Investigating the effects of temperature on oil quality of Camelina sativa for bio-based applications

In Europe, the growing interest for camelina (Camelina sativa L. Crantz) as a new oil crop is in particular due to its unique fatty acid (FA) profile, characterized by high contents of polyunsaturated fatty acids (PUFAs, linoleic, C18:2n6 and linolenic, C18:3n3 >50%) and eicosenoic acid (C20:1n9 ~15%). With the general aim of introducing camelina in Europe, the objective of this thesis was to address the effects of temperature on the mechanisms of FA dynamics in camelina oil at different levels, covering agronomic studies as well as biochemical investigations. In the first study, camelina was grown in parallel in open field and in controlled environment conditions under different post-anthesis temperatures. Developing seeds were collected at fixed intervals and analyzed to determine total oil content and FA profile. The influence of temperature on C20:1n9 accumulation was generally lower than on PUFAs, but significant positive correlations between C20:1n9 and C18:3n3 were revealed. In the second study, further investigations were carried out on camelina developing seeds with a molecular approach: gene expression analysis and DNA sequencing were carried out on the principal genes involved in camelina FA metabolism. The definition of the “time frame” in which the main variations in FA kinetics occurred permitted in the third part, to develop empirical relationships based on the final oil quality of camelina grown in two different studies (multi-location and sowing date) in relation to the mean Tmin occurred during the “critical period”. The identified “critical period” was defined as the time of main variation for each of the principal FA. The improved knowledge of the relations between temperature and FA metabolism in camelina can increase understanding of the biochemical and physiological processes involved in their regulation, thus optimizing the agronomic management for this emerging and promising new oil crop for Europe.