Possibility of simultaneous control of pine wilt disease and Thecodiplosis japonensis and or Matsucoccus thunbergianae on black pine (Pinus thunbergii) by abamectin and emamectin benzoate

Abamectin 1.8% EC and emamectin benzoate 2.15% were evaluated the simultaneous control effect of both insect pests on black pine (Pinus thunbergii) against Thecodiplosis japonensis and Matsucoccus thunbergianae. Abamectin 1.8% EC was highly effective against T. japonensis and M thunbergianae, however, emamectin benzoate was highly effective against only M. thunbergianae when abamectin and emamectin benzoate were applied through trunk injection against T. japonensis and M thunbergianae at the rate of 1 ml per cm in diameter of breast height. The rate of gall formation of T. japonensis was 0% at the applied year, but 85% at the following year. However, the rate of gall formation was over 90% at the treatment of emamectin benzoate showing no difference compared with control. Abamectin 1.8% EC and emamectin benzoate 2.15% showed high control efficacy representing 89.1% and 91.4% against M. thunbergiana, respectively.