1a. Objectives (from AD-416)
The project addresses the Specialty Crop Research Initiative (SCRI) stated need for "Developing innovative breeding systems that improve the speed and flexibility to deliver unique cultivars to meet future challenges". The proposed "FasTrack" will be an advanced fruit tree breeding system that uses transgenic early and continually flowering trees to overcome the limitations of juvenility and dormancy, producing the first generation in one year versus the normal three to seven years. Unlike conventional breeding, "FasTrack" crosses will be done in the greenhouse, and only the non-transgenic individuals from segregating populations will be released to the field. We propose to implement "FasTrack" using a transdisciplinary, whole systems approach to address the short- and long-term challenges facing the $200 million dollar California dried plum industry. Two industry specified traits, Plum Pox Virus (PPV) resistance and high sugar content, will be rapidly incorporated into industry standard germplasm. Molecular markers will be used to further improve the efficiency of the "FasTrack" rapid backcross breeding scheme. The economics of "FasTrack" breeding versus conventional breeding will be compared in two participating plum breeding programs. The project progress will be monitored by an advisory board and will be directly communicated to Prunus breeders, industry representatives, and scientists. Through consultation with domestic and foreign regulatory agencies, a comprehensive plan will be developed to determine if "FasTrack" progeny are exempt from regulation and accepted as standard varieties. Environmental and consumer-oriented NGOs will be consulted to address the public acceptance of "FasTrack" technology and pave the way for future commercial releases.
1b. Approach (from AD-416)
The "FasTrack" breeding project proposes to deliver an advanced biotechnology to an existing industry supported plum cultivar development program. "FasTrack" breeding technology will be developed to specifically meet the needs of the California dried plum industry by integrating the system with the major California dried plum industry's breeding program and targeting traits highly desired as test cases. The probability of success of this project is highly based on the long-term expertise and experience of the project investigators in plum breeding and transgenic technology of plum. This will ensure that the benefits of "FasTrack" technology are realized and lead to long-term commitments by the California dried plum industry, while at the same time, strengthening the plum "FasTrack" system’s role as a model for other tree fruit industries to follow.
3. Progress Report
'FasTrack' breeding is a system to create a generation every year. In order to optimize the diversity, follow each parent's contribution, and follow specific traits, a series of molecular markers is necessary to mark each group. Towards this end, leaves were collected from all of the California germplasm that is being used in the 'FasTrack' program and all of the early flowering plum lines currently being used. This will be used to find markers for the parental lines. Material for looking for markers for the high sugar trait of interest was collected from a cross of high sugar germplasm, as well as from other high sugar germplasm from the California collection. Leaves from 'Honeysweet' plum, which carries the Plum pox virus (PPV) resistance, were also collected. DNA was extracted from these leaves in preparation for screening all with existing SSR DNA markers that mark all of the segregating sections of the peach genome. The ADODR has monitored activities through emails, meetings, and calls.