EFFICACY OF GROWTH MEDIUM (MURASHIGE&SKOOG) SUPPLEMENTED WITH CERTAIN ESSENTIAL OILS ON TOMATO ROOTS SUITABILITY TO Meloidogyne incognita INFECTION UNDER GREENHOUSE CONDITIONS.

Abstract

The influence of six essential oils i.e. garlic, sesame, neem, castor, chamomile, and linseed added to aseptic culture (MS medium) used for growth of tomato seedlings cv Strain-B before transplanting in pots with sterilized sandy loam soil on Meloidogyne incognita infection was studied under greenhouse conditions 30±5°C. Results indicated that all of the tested essential oils introduced into growth media protected and improved tomato plant growth of either the infected or uninfected with nematodes to a certain extent. Among all tested materials, castor oil gave the highest increment in fresh weight of the whole plant either infected or uninfected with values of 135.42% and 217.59%, respectively. The same trend was observed with castor oil in respect to increasing shoot dry weight of the healthy tomato plants (37.14%) whereas recorded the second to linseed oil treatment with the infected plants with values of 32.56% and 35.2%, respectively. Moreover, sesame oil application achieved the second values to castor oil treatment in increase percentage of both fresh weight of whole plant (132%) as well as shoot dry weight (29.24%), respectively. The highest reduction percentage in nematode population was obtained with castor oil treatment which amounted to 93.53% followed by linseed oil application with value of 92.71%. Among all tested essential oils, sesame oil significantly decreased number of galls on tomato roots with reduction percentage of 90%, followed by those treated with either chamomile or linseed oils with value of 87.5% each. M. incognita did not produce egg-masses on plants treated with all of the tested materials and considered as highly resistant due to egg-masses indices (zero each) whereas those received linseed oil as very resistant with egg-masses index value of 3 and reduction percentage value of 97.4%.