‘Fastrack'—A Revolutionary Approach to Long-generation Cycle Specialty Crop Breeding

The American tree fruit industry is facing challenges of climate change, reductions in available labor, the need for reduced chemical inputs, the spread of exotic pests and pathogens, and consumer demands for improved fruit quality. To meet these challenges the development of new improved varieties is more vital than ever. Yet, fruit tree breeding remains a slow and costly process that has changed little over time. Limitations include long juvenility periods which can last 3–10 years or more, the need for large land areas that incur significant field costs, and yearly limitations on flowering and fruiting related to dormancy. Recently, research has focused on marker assisted selection (MAS), germplasm characterization, and genetic engineering (GE) as means to advance tree fruit breeding. However, the impacts of these strategies on breeding are all still limited by the inherently slow generation cycles of fruit trees. To address this problem, we have developed a system to shorten the breeding cycle of fruit trees and other long-breeding-cycle crops. We have overcome the juvenility and environmental limitations of flowering and fruiting by incorporating a gene that induces trees to flower and fruit early and continually. In plum, the crop with which we are now working, we have reduced the generation cycle from 3–7 years to less than one year. We call this rapid breeding system “FasTrack”. The system will allow for the rapid incorporation of important traits into plums and other long-generation-cycle crops, and then in the final generation, when substantial improvements are clearly evident, only seedlings that do not contain the early flowering gene would be selected.  These trees would not be genetically engineered. The selected trees may then be used directly as new varieties, or improved lines for further breeding. Such an approach would provide tree fruit and other long-cycle crop breeders with the ability to respond to new market demands, climate changes, and invasions of new diseases and pests in a way never before possible.