- Author: Elizabeth E Grafton-Cardwell
As of APRIL 20, 2018 Delegate (spinetoram) has been removed from the list of approved insecticides for the treatment of citrus just prior to harvest for the purpose of disinfesting citrus prior to moving citrus-filled bins between quarantine zones in California. The regulations for 'spray and move' can be found on the CDFA information for citrus growers/grove managers web page and the table from that document is shown below. The reason for removing Delegate, is that it shows significantly less control of psyllids than the other treatments on the list. It is critical to achieve high kill of psyllids to ensure fruit is disinfested, so that psyllids, and potentially HLB, are not moved around the state. The alternative to 'spray and move' is field cleaning (brushing or washing fruit) and removing leaves and stems from the fruit and bins. The eggs and nymphs attach themselves to leaves and stems and the adults can ride on fruit.
In recognition of the issues related to treating citrus just prior to harvest, research is being conducted by the USDA and University of California to develop fogging and fumigant post harvest systems to disinfest fruit that will ultimately replace 'spray and move' treatments.