EFFECTS OF LIGHT AND HORMONES ON REGENERATION OF CRASSULA ARGENTEA FROM LEAVES

Plantlet regeneration from leaf segments of Crassula argentea was studied under variable light and hormone treatments. The effects of two hormones (indole 3-acetic acid and isopentenyl adenine at 10⁻⁴ to 10⁻¹⁰ m ) and photoperiods of 8 (short days) or 16 hr of light (long days) were examined. Exogenously applied hormones had little stimulating effect on regeneration but were consistently inhibitory at 10⁻⁴ m . Short days and continuous darkness caused the greatest promotion of regeneration. Prolonged short-day growth periods prior to culturing caused an increasingly greater regeneration response.