|Walker,, Andrew - UC DAVIS|
Submitted to: CDFA Pierce's Disease Control Program Research Symposium
Publication Type: Proceedings
Publication Acceptance Date: October 26, 2007
Publication Date: December 1, 2007
Citation: Ramming, D.W., Walker,, A.M., Lin, H. 2007. Breeding pierce's disease resistant table and raisin grapes and the development of markers for additional sources of resistance. In: CDFA Pierce's Disease Control Program Research Symposium. p. 271-273. Interpretive Summary: The spread and severity of Pierce’s disease has been increased with introduction of the glassy-winged sharpshooter into California. Table and raisin grape varieties grown in California are very susceptible to Pierce’s disease. Resistance is being combined with high quality table and raisin grape germplasm by hybridization with different sources of Pierce’s disease resistance. The first BC3 crosses in the V. arizonica source of resistance were made this year. This generation is 93 percent V. vinifera. The use of molecular markers has simplified identification of PD resistant individuals from V. arizonica. The resistance based on molecular markers continues to segregate in a 1:1 ratio in V. arizonica BC2 families. Seedless table and raisin grape selections with PD resistance and improved fruit quality have been made. Thirty polymorphic SSR primers have been identified in the BD5-117 family in the search for molecular markers from sources of resistance other than V. arizonica.
Technical Abstract: Fifteen BC3 and two BC2 crosses between V. arizonica source of Pierce’s disease (PD) resistance and seedless table and raisin selections were made and produced 3,396 berries, 4,459 ovules and 1,840 embryos. Two additional seedless and two seeded crosses were made. Ten 2006 BC2 families (V. arizonica) consisting of 765 individuals were screened in the seedling stage in the greenhouse with SSR markers for resistance. A total of 262 were resistant and planted in the field. Resistance and susceptibility segregated in a 1:1 ratio. Greenhouse screening of the BC2 raisin family 04-5554 confirmed that 17 of 18 individuals with resistant markers were resistant. Four of the resistant fruiting plants had small aborted seed similar to raisin cultivars. An additional 33 plants and 241 embryos were produced to increase the C33-30 x BD5-117 family for new maker development. Its parents and resistant and susceptible bulks were screened with 424 SSR primers of which 30 were confirmed polymorphic.