Economic threshold for Tetranychus urticae (Acari: Tetranychidae) in clementine mandarins Citrus clementina

摘要: Tetranychus urticae is a key pest of citrus in Spain, especially clementine mandarin trees. The effects this mite on fruit production were assessed 24 trees for three consecutive years. Trees visited weekly and spider phytoseiid populations leaf flush patterns estimated. At the end season, mandarins harvested, weighed, damage (scarring fruit) characterized. Negative relationships between density yield (kg/tree) (% scarred rind) found. multivariate regressions highlighted role mites patterns, which negatively related to damage. shortest sampling period that satisfactorily predicted at harvest, extended from August mid-October. For IPM purposes, an action threshold 31.1 m−2 symptomatic was Taking into account dynamics, economic ranged 10 15 leaf. When exceeded growers would have 1-week window apply control technologies against T. their choice.