Identifying molecular markers for breeding a future oil crop, Lepidium campestre

Sammanfattning: The cold hardy novel oil- and cover crop Lepidium campestre is currently being domesticated as a potential oil crop for the Nordic region. To achieve this objective, multiple traits have previously been identified as desirable to improve, including seed oil content and composition, and glucosinolate (GL) content. This study aims to find improve future breeding efforts for these traits, by identifying favourable markers in L. campestre, as well as evaluate related species for future interspecific hybridization. In line with this, major genes involved in the biosynthetic and degradation pathways of seed oil and glucosinolate were evaluated in 40 accessions of Lepidium with the aim of finding a significant association with polymorphisms and total oil content, oleic acid (OA) and erucic acid (EA) contents as well as total GL content, Sinalbin (Sb) and glucoallysin (Gl) contents. In total, 113 significantly associated markers were identified. Among these markers, 27 were identified as especially interesting, 13 markers with oil content, eight with oil composition (OA and EA), and six with GL content. In addition, relatives of L. campestre were evaluated for morphology, seed oil content, oil composition and glucosinolate content. Their phylogenetic relationship with L. campestre was also evaluated for use as potential candidates for interspecific hybridization. In this analysis two species with beneficial OA content were suggested for future crosses, L. hirtum subsp. calycotrichum and L. heterohyllum. An additional four species with beneficial oil-, OA-, EA- and GL-content were identified as interesting targets for future embryo rescue protocol adaptation, necessary to overcome breeding barriers. These include L. graminifolium, L. sativum, L. virginicum subsp. Menziesii, and L. perfoliatum.