1. Please state project objectives and what work was done this quarter to address them:
The purpose of the project is to characterize the distance of spread of citrus black spot (CBS) in groves in FL relative to the known source of inoculum. The information is fundamental to a data-based approach to delineating risk of spread under FL conditions based on current quarantine regulation. The goal of the first quarter of the first season was to establish some of the planned field experiments and obtain preliminary data. The collaborating citrus producer provided grove space, which is close to Immokalee, and in a citrus black spot (CBS) quarantined area. The experiments are being implemented in 3 different groves. Progress on the objectives is as follows:
1. Characterize spore production and splash dispersal distance for P. citricarpa: A preliminary experiment was initiated for this objective. Trap plants were placed at different distances from four CBS diseased trees to collect spores of the CBS pathogen, Phyllosticta citricarpa. The trap plants were replaced every two weeks following protocol. Preliminary qPCR analysis using established primers and probes indicated the presence of the pathogen on some sample leaves. The experiment will be continued throughout the year, to monitor spore production during the period of new fruit crop susceptibility. An additional experiment was initiated in an open area of the grove, placing diseased fruit in net bags on poles, with trap plants forming a cross in the four cardinal directions at different distances from the inoculum source. These samples have been taken and are being processed. The quantity of the pathogen dispersed different distances will be measured using qPCR.
2. Determine the likely distances of CBS spread: Trees were identified and marked for this experiment to be commenced in Q2.
3. Ascertain the role of leaf litter as a source of conidia: Trees were identified for this experiment to be commended in Q2.
4. Ascertain the spatial characteristics of CBS epidemics in Florida: For this objective, eighty-seven individual trees were assessed to quantify CBS aggregation as an indicator of distance of dispersal. Quadrats (0.75 m2) were used to count healthy and diseased fruit at five locations in each the upper and lower canopy (due to tree size it was not possible to include a mid-canopy height). So far, a total of 4,250 fruit have been assessed. These data have been entered into a spreadsheet. More trees will be sampled in Q2 and in Y2. Although analysis has not been completed, the indications are that the disease is aggregated, with more CBS-infected fruit in the lower parts of the canopy. Additional studies on the relationship between incidence and severity of the disease have been initiated to indicate the nature of the relationship. A high severity at low incidence is indicative of short distance spread (97 trees have been sampled so far).

2. Please state what work is anticipated for next quarter:
Next quarter will include continuing objective 1 studies, and extend these to include dispersal of a CBS surrogate in the experimental wind tunnel to better understand dispersal capabilities. Pathogen quantification using qPCR will be refined. Objective 2 and 3 studies will be commenced. Objective 4 data acquisition will continue. Data entry will continue.

3. Please state budget status (underspend or overspend, and why):
Budget status: The funding is in place and the funds are being used for project consumables and project personnel needs.