Flower and Volatile Oil Ontogeny in Boronia megastigma

Abstract The volatile oils of flowers of Boronia megastigma Nees. are important commercially but little has been published regarding their localization or the dynamics of their synthesis. In this study we examined the histochemistry, anatomy and volatile oil composition of the floral organs of plants from a native population by SEM. Lysigenous glands occurred in all organs except the stigma and androecium and were associated with the presence of α- and β-pinene and limonene in tissue extracts. These compounds increased in concentration throughout fruit development. Petals, stamens, staminodes and stigmas were glandular and contained phenolic deposits, a dense cytoplasm and prominent intercellular spaces. Extracts of these tissues contained dodecanol, β-ionone and dodecyl acetate, the concentrations of which were greatest at the time of stigma receptivity. The location and timing of their synthesis together with their biological activity suggests that these volatile oils may have a role in pollination.