Contribution à l’Étude cyto-physiologique du stigmate: I. Les étapes observées durant les processus glandulaires chez une Oleaceae: Forsythia intermedia Zabel

Lipochemistry of the progamic stage of a self-incompatible species: Neutral lipids and fatty acids of the secretory stigma during its glandular activity, and of the solid style, the ovary and the anther in Forsythia intermedia Zab. (Heterostylic species)

Chromatographic (thin-layer, gas column, column chromatography) analyses of neutral lipids and fatty acids of reproductive tissues of Forsythia intermedia Zab., a self-incompatible species, were performed with two objectives in mind: 1. To determine whether there is a qualitative evolution of the different classes of lipids and fatty acids that could be correlated with the three functional stages observed during previous histochemical and ultrastructural studies. The stigmatic exudate and intracellular accumulations consist mainly of neutral lipids. 2. To compare the lipid composition of the stigma (both "thrum" and "pin" forms) with that of the style, the ovary, and the anther, and to investigate the possible existence of a stigma-specific lipid compound. Stigmatic neutral lipids are found mostly in a glyceridic mixture probably containing hydrocarbons and terpenes. The fatty acids identified are between C:7 and C: 12, with the maximum unsaturated form being a C: 18. During the secretory process there is no great qualitative diference between the neutral lipids and fatty acids found in the stigmas of "thrum" and "pin" forms. Sterols are present in styles, ovaries, and anthers, but not in stigmas. They represent the only difference in the lipid composition of these various floral structures.