Isolation and Selection of some Antagonizing Fungal Strains of Trichoderma And Chaetonium that can Inhibit the Growth of Pathogenic Fungi on Orange Trees

Decline disease has been discovered for a long time but infection is more extensively increasing. It is difficult to detect because the disease is originated from roots. Among the causes, soil fungi have been widely determined. Using fungicides is not an effective way to control the disease. In this case, biocontrol with suitable microbial strains is a potential approach. This study aims to investigate in vitro the possibility of using Trichoderma and Chaetonium to control the causing fungi. Two Chaetonium strains and 1 Trichoderma asperellum strain were isolated from diseased-root samples. Six strains of Trichoderma (isolated strains T1, T2, T3, T4, T5, T6) and three strains of Chaetonium (isolated strains C1, C2, C3) showed a reasonably antagonistic ability to Phytophthora, Fusarium, Rhizoctonia. Base on the PCR identification method, 6 strains of Trichoderma was isolated belonging to Trichoderma asperellum species, and 3 strains of Chaetonium belonging to 2 species Chaetomium globosum and Chaetomium cichlids.