CHROMOSOME VARIATION IN CALLUS AND REGENERANTS OF PODOPHYLLUM-HEXANDRUM (PODOPHYLLACEAE)

The cytological status of callus and regenerants of Podophyllum hexand rum cultured in vitro for over a period of 3 years is reported. Calli maintained both on lower (0.5 muM) and higher (10 muM) 2,4-D, remained cytologically stable up to 18 months. With the long term (3 years) cu lture on higher 2,4-D both numerical and structural changes in the chr omosomes were observed. The calli maintained for 3 years on lower 2,4- D on the other hand retained both chromosome stability and regeneratio n potentiality. The regenerants in general showed normal mitotic compl ements. One of the regenerants from higher 2,4-D medium, however, show ed structural chromosome changes.