논문 상세보기
Dispersal of Tetranychus urticae and its predatory mite on connected strawberry leaves
The study was conducted to investigate dispersal of T.urticae and its predatory mite on connected strawberry leaves. The experiments were run on laboratory conditions, 24±1℃, 50-65% RH, and a photoperiod of 16:8 (L:D). The excised leaf disk (diameter 3cm) of two strawberry varieties- Maehyang, Seolhyang- were placed upside down on a water-saturated cotton pad in an aluminum pan (width x length 17.4 x 21.5cm). Twenty leaf disks were placed on each experimental set and the disks (width x length 4 x 5 ca) were connected with each other for dispersing of T. urticae and its predatory mite. There were six different experiment sets - two strawberry varieties and three treatments (no predatory mite, releasing Neoseiulus californicus, and releasing Phytoseiulus persimilis). The experiment sets were covered with plastic cage to protect from invading other insects and mites. The investigation was conducted by examining two or three times per week and all life stages of T. urticae and predatory mite were reported until all leaves were occupied by mites. Repeated-measures data were analyzed by MANOVA. The average number of T.urticae per cm2 was no significant difference between two strawberry varieties in no predatory mite system (F=0.65, p>0.4195). Although the external structure of two strawberry varieties is very similar the dispersal rate of T. urticae was different between two strawberry varieties in all experiment sets. However, the number of T. urticae per cm2 was no significant different (df=1, F=1.28, p>0.2628). Within the same strawberry variety T.urticae populations among experiment sets were significant different (df=2, F=14.95, p<0.0001 Seolhyang, df=2, F=15.03, p<0.0001 Maehyang).
