Maize Propagation and Breeding Through the Culture of Reproductive Organs

Abstract

Mass clonal propagation can be achieved via multiple shoot induction from organized and unorganized systems (Hisajima et al. 1986; Hisajima 1987). The organized systems include shoot tips, stem segments, nodal regions, dormant buds, hypocotyls, and other differentiated organs or tissues. The unorganized systems include callus cells, suspension-cultured cells, and other dedifferentiated cells. It is likely that plants regenerated via auxiliary shoots from organized systems are not genetically deviant from the mother plants, and that aberrant plants are not unusual among plants regenerated via adventitious shoots from unorganized systems. At present, the idea is widely accepted that plant propagation via organized systems is adequate for vegetative propagation of industrial crops, and that regenerated plants via unorganized systems are important as new gene resources. Usually, meristems, shoot tips, and other vegetative organ/tissue of elite plants seem to be selected as original inocula for industrial mass clonal propagation of desired genotypes. Seeds and embryos (reproductive organs) seem to be less often selected as original inocula of clonal propagation because of their genetic Hybridity. Limited reports deal with micropropagation by seed/ embryo culture.