A Study of the Changes in Total Phenol Content in Olive Cultivars During the Interaction between Verticillium Wilt Verticillium dahliae and Root-knot Nematode Meloidogyne javanica

One-year-old seedlings of olive cultivars, Zard, Roghani, Koroneiki and Manzanilla, were transplanted to different sets of pots each pot containing 2000g of sterilized sandy loam soil. The experiment was conducted in a completely randomized design of 32 treatments, each in five replications. Treatments were comprised of: control, mere nematode, mere fungus, and fungus+nematode. Pots were inoculated with (0, 2000, 3000, 4000) J2 of nematode and/or a number of 10 microsclerotia per gram of soil in accordance with the treatments. Quantitative changes in phenolic compounds were studied 1,10,20 and 30 days following inoculation. Ten days past inoculation, the phenolic compounds in different treatments (as compared with control) were increased, but it was only in Koroneiki cultivar that did the fungus+nematode (4000 J2) treatment show a significant difference against control at 5% level (p?0/05). It was in the twenty and thirty days past inoculation treatments and in other cultivars (Roghani, Zard and Manzanilla), that the phenolic compounds in fungus+nematode treatment of 4000 J2 showed a significant difference (at 5% level) as compared with control. Phenolic compound's content (as compared with mere nematode and fungus alone treatments) was increased in the host plants and for the fungus+nematode treatments (p?0/05). Maximum and minimum total phenol content in olive roots in their and leaves were respectively recorded for cv. Koroneiki, Roghani, Zard and Manzanilla.