The objective of this study was to evaluate the effective inoculation position of Neoseiulus californicus for control of Tetranychus urticae on apple branch. This study was conducted under green house conditions. N. californicus was inoculated at different position (Top, Middle and Bottom) of apple branch with a 20:1 ratio (T. urticae:N. californicus). Overall, N. californicus significantly reduced T. urticae numbers in the treatment branches than in the control branch. At 10th day, the T. urticae population was most significantly reduced in the treatment ‘Top’ in which N. californicus were inoculated on the leaf positioned in the top of a branch than in other treatments. At 20th day, most of T. urticae were exterminated in all treatment branches. The daily movement of N. californicus and T. urticae,and their coexistence on apple branch was monitored. Adult N. californicus disappeared from the branch as soon as T. urticae were exterminated in the treatment branches. The result indicates that N. californicus disperse downwards more than upwards in the tree, and the most effective inoculation position for N. californicus for control of T. urticae is the leaves positioned in the top of a branch.

• TaeGyun Kim(Entomology Program, Department of Agricultural Biotechnology, Seoul National University)
• YongJun Kwon(Entomology Program, Department of Agricultural Biotechnology, Seoul National University)
• JeongJoon Ahn(Entomology Program, Department of Agricultural Biotechnology, Seoul National University)
• Joon-Ho Lee(Entomology Program, Department of Agricultural Biotechnology, Seoul National University)