POSTERS: Biological control
Characterization of Trichoderma sp. isolates for use in biological control of plant pathogens
Beatriz de Toledo Franceschi - São Paulo State University "Júlio de Mesquita Filho". Cristiane De Pieri- São Paulo State University "Júlio de Mesquita Filho", Edson Furtado- Univ of Sao Paulo State (UNESP)
Trichoderma sp. is a fungus found in the soil and works as a biofungicide due their parasitism, antibiosis, and competition. Some species are resistance inductors of plant diseases. The objective of this study was to evaluate the mycelial growth and sporulation of 22 isolates of Trichoderma sp. collected from regions in Brazil to be used as biological control of different pathogens. Each isolate grew under a 12-hour photoperiod at 25°C. The mycelial growth was also compared in PDA and oatmeal-agar media, and the colony diameter was measured daily for 3 days. Sporulation was measured with a hemocytometer by counting conidia produced after five days. Mycelial growth was faster in PDA than oatmeal-agar media. Five isolates had significant differences on mycelial growth (A4, A5, A6, A8 and A20), but A5 showed the highest growth. There were also significant differences among isolates for conidia production, and A5 presented the highest value. Isolate A3 presented the lowest mycelial growth and sporulation. Therefore, the A5 Trichoderma sp. isolate could be a potential bio control agent against plant pathogens because of its rapid growth and conidia production in culture.