Submitted to: American Society of Enology and Viticulture Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/11/2005
Publication Date: 7/12/2005
Citation: Lu, J., Huang, H., Ren, Z., Hunter, W.B., Dang, P.M. 2005. Development of grape EST-SSR markers for genotyping and mapping disease resistant genes. American Society of Enology and Viticulture Annual Meeting Abstracts. Interpretive Summary:
Technical Abstract: We have sequenced 25,000 ESTs from a clone of Vitis shuttleworthii grape that has been using extensively in several grape breeding programs for improving disease resistance in the southeastern United States. To develop molecular markers for marker-assisted grape breeding and genome typing, SSRs from the V. shuttleworthii sequences and V. vinifera ESTs in the public domain were screened. Of the 12,056 V. shuttleworthii ESTs, 401 putative SSR loci were identified. From a total of 153,139 grape ESTs retrieved from NCBI (7/10/04), 4,967 were identified as SSR ESTs. The SSR-EST represented about 3% of total grape ESTs, which is consistent among ESTs generated from different Vitis species. Trinucleotide repeats are the most dominant SSRs found among all the Vitis species, ranging from 45 to 55 % of their total SSRs, respectively. The majority of trinucleotide repeats in grape are six and seven unit repeats. Among the tri-SSR repeats, CAA/GTT and ACC/TGG were the most abundant tri-SSR. Functional annotation revealed that 14% of the SSR-ESTs are related to disease-resistance. PCR primers were synthesized from a selected set of SSR-ESTs (putative function of disease resistance). Among the 100 primers screened, two-third were amplifiable, of which 60% generated polymorphism while 40% gave no polymorphism among eight Vitis species /varieties tested. The polymorphic EST-SSRs will be very useful for tagging grape disease resistant genes.