The Growth and Development of Anthurium andraeanum Lind Flower Before and After Emergence

The red commercial cultivar, Anthurium andraeanum ‘Kaumana’ flower growth and development before and after emergence in the generative phase was studied. Before emergence, the anthurium flower was seated at its subtending leaf petiole base and enclosed by two tightly rolled stipules. The smallest flower bud that could be seen was about 0.3 cm long with its subtending leaf still in the leaf sheath and was about 4.5 cm when it was ready to emerge from the petiole base. This period took about 80 days. A slow growth period, when the flower bud was 0.8 to 1.0 cm long, occurred just after the subtending leaf emergence and when the subtending leaf petiole was in its rapid elongation period. Flower bud growth resumed after the subtending leaf blade unfurled and became autotrophic. Spathe color development started about 28 days before emergence when the flower bud was about 50% of the emergence bud length. The two lobes were the last to develop. They were visible when spathe color started developing. At flower emergence the spathe was 80% red, with the lobe still white. Flower stalk elongation started 28 days before flower emergence. Flower stalk growth was sigmoid-shaped with the maximum growth rate 21 days after emergence. Flower spathe growth had a double sigmoid growth curve. The spathe was tightly furled for about 35 days after emergence. The spathe unfurled after the flower stalk had reached its maximum growth rate. Spadix growth study was possible only after the spathe was unfurled and matured from the base to the tip. Spathe lobe was not red until 7 to 10 days after flower emergence. Young subtending leaf blade (7 to 14 days after leaf emergence) had a negative net photosynthetic rate. Removal of this leaf blade promoted earlier flower emergence by 18 days. Soft green leaf (25 to 30 days after emergence) had a slightly positive net photosynthetic rate, and the removal of this leaf resulted in 11 days earlier flower emergence. A mature subtending leaf had the highest net photosynthetic rate, and its removal had little effect on flower emergence