Observations on the Use of a Predator to Control Red Spider Mite on Commercial Cucumber Nurseries

SUMMARY Observations on three commercial nurseries have shown that the control of Tetranychus urticae Koch on cucumbers by means of the predator Phytoseiulus riegeli Dosse is uncertain when the predator is introduced after natural infestations develop. Artificial and early establishment of predator and prey is required to give predictable results. The presence of other pests and diseases and the need for control measures also affects the interaction between the red spider mite and its predator.