Identification and qualitative characterization of high and low lignin lines from an oat TILLING population

To identify differences in seed lignin content, 520 randomly chosen independent lines were screened in mutagenized oat population and lines with the seed lignin levels ranging from 20 to 63 g kg−1 were identified. In the commercial variety Belinda, from which the mutated population was developed, seed lignin level was determined to be 41 g kg−1. In Assiniboia, a Canadian low lignin variety, it was found to be 21 g kg−1. To investigate if extracted lignin from the mutated lines were also qualitatively different from Belinda, two lines with the lowest and highest lignin levels were selected for structural analyses using XRD, UV and FT-IR spectroscopy. Results showed that there were significant qualitative differences in seed lignin in the mutated lines and in Belinda, and based on this, we predict that lignin from the mutated seeds will be more digestible in ruminant animals than Belinda seeds. This prediction was confirmed in preliminary in vitro digestion experiments.