| Sumario: | The experiment was carried out from February 2020 to November 2021 in two Clementine mandarin orchards from Valencian Community (Spain). The orchards were located in Borriol (40°00'45.5"N 0°05'56.3"W 110 m. a.s.l) and Moncófar (39°48'12.1"N 0°09'58.7"W 15 m. a.s.l) and were 1.4 and 1.1 ha, respectively. Both orchards were selected because they had a medium abundance of D. aberiae. Eight replicated blocks were evenly distributed across the two orchards. Each block was divided into paired 4x4 tree plots, one receiving the “ant-allowed” treatment and the other receiving the “ant-excluded” treatment. In ant-excluded plots, sticky barriers were applied to trunks of trees to prevent ants accessing up to the canopy. To do this, the tree trunk was wrapped with Parafilm® 10-30 cm above ground. The wrapped zone was coated with Tad All-Weather® adhesive. The four central trees of each plot were sampled monthly. From each tree, 40 leaves (ten leaves per cardinal direction) and 20 fruits (five fruit per cardinal direction) were visually inspected, and the number of mealybugs, ants and potential predators were identified and counted. The number of ants crossing (both up and down) an imaginary line surrounding the trunk at 30 cm above ground were counted for two minutes. Ants were identified to species and predators identification varied among groups from order (e.g. Araneae) to species (e.g. Rodolia cardinalis). All observations were made between 9 a.m. and 4 p.m., as ant activity in citrus canopies is stable over this period.
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