Cyanogenesis in somatic embryos and plantlets of cassava (Manihot esculenta Crantz)

A protocol was established for high frequency cyclic somatic embryogenesis and plant regeneration for the cassava variety PRC 60a. Linamarin content a nd Linamarase activity were determined in various tissues of secondary soma tic embryos and regenerated plants. Neither linamarin nor linamarase activi ty were detected in embryogenic callus and somatic embryos. The stems and l eaves of regenerated plants, however, contained variable amounts of Linamar in and linamarase activity whereas, in the root tissues, only Linamarin was detected. This study suggests that the pathway for linamarin biosynthesis may be absent or not switched on in the embryogenic callus and somatic embr yos. This system would be useful for investigating cyanogenesis in cassava. (C) 1999 Society of Chemical Industry.