Variabilité des teneurs et compositions des composés mineurs dans l’huile de tournesol au cours du développement du capitule

Abstract

1 Universite de Toulouse ; Ecole d’Ingenieurs de Purpan ; Laboratoire d’Agro-Physiologie ; 75, voie du TOEC, BP 57611, F-31076 Toulouse Cedex 03, France 2 ONIDOL, Organisation nationale interprofessionnelle des oleagineux, 12, avenue George V, 75008 Paris, France 3 ASEDIS-SO, 39, chemin Virebent, 31200 Toulouse, France 4 COGNIS-France, Usine d’Estarac, 31 360 Boussens, France Abstract: Sunflower oil is rich in polyunsaturated fatty acids and in minor components (1 % of the oil fraction) including phytosterols, tocopherols, waxes and others components. This study evaluates the content and composition of the phytosterols in four sunflower hybrids during two growing seasons (2002 & 2003) and in seven more hybrids in a multilocal study in 2003. The phytosterol content in the maturing seeds was followed from flowering stage till full maturity. The kinetics of phytosterols accumulation was similar to that of fatty acids : a rapid increase until 25 Days After Flowering DAF and a stabilization after 50 DAF. However, the temperature during the seed development induced changes in the phytosterol content, since the total amount of phytosterols was significantly increased by high temperatures in some hybrids. On the other hand, the comparison of phytosterol content in the 11 hybrids tested in 2003 shows significant differences in phytosterol content between hybrids and low location X hybrid interaction. In this study the environment effect was the major source of variation. This study shows that phytosterol content in sunflower oil can be promoted though combined action on selection and growth conditions.