Project Number: 1931-21000-017-00
Project Type: Appropriated

Start Date: Apr 04, 2008
End Date: Apr 03, 2013

Objective:
1. Improve temperate stone and pome fruit quality traits. 2. Improve host-plant resistance of temperate stone and pome fruit to plum pox virus, tomato ringspot virus, prunus necrotic virus, and prune dwarf virus. 3. Develop a model biotechnology risk mitigation system and efficient genetic transformation protocols for Rosaceae.

Approach:
This project proposes the development of genetic solutions to the major problems affecting temperate tree fruit production and consumer acceptance of tree fruits through a coordinated effort utilizing the most appropriate technologies. The improvement of fruit quality will be approached through traditional breeding of novel genetic material, and also through the isolation and transgenic manipulation of key genes that control fruit development, stone formation, and ripening. The use of these diverse technologies will be coordinated in order to develop tree fruit varieties with improved flavor and firmness that is maintained post-harvest and investigate the possibility of creating marketable stoneless varieties. Improvement of fire blight resistance in pear will be approached through hybridization of existing fire blight resistant germplasm to develop new resistant cultivars that have high fruit quality. Pathogen- and host-derived resistance to stone fruit viruses will be incorporated into commercial quality cultivars through genetic transformation. Improved tree form for high-density production systems in peach will be approached through hybridization of peach germplasm with desirable tree growth habits such as columnar and semi-columnar with the aid of molecular markers that improve breeding efficiency. Pear growth habits will be manipulated through genetic transformation. Foundational work in genetic engineering and risk mitigation will facilitate the development of enhanced technologies that will help alleviate industry concerns over marketing genetically engineered crops. Improved plant material generated from both the laboratory and field will be evaluated in collaboration with the industry and consumer groups to facilitate its utilization.