1a. Objectives (from AD-416)
To develop and test a fruit tree rapid-cycling breeding program and to develop novel plum breeding germplasm.
1b. Approach (from AD-416)
Early flowering transgenes will be utilized to develop a rapid-cycling breeding system to dramatically shorten plum generation time. Using this approach, improved plum germplasm with Plum Pox Virus (PPV) resistance and high sugar control will be developed. "Specialty Crops Research Initiative Proposal"
3. Progress Report
The overall objective is to develop a management protocol to optimize and control flowering and fruit production on early flowering plums and to test the system in a breeding program. Temperature, daylength, and different dormancy induction treatments were varied using clonally propagated lines of early flowering plums. Growth, as well as flowering and fruit production, were measured. The results have given rise to a system that allows flower and fruit production in the greenhouse. Pollen was collected from California germplasm identified as having high sugar potential, as well as standard cultivars 'Improved French', 'Sutter', 'Muir Beauty' and 'Tulare Giant'. Pollen compatibility was tested with three different lines of early flowering plums with varying results. Additional pollinations were made with the successful pollens in order to generate early flowering California germplasm. 'Sutter', 'Muir Beauty', and 'Tulare Giant', all commercial quality plums, were transformed with a gene for early flowering. Successful plants are being tested for the early flowering trait. The ADODR has monitored activities through emails, meetings, and calls.