SOMATIC EMBRYOGENESIS AND PLANT-RECOVERY FROM MATURE TISSUES OF OLIVECULTIVARS (OLEA-EUROPAEA L) CANINO AND MORAIOLO

A cyclic system of somatic embryogenesis from mature tissues of olive (Olea europaea L.) and subsequent plant recovery were developed. The p rimary embryos originated from morphogenetic masses derived from petio les of shoots regenerated from tissues of two micropropagated cultivar s: Canino and Moraiolo. The rejuvenation acquired by the shoots by reg eneration, directly from petiole tissues or indirectly from petiole ca llus, seems to be essential for the subsequent somatic embryogenesis i nduction. Cyclic embryogenesis, both from normal embryos or teratoma, was obtained on modified olive medium (OMe) plus 0.5 mu M; 6-dimethyla minopurine, 0.44 mu M 6-benzylaminopurine, 0.25 mu M 3-indolebutyric a cid and 0.42 mM cefotaxime. The production of normal embryos was highe r, faster and often more clustered on a filter paper liquid medium or on a media solidified with phytagel than with agar. The capacity to pr oduce continuous cycles of successive embryos has been maintained for over two years only in the dark, since the light inhibited embryo indu ction. The embryogenetic capacity was qualitatively and quantitatively enhanced by adding 0.42 mM cefotaxime. Mature embryos germinated easi ly by increasing the amount of liquid medium with shake culture. Altho ugh the majority of embryos appeared vitrified when transplanted to Ji ffy-7 pots, they subsequently grew normally and were similar to those derived from nonvitrified embryos. The plantlets obtained from somatic embryos appeared to be morphologically similar to those produced from axillary buds.