Biochemical and molecular analysis of plants derived from embryogenic tissue cultures of napier grass (Pennisetum purpureum K. Schum)

We have investigated the extent of biochemical and molecular variation in 63 plants of napier grass (Pennisetum purpureum K. Schum.) regenerated from 3- to 24-week-old embryogenic callus cultures. The calli were derived from cultured basal segments of young leaves and immature inflorescences obtained from a single field-grown donor plant. The entire population was analyzed for the activity of 14 isozyme systems, but no qualitative variation was found at any of the loci examined. Similarly, no restriction fragment length polymorphisms ( RFLPs) were detected in the mitochondrial, plastid and nuclear genomes in a representative sample of regenerated plants. Our results confirm earlier reports of the genetic uniformity of plants derived from somatic embryos and highlight their value both for clonal propagation and for genetic transformation.