ANTAGONISTIC POTENTIAL OF Trichoderma harzianum AGAINST F. oxysporum f. sp. lycopersici ISOLATES CAUSING FUSARIUM WILT DISEASE OF TOMATO (Solanum lycopersicum L.)

Abstract

Antagonistic effect of T. harzianum was carried out on F. oxysporum f. sp. lycopersici. isolates of tomato variety (UC 82B) in a screen house located at the Teaching and Research Farm of Federal University of Agriculture, Makurdi during 2015 cropping season to determine the ability of the antagonistic in controlling Fusarium wilt diseases of tomato. The F. oxysporum isolates tested were coded as: FoAs1, FoAs2, FoAg, FoNb, FoSb, FoAm, FoAk, FoOr, FoAd and FoUAM together with an uninoculated control. The experiment was a 2 x 11 factorial laid out in Completely Randomized Design (CRD) and replicated three times. T. harzianum was introduced at three different times (Two days before, same time and two days after the inoculation of F. oxysporum). In vitro tests results revealed antagonistic effects of T. harzianum on F. oxysporum isolates. Growth inhibition was significantly higher (P≤0.05) when T. harzianum was introduced two days before inoculation of F. oxysporum. Interaction shows that T. harzianum introduced two days before inoculation of F. oxysporum gave better inhibition of all the Fusarium isolates tested except isolates FoAd and FoAg compared with when the antagonist was introduced at the same time and when it was introduced two days after inoculation of F. oxysporum. Also, T. harzianum (P≤0.05) totally inhibited the growth of isolates FoAg, FoAs1, FoNb, FoOr and FoUAM but not those of FoAd, FoAk, FoAm, FoAs2 and FoSb. It is therefore recommended that T. harzianum be used in the management of fusarium wilt disease of tomato