Adjunct Professor Adjunct Professor Blacksburg, Virginia, United States
Protocols were developed to determine infectivity, virulence, and overall mortality of commercialized entomopathogenic strains of fungi against the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae). Fourteen strains sourced and isolated from commercial formulations of blastospore and conidiospore suspensions, and three unaltered commercial formulations selected through this screening process were tested against a standardized strain in a controlled laboratory setting. A statistical ranking system was established in which top performing pathogenic strains are selected for further screening and field trials. Potter spray towers were utilized to deliver a range of doses of viable spores per milliliter of isolated strains, and a rate equivalent to 1x1012 spores per acre of unaltered formulations on adult D. citri in spray exposure bioassays. After a 7 day incubation period, mortality rates of the D. citri were analyzed against a standard, PFR-97® (Isaria fumosorosea; Apopka97 strain). Results provided insight into mortality, rate of infectivity, and susceptibility to infection. Eight strains tested exhibited significantly greater efficacy when compared to the standard. The two unaltered formulations of top performing strains, NoFly WP, BioCeres WP, (PFR-97 WDG as standard) were selected for use in field trial applications against ACP.
