EFFECT OF Trichoderma harzianum ON TOMATO (Solanum lycopersicum L.) SEED GERMINATION, SEEDLING VIGOUR AND ROOT-KNOT INCIDENCE OF TOMATO FIELDS
Tomato is a major crop of high economic importance cultivated worldwide and yields highly per unit area of land compared with other tropical vegetables. One of the major challenge with production in the tropics is the infestation of root-knot nematodes. Laboratory and field experiments to study the effect of different concentrations as well as different durations of exposure of Trichoderma harzianum (Eco-T) as a seed treatment on the management of root knot nematode and effects on seed germination and seedling performance of UC 82 tomato variety were conducted in the dry season in the Greater Accra region. A Completely Randomised Design (CRD) was used in the laboratory study. It comprised 25 seeds sown per petri-dish replicated four times. The effect of the seeds coated with Trichoderma harzianum (Eco-T) at concentrations of 0 g, 0.2 g, 0.25 g, 0.3 g, 0.35 g, and 0.4 g prior to sowing revealed Trichoderma harzianum (Eco-T) at a rate of 0.2 g and 0.4 g/10 g of seeds produced the best germination percentage, root and shoot lengths of seedlings and seedling vigour index. A follow up study to evaluate the different durations of Eco-T at 30 min, 1hr, 3 hrs, 6 hrs, 8 hrs, 24 hrs, 30 hrs, 48 hrs, and no coating using the recommended rate (0.2 g/10g seeds) showed coatings for 30 minutes and 3 hrs, giving the best seed germination, root and shoot lengths, and seedling vigour index respectively. A combination of concentration (0 g, 0.2 g, and 0.4 g/10 g of seeds) and duration of exposure (30 min and 3 hrs of application) resulted in optimum germination, root and shoot lengths as well as seedling vigour index for 0.4 g/10 g of seeds at 30 minutes exposure. A field study arranged in Randomized Complete Block Design (RCBD) with 4 replications was employed to study influence of Trichoderma harzianum (Eco-T) as a seed treatment on root-knot nematodes. Velum (Fluopyram SC 400 G) at a rate of 3.8 mL/7 L of water was used as a reference. Impact of the treatments on seedling emergence, plant growth, incidence of nematode root knots, nematode populations and egg masses as well as yield of UC 82 tomato were recorded. Trichoderma harzianum (Eco-T) treatments were effective in keeping nematode populations and galling low, comparable to the Velum (Fluopyram SC 400 G). Plant growth was significantly influenced by both Trichoderma harzianum treatments and Velum (Fluopyram 400 SC) treatment. Yield however was higher in Velum (Fluopyram SC 400 G) although the differences were not significant compared with Trichoderma harzianum. A partial budget analysis suggested Trichoderma harzianum to be more cost effective compared to Velum (Fluopyram 400 SC).