This Is AuburnElectronic Theses and Dissertations

Application of molecular and bioinformatics approaches for sensory and quality attributes improvement in peanuts (Arachis hypogaea L.)




Jiang, Tao

Type of Degree

PhD Dissertation


Crop Soils and Environmental Sciences


As more consumers are paying attention to food quality and nutrients, obtaining desirable flavor and quality attributes become an important breeding objective for peanut. In this study, 120 accessions from the US Mini-core collection are utilized to investigate the population structure and genome-wide association studies (GWAS) are employed to identify its impacts on the market-trait association. In order to analyze the flavor and quality attributes (including sensory attributes, sugars, fatty acids, and tocopherols), this study first used the Affymetrix version 2.0 SNP array to identify a total of 17,232 high-quality single nucleotide polymorphisms (SNPs) from the U.S. peanut Mini-core Collection. 310, 474, 569 and 230 QTLs were identified related to sensory attributes, sugars, fatty acids, and tocopherols, respectively, including 14, 87, 105 and 73 significant QTLs for each profile. Among the significant QTLs, there were 4, 55, 86, and 49 QTLs with PVE higher than 15% for each profile, respectively (Table 3), indicating the high heritability of these traits. Consequently, genes were screened within 1 Mb of the significant QTLs and a total of 136 candidate genes were identified functionally associated with corresponding traits, including 13 genes associated with sensory attributes, 65 genes with sugars, 35 genes with fatty acids and 23 genes with tocopherols, respectively. Among these candidate genes, most of them are known to be involved in the biosynthesis and metabolism process of carbohydrates, fatty acids, and polyphenols. Furthermore, these results were confirmed by association mapping using SSRs and next-generation RNA-sequencing (RNA-Seq) two approaches. These findings provided a promising insight into the complicated genetic architecture of sensory and quality attributes in peanut and would promote the marker-assisted selection (MAS) in peanut breeding with seed flavor and nutrition quality.