Suppression of the interaction damage of Meloidogyne incognita and Fusarium oxysporum f. sp. lycopersici to tomato plants by some plant oils

In vitro effect of four plant oils namely roquette, onion, eucalyptus and aloe applied at 25, 50 and 100 % on egg hatching of Meloidogvne incognita and on the mycelium growth of Fusarium oxysporum f. sp. Lycopersici was investigated. Tomato root dip technique was also used to study the suppression of damage produced by the interaction between two organisms, Data showed that all the tested plant oils at selected concentrations caused significant reduction on the numbers of hatched juvenile nematodes with dose dependent manner. The highest reduction was obtained by roquette oil followed by onion, eucalyptus and then aloe oils. Moreover, the results showed that there were significant differences between the various plant oils corresponding to their in vilro inhibitory effect on the mycelial growth of F. oxysporum f. sp. lycopersici comparing to control value. The maximum percentage of inhibition was recorded by onion oil (71.8 %) followed by roquet-te (67.7 %), eucalyptus (60.6 %) and then aloe oils (46.2 %). All the tested plant oils reduced both the interaction damagc produced by the interaction of M. incognita and F oxysporum f. sp. lycopcrsici. The highest reduction was obtained with onion followed by eucalyptus, roquctte and aloe, whereas roquette was found the most potent oil to reduce the number of nematode galls followed by onion, eucalyptus and aloe. It could be concluded that some plant oils such as roquette, onion and eucalyptus can be used in tomato plants as protectant from the infection with fungus and/or nematode under greenhouse conditions instead of using the traditional pesticides.