Pathogenicity of Fusarium solani associated with a bark beetle, Scolytogenes birosimensis, to Pittosporum tobira

Abstract

Pittosporum tobira seedlings were inoculated with Fusarium solani isolated from Scolytogenes birosimensis, a bark beetle that infects P. tobira. The fungus produced necrotic lesions in the phloem and a discolored zone in the sapwood. Seedlings inoculated with the fungus and grown under weak light conditions were killed within 12–30 days after inoculation. Isolates from both S. birosimensis, which has caused P. tobira decline in Aichi and Fukuoka prefectures, and from the beetle under endemic conditions in Ibaraki Prefecture were both pathogenic to P. tobira.