Reversal of Heat-induced Resetting in Eustoma grandiflorum with Low Temperatures

Abstract

The effects of seedling age and temperature regimes and durations on the reversal of Eustoma grandiflorum (Raf.) Shin. heat-induced rosette formation were clarified. When E. grandiflorum seedlings were grown in a natural-light phytotron (600-800 μmol·m -2 ·s -1 ) for 4 weeks at 33/28C (12-h day/12-h night) from germination to the four true-leaf stage, the optimum temperature and duration required to break rosette formation was 15C for 4 weeks with continuous illumination (35 μmol·m -2 ·s -1 ). However, when seedlings were grown for 12 weeks at 33/28C from germination to the eight true-leaf stage. shoot elongation required 6 weeks at 10C.