Contribution à l’étude de l’effet des températures basses sur la composition en acide gras de l’huile des akènes de tournesol (oléique et classique)

The climatic conditions of 2003 namely high summer temperatures induced atypical sunflower fatty acids profiles. The linoleic content of the oil was significantly lower that the codex values (60%), whereas the oleic concentration was high (40%). The authors demonstrate that the effect was due to the mean minimum temperature rather than the mean temperatures during the ripening period. The data fit well with a linear model established for two years. The period of sensitivity to temperature was between anthesis + 10 days and anthesis + 30 days. The model was tested on classical sunflower in 2003 and 2004 and on an oleic variety in 2002 and 2004.