| This research was carried out to evaluate the effectively of five essential plant oils ( Black seeds oil , Cardamom oil , Aniseed oil , Aloevera oil and Clove tree oil ) in the inhibition of growth of four types from fungi (Pythium aphanidermatum , Rhizoctonia solani , Fusarium moniliforme and Fusarium poae ) at 250 , 500 , 1000 part per billion In Vitro . Bioassay test results showed the significant differences and the superiority Clove tree oil in inhibiting the growth of four fungi and as it was ( 0.0 % ,100 % , 100 % ) , ( 37.22 % , 88.07 % , 100 % ) , ( 11.11% , 48.33 % , 71.11 % ) and ( 5.55 % , 100 % , 100 % ) respectively .Meanwhile , the rest of essential plant oils showed different activity on growth of pathogenic. |