ON THE ROLE OF ETHYLENE BIOSYNTHESIS IN FLOWER-BUD ABSCISSION OF LILIUM X 'ENCHANTMENT'

A high amount of flower-bud abscission was induced after exposing plants of Lilium X 'Enchantment' to a 7-day dark period at the stage where the largest flower-buds were 3 cm long. Spraying the plants with silver thiosulphate (STS) completely prevented this abscission. In a greenhouse experiment during winter time abscission was reduced from 94% to 17% by foliar sprays with STS. When plants with flower-buds of 3 cm long were placed in darkness for 5 days, a 10-fold increase in ethylene emanation from the buds was observed which did not occur when plants were sprayed with STS prior to the dark period.