Temperature and GA3 Effects on Emergence and Flowering of Potted Paeonia lactiflora

Abstract

Various durations of rooting at 15C and storage at 5.X and exogenous GA, (1000 ppm) application were used on dormant unrooted peony (Paeonia lactiflora Pall.) tubers of `Sarah Bernhardt', `Festiva Supreme' `Krinkled White', and `Scarlet O'Hara'. Four weeks of cooling were sufficient to break dormancy. Days to emergence, first bud color, and anthesis were reduced as the length of cold storage increased from 4 to 20 weeks. Height and number of shoots emerging per pot increased with increased cooling. All flower buds aborted when tubers were cooled for 20 weeks. When noncooled tubers were given a 1000-ppm GA, soil drench, shoots emerged within 7.5 days; untreated tubers failed to emerge after 5 months. When tubers were treated with GA,, all flower buds aborted.