Lipid profiles of a diverse collection of Corylus species and interspecific hybrids

Hazelnuts (Corylus sp.) are a low-input, perennial crop that hold potential as a source of healthy culinary oil and feedstock for biofuels. Until recently, production of hazelnuts in the eastern United States was limited due to the fungal disease eastern filbert blight (EFB). Over the past several years, a number of sources of resistance to EFB have been identified and are being used in breeding. To date, however, little has been done to characterize the oil content and lipid profiles of these EFB-resistant breeding parents. In this study, the total kernel oil content and fatty acid profiles of four C. avellana cultivars were compared to nine diverse, EFB-resistant Corylus accessions representing three wild species (C. americana, C. heterophylla, and C. colurna) and various interspecific hybrids with C. avellana. Results showed that, on average, the wild/interspecific hybrid accessions had a lower kernel oil content - 60.3% - than the pure C. avellana cultivars - 67.2% - although there was some variation across accessions. Results also showed that the 13 accessions had a relatively uniform fatty acid profile, which was comprised mostly of oleic acid (~80%) and linoleic acid (~11%). Linoleic acid content was found to be more variable than oleic acid content. The relatively high kernel oil content and consistent fatty acid profile (high unsaturated/saturated FA ratio) suggest that multiple hazelnut species may be ideal for use as both a bio-fuel feedstock and a culinary oil. Minor (or simple) selection of breeding parents would help overcome the slight oil content deficiencies and allow for the use of wild species in the development of new, more widely adapted cultivars.