SECRETIONS AND GYMNOSPERMS POLLINATION

This paper presents an historical review of the mechanisms of pollen c ollecting by the Gymnosperm ovules. Nucellar and/or epidermal secretio ns are involved in these mechanisms. Recently, the morphology, histolo gy and cytology of the secreting tissues in ovules and nucelli have be en explicited for some species using electron microscopy (transmission and scanning E.M.). The pollination drops were analysed for many spec ies. However, the pollen-ovule relations remain much less known than t he pistil-pollen relations in Angiosperms.