Caula A. Beyl1, Cary A. Mitchell1
1Department o f Horticulture, Purdue University, West Lafayette, IN 47907
Tóm tắt
Abstract
Elongation growth of Chrysanthemum morifolium Ramat. cv. May Shoesmith was inhibited by daily shaking with an automated mechanical device. The dwarfing effect was more pronounced if plants were shaken at 0800 than at 1600 or 2400 hours. The longer the duration of stress, the greater the growth inhibition. Thirty seconds to 2 minutes of stress per day were required for significant dwarfing, with saturation of the effect at 4 to 5 minutes. Four-minute treatments 2 to 4 times daily maximized the stress response. Node number, fresh weight, and dry weight were reduced by shaking, but dry-to-fresh weight ratio was increased. Reciprocity applied to the stress responses in that one 4-minute stress per day had the same growth-retarding effect as four 1-minute stresses. Shaking did not significantly affect flower bud initiation, flower size, or floral keeping quality.
