Screening and Identification of Antagonistic Fungi Trichoderma spp. for Inhibition of Important Plant Pathogens

Abstract

Antagonistic fungi Trichoderma spp. were isolated from forest and cultivated soils in the southern region of Thailand. One hundred eighty-three isolates of Trichoderma spp. and Trichoderma-like fungi were obtained from the soil plate technique. All isolates were toested in vitro for inhibition of mycelial growth of Phytophthora palmivora, Rhizoctonia solani and Sclerotium rolfsii. Cultivated soils were a better source of potential antagonistic fungi Trichoderma spp. than forest soils because they harbored inolates of Trichoderma spp. which wee aggressive against three species of plant pathogens. four isolates of Trichoderma spp. and two isolates of gliocladium spp. had a potential as selected biological control agents. These potential fungal antagonists were identifed using Scanning Electron Microscope (SEM) as Trichoderma harzianum (isolate no. 0123), Trichoderma viride (siolates no. 0140), and Gliocaldium virens (isolates no. 0104 and 0138) were- an unidentified species (isolate no. 0015 and no. 0173).