To clarify the control effect of chemical injection in Fagineura crenativora, dinotefuran with high penetration and migration in plants was injected into trunks of young beech trees growing in Atsugi, Kanagawa Prefecture and Shiojiri, Nagano Prefecture before bud break, and insect mortality was evaluated. Eggs oviposited on leaves mostly died with blackening. In addition, all of the first instar larvae hatched from some eggs died, although oviposition of eggs by female adults was not prevented. Among third and fourth instar larvae reared for 3 days in growth chambers with leaves of chemically injected trees, all of the third instar larvae died, fourth instar larvae mostly died or became paralyzed, and some larvae reached the last instar without feeding. No visible injury such as leaf discoloration, closure inhibition of injection holes, or extreme expansion of wood discoloration was observed. The method was concluded to offer high control of Fagineura crenativora and appeared applicable to mature local trees.
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