Funding is now in place among all the partners of the International Citrus Genome Consortium (US, Brazil, Spain, France, and Italy) to move forward with the project to sequence a haploid citrus genome. DNA samples for sequencing have been prepared, and the strict quality control standards required by the sequencing centers (JGI in the US, Genoscope in France, and IGA in Italy) have been met. DNA samples have been shipped only to Genoscope and IGA at this point. The University of Florida and Brazilian interests remain in negotiations with JGI over contract language, before JGI can proceed with their portion of the sequencing project. Meanwhile, work has proceeded at the UF-CREC to produce sample materials needed for the microarray experiments planned, using Affymetrix GeneChips, a new array platform developed by the co-PIs at UF using Agilent technology, and for the cDNA platform available through our co-PI in Spain. To this end, two sets of plants of sweet orange, rough lemon, and Volkamer lemon, representing the more susceptible and more tolerant types respectively, have been inoculated with budwood from HLB-infected Carrizo citrange (Carrizo is resistant to CTV, so viral interaction complications will be avoided) in an environmentally controlled greenhouse. Samples of RNA have been prepared from all of the plants at regular intervals, to be used in microarray experiments. Plants have been observed for symptoms, and qPCR has identified some that were successfully infected. The HarvEST Citrus EST database is in process of being updated, to provide an improved database for gene expressions studies. The EST sequences from our colleagues in Brazil and Japan have all been downloaded and reassembled, increasing the number of publicly available citrus ESTs to more than 465,000. The plans to exploit genome sequence information for a better understanding of the interactions of citrus plants with the pathogen causing HLB are ultimately most dependent on having the genome assembled and annotated; for this reason, our main focus will be on accomplishing that goal, while continuing to establish the experiments and collecting the samples that will be used for subsequent microarray analyses and deep transcriptome sequencing.