A Shift in Morphogenetic Pattern in Citrus Callus Tissue During Prolonged Culture

Abstract

Stem-callus type-B tissue of Citrus grandis was obtained from type-A mother tissue in prolonged culture. When both types were grown in the same medium containing zeatin + NAA, two different morphogenetic patterns were produced by them. In this medium, the type-B tissue formed numerous greenish globular bodies, which on subculturing in the same medium gave rise to a compact-nodular, greenish and slowgrowing tissue, subsequently differentiating numerous embryoids, whereas the type-A tissue formed numerous shoot-buds. Thus, during prolonged culture of stem-callus tissue a shift occurred in the morphogenetic pattern, i.e., from shoot-bud differentiation to embryogenesis, which could be evoked under the identical culture conditions.