COLONIZATION OF TOMATO ROOTS WITH ARBUSCULAR MYCORRHIZAL FUNGI CHANGES OF ANTIOXIDATIVE ACTIVITY AND IMPROVES TOLERANCE TO Verticillium dahliae

The present study aims to assess the effect of autochthonous mycorrhizal fungi “Rhizolive consortium” on Verticillium wilt of tomato plants (Lycoperscum esculentum Mill.) and induction of antioxidant enzymes in response to Verticillium dahliae inoculation. 15 days old tomato plants were inoculated first with Rhizolive consortium for two months then infected with V. dahliae for three months. Our results showed that mycorrhization frequency of tomato root system was slightly affected in the presence of V. dahliae, while in the presence of Rhizolive consortium, mycorrhizal intensity was reduced by about 48%. The growth and yield of mycorrhizal plants were significantly improved compared to the control plants. Moreover, AMF reduced symptoms development as compared to infected tomatoes only by V. dahliae. The leaf alteration index of tomato plants was reduced in mycorrhiza-infected tomato plants by 58%. Mycorrhizal tomato pants significantly reduced Malonyldialdehyde accumulation in the presence of Verticillium dahliae by 20% and 38% in the leaves and roots tissue, respectively. In contrast, inoculated tomato plants with Rhizolive consortium alone significantly increased (p = .05) catalase, superoxide dismutase, peroxidase, polyphenoloxidase activities in the roots compared to other treatments. Subsequently, antioxidant enzyme activities were induced slightly in response to V. dahliae inoculation. These results showed clearly that AMF protect tomato plants and contributes to the suppression of V. dahliae.