Abstract: The potentiality of different plant extracts like bark of Eucalyptus lanceolotus and Terminalia arjuna, tubers of Cyperus rotundus, leaves of Withania somnifera, Azadirachta indica, Datura stramonium, Acacia arabica, Cymbopogon flexuosus and Parthenium hysterophorus, cloves of Allium sativum, bulb of Allium cepa, fruits of Emblica officinalis and rhizome of Zingiber officinale as inducers were assessed on physiological and biochemical activities in tomato against fusarim wilt caused by Fusarium oxysporum f. sp. lycopersici and the results showed that pre-application of inducers provided protection to the tomato plant and reduced the disease intensity. The minimum disease intensity (8.93%) was reported from garlic extract treated plant whereas, in case of control-I it was 96.12%. Treatment with plant extracts as inducers prior to challenge inoculation sensitized the seedlings to produce increased levels of soluble protein. The maximum increase in protein content was found in garlic extract treated seedlings (32.62 mg g-1) after 15 days of pathogen inoculation. A high content of phenols which are indicators of first stage of defence mechanism, was also recorded in treated leaves with maximum in garlic extract treatment representing 2.28 mg g-1 of fresh leaves against 1.52 mg g-1 of fresh leaves in control-II after 15 days of pathogen inoculation. The soluble protein content (r = -0.5995) and total phenol content (r = -0.5313) both showed a negative correlation with disease incidence. Apart from inducing effect in plant defences, plant extracts have also some direct effect on growth and development of the pathogen. Protein profiling by SDS-PAGE revealed that one new protein is synthesized due to effect of inducers that might be responsible for disease.