Biochemical markers of embryogenesis in tissue cultures of the maize inbred B73

Abstract Stable embryogenic, organogenic and undifferentiated cell lines of the maize ( Zea mays L.) inbred B73 were used to assess the value of using isozyme analyses and the composition of secreted polysaccharides to identify embryogenic cells. Esterase, glutamate dehydrogenase, alcohol dehydrogenase and β-glucosidase all possessed developmentally regulated isozymes but only esterase and glutamate dehydrogenase could be used to distinguish between embryogenic and shoot-forming cultures. Embryogenic callus and suspension cultures secreted a musilagenous polysaccharide whose production was stimulated by 2,4-dichlorophenoxyacetic acid (2,4-D). This polysaccharide was different from root slime and corn hull gum and may be related to the ‘cementing layer’ in maize kernels.