THE INFLUENCE OF GIBBERELLIC ACID ON GROWTH AND FLOWERING OF SOME ZANTEDESCHIA CULTIVARS GROWN OUTDOORS

The research was carried on rather small tubers (55-60 g) of four Zantedeschia cultivars: ‘Black Magic’, ‘Pink Persuasion’, ‘Cameo’ and ‘Florex Gold’. The aim of the experiment was the evaluation of gibberellic acid (GA₃) treatment, tuber dips in 0, 50 and 100 mg L^-1 GA₃ solutions before planting.
Plants were grown outdoors, in containers during summer months, from June to October.
The GA₃ application generally delayed Zantedeschia flowering, however, the reaction of cultivars were different.
The earliest flowering was observed on the cultivar ‘Florex Gold’, 54 days, then ‘Black Magic’ and ‘Pink Persuasion’, 58 days.
The latest flowering was ‘Cameo’, after 63 days.
As expected GA₃ application increased flower yield in all varieties by 2-3 times.
The highest yield was obtained on ‘Florex Gold’ and ‘Pink Persuasion’, 5-6 flowers/tuber.
The cultivars ‘Cameo’ and ‘Black Magic’ gave 3-4 flowers/tuber.
The GA₃ application did not affect the flower weight.
Fresh weight of tubers, lifted after flowering, of cultivars with shorter flowers as ‘Florex Gold’ and ‘Pink Persuasion’ decreased, and increased in cultivars with long, big flowers (‘Black Magic’ and ‘Cameo’).

IX International Symposium on Flower Bulbs

J. Treder

calla lily, flower yield, GA₃, tuber weight

https://doi.org/10.17660/ActaHortic.2005.673.94