Effet inhibiteur in vitro et in vivo du Trichoderma harzianum sur Fusarium oxysporum f. sp. Radicis-lycopersici

In vitro and in vivo antagonistic effect of Trichoderma harzianum against Fusarium oxysporum f. sp. radicis-lycopersici. Tests of direct confrontation, on PDA medium or remote confrontation, between Fusarium oxysporum f. sp. radicislycopersici and Trichoderma harzianum, revealed that the latest has inhibited mycelial growth of the pathogen by more than 65% compared to the control and this after an incubation period of about four days at 25°C. Moreover, beyond this period and after six days, T. harzianum invades and also sporulates on F. oxysporum f. sp. radicis-lycopersici colonies revealing its high myco-parasitism. Some interesting results have also been obtained in vivo: indeed, transplantation of tomato seedlings in a mixture of perlite inoculated by F. oxysporum f. sp. radicis-lycopersici and T. harzianum reduced Fusarium crown and root rot incidence compared to seedlings planted in perlite only inoculated by the pathogen. Even better, seedlings planted in perlite containing the pathogen and the studied antagonist present a better vegetative growth and a vigorous root system compared to those of the healthy control (not inoculated and untreated).