Title: Employing microsatellite and SNP markers to track functional mutations and evaluate genetic diversity in the USDA Arachis germplasm collection Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 20, 2011
Publication Date: N/A
Technical Abstract: Peanuts (Arachis hypogaea L.) are nutritious because their seeds typically contain high amounts of oil, protein and other phytochemicals such as folic acid, tocopherol, and antioxidants; therefore, they are an important oil seed crop worldwide. The USDA Plant Genetic Resources Conservation Unit maintains over 10,000 Arachis accessions including both cultivated and wild germplasm. A core (831 accessions) and mini core (112 accessions) collection were established to represent maximum genetic diversity with minimal redundancy to help researchers rapidly mine important traits from a manageable sample set. The mini core, botanical varieties, and some wild relatives have been evaluated for allelic variation with microsatellite and SNP markers. The SNP markers were developed to detect wild type and mutant alleles in both ahFAD2A and ahFAD2B, which are known to affect oleic acid (C18:1) and linoleic acid (C18:2) accumulation. These ahFAD2 SNP markers were an effective tool utilized in a breeding program to select high oleic material in each generation and employed to quantify all ahFAD2 genotypes and their resulting phenotypes. Further, biochemical data such as total oil content, fatty acid composition, flavonoids, resveratrol, and morphological traits were also collected from the mini core accessions. The molecular markers and phenotypic trait data were employed to assess allelic variation, phylogenetic relationships, population structure, and association analysis of the mini core accessions. Genetic variation was revealed in the mini core and a few markers associated with phenotypic traits were identified. The information obtained will be useful for enhancing breeding efficiency and improving seed quality in peanuts.