Growth and metabolism of Ricinus communis endosperm in tissue culture

Abstract

Endosperm tissue from both developing and germinating castor oil seeds (Ricinus communis L.) was grown as a callus in tissue culture. Callus growths were established from endosperm explants (without embryo) at all stages of seed development except from the quiescent unimbibed seed. Best tissue culture growth was observed with endosperm tissue obtained from seeds that had been germinated for 2 days.The lipid reserves diminished in all endosperm tissue which had been established on culture from germinating seeds but the rate of breakdown was much slower in cultures from 0-day germinated seeds. Glyoxylate cycle activity, as tested by acetate-1- and -2-14C incorporation, was not evident in long-term cultures.The process of lipid accumulation found in normal developing endosperm (24 to 36 days after fertilization) was not retained in culture but was replaced by a process resulting in the rapid loss of the already accumulated oil reserves.As far as could be determined the in vivo biochemical capabilities of the castor bean endosperm were not retained for a lengthy period in the tissue culture conditions used.