1a.Objectives (from AD-416):
Identify alternative hosts for HLB, focusing on likely reservoirs in Florida and determinethe effects that alternative hosts play on the biology of the pathogen.
1b.Approach (from AD-416):
Ten to twenty potential rutaceous alternative hosts will be inoculated by psyllid and grafting (when possible). Infected plants will be identified by PCR, and used as a source for back inoculations to sweet orange. A limited sub-set will be tested for effects on the pathogen and the vector, with an emphasis on pathogenicity and transmission characteristics.
The objective of this project was to investigate the susceptibility of Citrus related hosts of Huanglongbing, especially for Candidatus Liberibacter africanus (Laf) and Ca. L. americanus (Lam). Isolates of Laf and Lam were maintained in sweet orange plants and colonies of the Asian citrus psyllid were maintained in our BSL 3 biosecurity facility. Test plants were supplied from the University of Florida. All test plants were assayed before their use in host range studies. Host range studies were completed on four species, Murraya paniculata, M. exotica, Bergera koenegii, and Xanthozylum beechyanum with Ca. L. asiaticus (Las) and are being conducted with Laf and Lam. Additional plant species will be tested as we obtain them. Knowledge of alternative hosts for HLB and the psyllid vector are important in developing control strategies for this destructive disease.