Growth and flowering responses of Anigozanthos hybrids influenced by plant age, temperature, and photoperiod treatments

Abstract

Growth and flowering responses of Anigozanthos hybrids, ‘Regal Claw’ and A. manglesii × A. flavidus, were investigated starting from in vitro propagated propagules. Flowering of 9-week old ‘Regal Claw’ was less than 50% from the main fan (MF) when plants received 21.0°C during day and 13.0°C at night (21.0/13.0°C, day/night). Flowering of 20-week old ‘Regal Claw’ and A. manglesii × A. flavidus hybrids either from the MF or the lateral fans (LF) was accelerated when plants received 21.0/13.0°C regardless of photoperiod treatment. Flowering from the lateral fans was accelerated when plants received 8 hours of long day photoperiod (LD) treatment as a day-extension provided from incandescent light bulbs at 21.0/15.5°C and 21.0/18.0°C. Fewer than 2.5 total branches per inflorescence were produced from the MF grown at 18.0°C as compared to more than 4.0 total branches produced at 13.0°C. Plants must be 20-week old to flower from both the MF and the LF. The optimum temperature for early flowering and for an increased quality of cut flowers was considered to be 13.0°C, and at this inductive night temperature for flowering, ‘Regal Claw’ and A. manglesii × A. flavidus are considered as a day neutral, while at 15.5°C and 18.0°C, they are considered as a quantitative long day (LD) plant.