This is the first year report of the two-year project on the genetic diversity and fingerprinting of Huanglongbing- associated bacteria. The project involves three objectives: 1). Analyses of historically and currently available literature data on HLB and identify important issues to address; 2). Study what microorganisms are involved in HLB in addition to what we currently know; and, 3). Use genomic information to study the variation of HLB-associated bacteria and their source of origins.