2012 Annual Report 1a.Objectives (from AD-416): 1. Cultivation of "Ca. L. solanacearum" through in vitro and in planta approaches. 2. Morphological, physiological and genetic characterization of "Ca. L. solanacearum". 1b.Approach (from AD-416): 1. Identify and obtain "Ca. L. solanacearum" infected potato materials from fields in California. Maintain the infected potato in greenhouse. 2. Through grafting, transer the bacterium to different types of plants and evaluate their capacity to host the bacterium. 3. Variate in planta cultivation conditions to optimize bacterial growth. 4. Develop tissue culture, insect cell culture and in vitro culture methods for "Ca. L. solanacearum. 5. Use PCR and electron microscope to monitor the bacterial growth. 3.Progress Report: This research is in support of Objective 1.C. Cultivation and characterization of “Candidatus Liberibacter solanacearum”. Twelve cultivars of tomato were chosen for a variety of characteristics that included drought tolerance, heirloom status, number of days, greenhouse, hybrid, low acid, organic, processing, determinate/ indeterminate, leaf type, and fruit size. Seeds were planted. Forty days later, plants were inoculated by grafting of infected tomato shoots. Thirty of the 59 grafts were successful. A systematic evaluation for Candidatus Liberibacter solanacearum infection and host response to the bacterium is currently underway.