PRODUCTION OF EMBRYOGENIC CALLUS FROM NONEMBRYONIC EXPLANTS OF NORWAYSPRUCE PICEA-ABIES (L) KARST

Callus has been induced on needle and bud explants from 2, 6 and 26 ye ar old Picea abies (L.) Karst. trees. Seventy seven percent of the nee dle explants from the youngest material was productive compared to 0.2 % for the old tree. New embryogenic sections appeared in the non-embry ogenic callus derived from 2, 6 and 26 year old trees after prolonged culture and was promoted by the use of an established embryogenic call us line in a nurse culture system.