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"RosBREED focuses on sequenced," Gasic said, "but it's just a string of nucleotides until it's found what pieces of the genome govern what traits." The genome sequence bridging the gap between genomics knowledge and breeding application." —Ksenija Gasic was published April 1 last year by a team led by molecular geneticist Dr. Bryon Sosinski at North Carolina State Uni- versity in Raleigh, North Carolina. The DNA sequencing was done on a Lovell tree located not far from Gasic's new plantings at Clemson's Musser Fruit Research Farm. Clemson received about $400,000 of the RosBREED money to support Gasic's work and also that of Dr. Greg Reighard, who is an authority on fruit tree genetics and peach rootstocks. Ramping up This year, Gasic is ramping up her program. The first year, she created 1,200 hybrid seedlings, the next year 1,700. This year, she planted 8,000. Without markers to improve breeding efficiency, she will have these 11,000 trees to evaluate for at least two fruiting seasons in the field. With markers, superior seedlings with trait combi- nations she is looking for could be selected prior to field planting, therefore reducing the number of trees planted in the field and improving breeding efficiency. Other key traits that are important to her are fruit size, flavor, nutri- tional content, blush—red color of the skin—and disease resistance. In the RosBREED project, the four participating peach demonstration breeders—Tom Gradziel, at University of California, Davis; David Byrne at Texas A&M; John Clark in Arkansas; and Gasic at Clemson—have common goals such as maintaining and improving fruit quality (including flavor, firmness, and appearance), produc- tivity, size, and season extension. These target traits are complemented with specific needs of local areas—ease of processing, disease and pest resistance, a greater diver- sity of fruit types, and adaptation to chill zones. Gasic's goal is to produce about 3,000 seedlings a year. She does much of the crossing work herself, emasculating flowers and applying pollen by hand. Pollen, because it doesn't transmit diseases like plum pox, can be obtained from other places in the world, so she taps into gene pools in Serbia, Brazil, Italy, and other places where peaches are grown. She has a doctoral and a master's student working with her, as well as undergraduate students and a research technician. Peach pits, cleaned and stratified, are planted in the greenhouse and hybrid plants are grown over the winter. In March and April, they're moved outside into fields. The next year, some flowers will appear and result in fruit. "Once the tree bears fruit, it usually takes two years to decide whether a seedling should be kept and moved to the next stage. About five percent make that cut," she said. Gasic would love to improve efficiency of this tradi- tional way of doing things and is looking forward to dis- covery of more markers and more tests that can be done much earlier in the breeding process. • www.goodfruit.com GOOD FRUIT GROWER NOVEMBER 2011 37