Ability of Trichoderma harzianum in carbon fiber and silica nano particles formulation to control Fusarium oxysporum in vitro

Abstract

Basal rot disease caused by Fusarium oxysporum f. sp. cepae is one of the major diseases that cause yield loss on shallot. Utilization of biocontrol agents can be applied as an environmentally safe control method. The antagonistic microorganism that has the potency to control fusarial diseases is Trichoderma harzianum. A carrier is required in preparing a formulation of this antagonistic fungus as a biocontrol delivery system (BDS). Carbon fiber was proven suitable as a carrier of some antagonistic bacteria. A formulation can also be supplemented with plant micronutrient. Addition of silica nano particles (Si NPs.) in the formulation did not reduce the viability of the antagonistic bacteria. An experiment was carried out to determine the ability of T. harzianum in the formulation with carbon fiber and Si NPs. to suppress the in-vitro growth of F. oxysporum. The experiment was arranged in the completely randomized design with 5 treatments and 5 replications. The treatments were challenging F. oxysporum by T. harzianum in different composition of formulation on potato dextrose agar. The compositions consisted of T. harzianum + 0.5% Si NPs., T. harzianum + 1% Si NPs., T. harzianum + 0.5% Si NPs. + 5% carbon fiber, T. harzianum + 1% Si NPs. + 5% carbon fiber, and T. harzianum only (control). The results showed that each treatment with T. harzianum in the formulation of carbon fiber + various concentrations of Si NPs. was able to suppress the in vitro growth of F. oxysporum by 58.39-60.92%. The BDS with carbon fiber and Si Nps. did not significantly reduced the ability of T. harzianum to antagonize F. oxysporum. The control treatment of single T. harzianum caused the highest suppression on the growth of F. oxysporum, up to 60.93%..