CHANGES OF ENDOGENOUS GROWTH SUBSTANCES DURING BULB MATURATION AFTER FLOWERING IN LILIUM ORIENTAL HYBRID 'CASA BLANCA'

Abstract

The content of abscisic acid (ABA), indole-3-acetic (IAA), and gibberellic acids (GAs) were identified during bulb maturation in mother and daughter scales of Lilium Oriental hybrid ‘Casa Blanca’. The bulbs were harvested at intervals 30 days after flowering. During bulb maturation, the ABA content of mother scales continuously decreased, while that of daughter scales decreased until 60 day after flowering (DAF) and then increased at 90 DAF. ABA content of daughter scales was lower than that of mother scales until 60 DAF, but was higher at 90 DAF. The IAA content of mother and daughter scales increased until 60 DAF and then slowly decreased thereafter. GA (3 + 4 + 7) content of mother and daughter scales was low until 30 DAF and then dramatically increased at 60 DAF. The IAA and GAs content of daughter scales was higher than that of mother scales. The cardinal point that shifted ABA, IAA, and GAs content during bulb maturation was 60 DAF. Thus, the ability or readiness of ‘Casa Blanca’ bulbs for reproductive growth occurred at 60 DAF.