Sampling Arthropod Pests in Citrus
Citrus is grown worldwide in tropical and subtropical regions, with both humid and relatively arid climates. The parasitic fungus Hirsutella thompsonii Fisher is an effective natural enemy of the citrus rust mite, and treatment thresholds can be raised based upon the number of infected mites observed. Despite the low tolerances for cosmetic damage by most citrus pests, control by natural enemies has been economically effective in many cases. Although the density of predaceous mites relative to that of thrips necessary to provide economically effective thrips suppression is not yet known, a number of pest control advisors double the treatment threshold for citrus thrips if predaceous mites are present at a density ≤ 0.2 predaceous mites per leaf. Nevertheless, because yellow traps are used to monitor citrus thrips and citrus psylla, yellow pheromone traps may permit the monitoring of several pests and some of their natural enemies simultaneously.