confirmed the presence of sesquiterpenes in the chromatographic fraction. The GC-MS profile indicated phytol as the major constituent of the EO. The results obtained from this study indicates that extracts from L. inermis could be a viable option in the management of M. incognita damaging lettuce in dependable vegetable production.