Facultative winter accession ofCamelina sativa(L. Crantz) with early maturity contributes to understanding of the role ofFLOWERING LOCUS Cin camelina flowering

Abstract

Camelina is being developed as a winter oilseed cover crop. Early flowering and maturity are desired traits in camelina to allow for relay planting or seeding of a summer annual following camelina harvest. Here we report that while all winter biotype accessions of camelina have a functional allele of FLOWERING LOCUS C (FLC) on chromosome 20, there are also at least 20 previously characterized spring biotype accessions that have a functional FLC allele at this locus. We observed this by analyzing 76 of 222 camelina accessions that were resequenced by Li et al., 2020 as well as 11 additional accessions resequenced for this analysis. This discovery will inform marker assisted selection efforts that are underway to increase genetic variation in the genetically narrow base of winter camelina germplasm. Furthermore, we optimized a KASP genotyping approach that effectively differentiates winter camelina accessions from the spring accessions based upon a SNV in the FLC gene on chromosome 20. We also identified a facultative winter biotype accession of camelina (PI650163- 1) that has demonstrated two years of winter-hardiness and has flowered at least 7 days earlier than the common winter accession, "Joelle". A cross between Camelina sativa accessions PI 650168 (n=19) and PI 650163-1 (n=20) produced fertile progeny to the current F3 generation. Early maturing winter-hardy camelina will reduce stress on the subsequent soybean crop and improve cropping system yields. A principal components analysis of genetic diversity showed that three replications of this facultative winter accession clustered near the group of winter accessions.