Evaluation of Trichoderma Harzianum and Solarization for the Management of Fusarium Wilt and Southern Blight Diseases of Tomato

Abstract

The efficacy of Trichoderma harzianum and soil solarization was determined solely and in combination for the management of fusarium wilt and southern blight diseases of tomato. The treatments comprised two concentrations of T. harzianum, (104 and 107 spore/ml), two levels of solarization, (one and two months), and the interaction between solarization and T. harzianum. Formaldehyde, a soil fumigant was the standard check and the control consisted of untreated soil. The causal pathogen of the diseases was separately inoculated at 106 spore/ml into wide surfaced (410mm diameter) plastic pots of 15 liters containing 15kg of soil. Clear transparent polythene of 0.05mm thickness was used to achieve solarization. Local tomato cultivar, Hausa scissors, was the test crop and it was sown in nursery tray on a sterile nutrient-rich soil, irrigated with equal water volume and transplanted after 21 days into the treated soil. The pots were placed in the open field throughout the growing season. The experiment was arranged in a randomized complete block design with three replications for each treatment. Data collected were subjected to statistical analysis and mean separation using Minitab software. The interaction of T. harzianum at 107 spore/ml and two months solarization significantly reduced the incidence and severity index of the two diseases, increased plant growth parameters, yield quality and quantity and enhanced fruit shelf life and may be recommended for the management of fusarium wilt and southern blight diseases of tomatoes than their application as sole management agents.