The Mature Citrus Facility has made significant progress producing transgenics for clients as a service although we are attempting to make even greater progress. Since July 1, 2015, ~100 transgenics were produced with Agrobacterium, which exceeds previous production. The increase in productivity is primarily due to superior vectors with reporter genes, stronger promoters driving expression of the nptII selectable marker, and an increase in our micrografting efficiencies to 75 -77%. Our clients include Drs. Grosser, Dutt, Louzada, McNellis, Wang, and Mou. After optimizations for biolistic transformation of mature citrus have concluded, these transgenics will augment those generated with Agrobacterium. Our project objectives of increasing micrografting efficiencies, propagating transgenic events into replicates, applying for external funding, and service work have been met. Service work will continue for the same clients in the next funding cycle. A manuscript describing the biolistic transformation of immature citrus has been published, and another manuscript on the selection of transgenics without reporter genes in temporary immersion bioreactors is being submitted. An additional manuscript is in preparation describing the development of a quantitative in situ 4-MUG assay for transgenic, mature citrus shoots. The Mature Citrus Facility protocols have changed in an effort to speed the growth of mature scions. There is a tremendous growth advantage if rootstocks are not removed. After budding mature buds, rootstocks are left attached for the two flushes of stem growth. Mature buds will break and stems can be used in transformations within 6-8 weeks rather than 12-16 weeks specified in the earlier protocol. We continue to optimize for the PMI selectable marker using biolistics and Agrobacterium transformations. The number of nontransformed, escaped shoots appears to be significantly lower than with nptII as a selectable marker. Various treatments (cold treatments and hormone applications) were tried to in an effort to increase regeneration rates and transformation efficiencies in recalcitrant mature citrus scions, but none were satisfactory. However, a citrus DNA sequence drastically increases the number of transgenics in recalcitrant scions. An expression vector is being prepared to test in co-transformations. New breeder lines (3 sweet orange and 1 grapefruit) were introduced through shoot-tip grafting and are being budded for transformations. Protocols will initially follow those used for Hamlin and Valencia, but might still have to be optimized for these new cultivars. Some clients have asked for each transgenic event to be budded onto immature rootstock into replicates, and then flowering seems to be delayed. Every time mature citrus is budded onto immature rootstock, it is reinvigorated and this may potentially delay flowering. An experiment is being conducted to determine how many months flowering is delayed by grafting flowering tissue onto immature rootstock. This result will influence our recommendations to clients. Our lab will be moving to the packinghouse in July, 2016 in order to fix the AC in our current lab. This move will cause disturbances to plant production, but we will do everything within our power to minimize disturbances to the mature citrus transformation pipeline.