DIRECT SOMATIC EMBRYOGENESIS IN LEAVES OF CICHORIUM - A HISTOLOGICAL AND SEM STUDY OF EARLY STAGES

Leaves from 2-month-old in vitro grown plantlets of a clone of Cichorium placed in agitated liquid induction medium at 35-degrees-C in the dark produce embryoids after 5 days of culture, without synchronization. Vascular sheath parenchyma cells react first, but every mesophyll cell is potentially embryogenic. Single cells show an early patchy callosic wall and undergo dedifferentiation. With SEM the cells of those proembryoids just emerging through the epidermis are seen to be linked by a fibrillar network, the nature of which is discussed. Four FITC-labelled lectins were tested; only. DBA shows embryogenic specificity.