Fertile pea plants regenerate from protoplasts when calluses have not undergone endoreduplication

Large numbers of viable protoplasts were isolated and cultured from five pe a genotypes. Calluses obtained (percent final plating efficiency (% FPE) = 0.65-2.82% of initially plated protoplasts) exhibited great differences in proliferation and regeneration competence between and within genotypes. Flo w cytometric analyses showed the occurrence of endoreduplication processes correlated with such differences, and could serve as a tool for the early p rediction of plant regeneration competence from protoplasts. Fertile plants were produced only from calluses with a normal DNA level. (C) 2000 Elsevie r Science Ireland Ltd. All rights reserved.