Field screening of fungicides for effectiveness in pine needle rust control

Abstract

We evaluated the effectiveness of four fungicides for the control of pine needle rust caused by Coleosporium phellodendri in Japanese black pine and Japanese red pine seedlings in fields in Kagawa and Nagano, Japan. The seedlings were planted in nurseries close to amur corktrees (Phellodendron amurense) naturally infected with Co. phellodendri. Among the fungicides used, manzeb WP was consistently the most effective, offering 98.2-100% protection. Although the other three fungicides exhibited low to high effectiveness, depending on the experiment, hexaconazole FL was the second-most protective (54.0-90.9%), followed by thiophanate-methyl WP (43.5-49.1%).