Persistence and infectivity of Isaria fumosorosea blastospores sprayed on citrus seedlings in the field for managing the Asian citrus psyllid, Diaphorina citri

This study was designed to test the persistence of Isaria fumosorosea (PFR 97™) as a bioinsecticide on citrus seedlings under field conditions in Fort Pierce, Florida. Leaf wash and Asian citrus psyllid mortality assays were used to quantify the spore viability and infectivity of PFR 97™) at 0, 7, 14, 21, 28, and 35 days post-spray. At 21 days post-spray, a 53% psyllid mortality rate, an average of 5.9 CFUs per replicate (N=15), and a total of 88 CFUs were observed. Preliminary predictions are given for the interval on which PFR 97™ should be sprayed in citrus groves for efficient Asian citrus psyllid control and the impact of rain on spore retention.