Date of Graduation

Spring 2024


Master of Science in Plant Science (Biology)



Committee Chair

Chin-Feng Hwang


In the midwestern United States, the Vitis interspecific hybrid ‘Chambourcin’ is a very popular winegrape. Powdery mildew, caused by the fungus Erysiphe necator, is one of the primary causes of grape yield loss across the globe. Presently, specific genetic determinants for resistance to E. necator remain undiscovered in ‘Chambourcin’. To identify these factors, a controlled leaf disc assay was conducted for two years using the Automated Phenotypic System (APS) with 273 F1 genotypes from a cross of ‘Chambourcin’ and V. vinifera ‘Cabernet Sauvignon’. Additionally, a pioneer linkage map using the same number of ‘Chambourcin’- derived hybrids was constructed with 355 simple sequence repeats (SSR) and 1,394 RNaseH2- dependent amplicon sequencing (rhAmpSeq)-derived haplotype markers that clustered into 19 linkage groups. A quantitative trait locus (QTL) analysis indicated a resistance locus (here named Ren16) was discovered on linkage group (LG) 7 explaining 8.90 % – 12.57 % of the total phenotypic variance. The markers used in the study can be directly used for future marker assisted selection (MAS). Furthermore, the localization of powdery mildew resistance regions is crucial for gene identification and pyramiding, ensuring sustainable protection against pathogens.


marker-assisted selection, grapevine powdery mildew, simple sequence repeat, rhAmpSeq marker, candidate gene, QTL, REN16

Subject Categories

Bioinformatics | Viticulture and Oenology


© Achyut Duwadi

Available for download on Saturday, December 14, 2024

Open Access