Date of Graduation

Spring 2016


Master of Science in Plant Science (Agriculture)


College of Agriculture

Committee Chair

Chin-Feng Hwang


The grape and wine industry relies heavily on sulfur and sulfur containing compounds to control the fungal disease powdery mildew (PM). Sulfur dioxide induces large-scale transcriptomic modification in the Eurasian grape species Vitis vinifera with little to no phytotoxicity. However, genetic factors contributing to sulfur sensitivity, characterized by vegetative necrosis and defoliation, remain undefined in North American grape species and their commercial hybrids. A mapping population, consisting of 147 F1 genotypes, was created by crossing V. aestivalis-derived ‘Norton’ and V. vinifera ‘Cabernet Sauvignon’ to identify the genetic basis for sulfur sensitivity in North American wine grapes. Clonally propagated F1 genotypes were fumigated with sulfur burners under greenhouse conditions. Association and linkage mapping were conducted using single nucleotide polymorphisms (SNPs) and simple sequence repeat (SSR) markers, respectively. A major quantitative trait loci (QTL) for sulfur sensitivity was detected on linkage group 14 (LOD=15). Identification of this QTL will allow future grape breeding programs produce commercially suitable hybrids, which do not display sulfur sensitivity, via marker assisted selection (MAS).


sulfur metabolism, sulfur sensitivity, marker assisted selection (MAS), oxidative stress, redox

Subject Categories

Plant Sciences


© Logan Michael Duncan

Open Access