Evaluation of the Efficacy of Trichoderma spp against the Fungus Fusarium of Wilt Disease of Tomato plants

Abstract

A series of laboratory and shed house experiments was conducted at Environment and National Resource and Desertification Research Institute, department of biopesticides and biofertilizer. Tomato crop are affected by many viral and fungal disease and insect pests, but Fusarium wilt disease is an important one causing significant reductions in yield. The objective of the study was to use the biological control method of Fusarium wilt disease on tomato crop. Two experiments (in vitro and in vivo), was conducted to study the antagonistic effect of Trichoderma .viride and Trichoderma. harzianum and fungicide Stariva (25EC) on the growth of the fungi F. oxysporum. The pathogenic fungus was isolated from infected plant parts. The fungus was identified based on morphological and cultural characters as Fusarium oxysporum f. sp. lycopersici. In the in vitro experiments, three concentrations 25%, 50% and 75% of T.viride and T. harzianum and 50%, 75% and 100% of Stariva were prepared. The assessments of their inhibitory effect against the pathogen were recorded through the fungal growth inhibition percentage. The results showed that all concentration of the T. harzianum and T. viride using dual Petri plate method inhibited the growth of F. oxysporum at the 5th and 6th days after application. Five days after application T. harzianum have high mycelia inhibition percentages 78.57% and 77.14 % at 75% and 50% concentration respectively. The lowest concentration of T. viride (25%) was the superior in inhibiting the fungal mycelia growth (84.28%) which was similar to the highest concentration of Stariva (100%) at the 5th days after application. At the concentrations 50% and 75%, T. viride resulted in an inhibition percent of 78.57% and 80% respectively, 5 days after application. The fungicide Stariva at 100% concentration, 5 days after application were superior in recording a high inhibition percentage of 84.28%. Whereas, the chemical inhibited the mycelia growth by 77.14% and 77.19% at 75% and 50%, concentrations respectively, compared to control. In shade House Experiment the results indicated that the highest percentage increase in branches number was recorded by T. harzianum (28.67%) in 30%concentration which applied 21 day after The highest percentage increase in leaves number (29.16%) were recorded when , T. harzianum 20%+ Stariva, T.harzianum 30%+ T.viride 20% and T.harzianum20%+T.viride.30% were applied 42d.a. the highest percentage increase in height leaves number (20%) were recorded when, T. harzianum 20%+ Stariva, T.harzianum 30%+ T.viride 20% and T.harzianum30%+ Stariva were applied 42d.a.a