碩士 國立中興大學 土壤環境科學系所 104 Tomato is one of the most important vegetable crops in the world. However, Fusarium oxysporum f. sp. lycopersici, the causal agent of Fusarium wilt, causes severe economic losses in commercial tomato production. When tomato plants show typical symptoms of Fusarium wilt, it is difficult to control the disease. This study aimed to evaluate the possibility of using Trichoderma sp. as a biocontrol agent to control Fusarium wilt and to determine the effect of tomato seedlings inoculated with the biocontrol agent on nutrient uptake. Trichoderma species were isolated from field soils and commercial composts and identified using morphological characteristics and phylogenetic analyses. Among the 56 Trichoderma isolates collected, isolate CHF 78 showed a considerably antagonistic activity against F. oxysporum f. sp. lycopersici. The physiological characteristics of CHF 78 were further analyzed, and various carrier materials were used to induce the sporulation of the isolate. Moreover, tomato seed