THE ALTERATION OF BULB HORMONES CONTENT BY ENVIRONMENTAL STIMULI
This investigation was concerned with the separate and combined effects of temperature and water on the endogenous gibberellin (GA) content of Tulipa gesneriana L. The data showed that water interacted with temperature in influencing the GA content of tulip bulbs. Estimates of GA content based on the dwarf pea bioassay indicated that there was a thirty-nine-fold increase in GA in bulbs treated at 17°C wet when compared to a 17°C dry treatment, and an eighty-nine-fold increase in GA when bulbs were treated at 9°C wet than 9°C dry. On the other hand, a 9°C wet treatment resulted in a seven-fold increase in GA content over a 17°C wet treatment, while a 9°C dry treatment caused only a three-fold increase in GA when compared to bulbs treated at 17°C dry. The highest GA content was obtained in bulbs treated at 9°C wet. The removal of the basal stem-plate of bulbs grown at 9°C wet or 17°C wet resulted in a large reduction in GA content. The relative importance of temperature, water and root development on GA content of bulbs was discussed.
Aung, L.H. (1971). THE ALTERATION OF BULB HORMONES CONTENT BY ENVIRONMENTAL STIMULI. Acta Hortic. 23, 156-161