Abstract
Antagonistic actions of Trichoderma spp. to Rosellinia necatrix and Helicobasidium mompa on PDA medium were determined for 16 isolates obtained from various districts of Japan.
1. All of 16 isolates of Trichoderma spp. tested showed antagonistic action of Rosellinia necatrix, but among them there was a difference in antagonistic action to the causal fungus.
2. Most of isolates of Trichoderma spp. showed antagonistic action to Helicobasidium mompa, but a few of them did not show any antagonistic action of Helicobasidium mompa.
3. One isolate of Trichoderma spp. (T-13) showed the most active antagonistic action to both Rosellinia necatrix and Helicobasidium mompa.
4. Generally speaking, antagonistic actions of Trichoderma isolates were more active to Rosellinia necatrix than to Helicobasidium mompa.
