Stimulation of Basal and Axillary Bud Formation of Container-grown Hybrid Tea Roses

Abstract

Abstract Two plant growth regulators, 6-benzylaminopurine (BA) and sodium salt of 2,3,4,6-bis-O-(1-methylethylidene)-a-L-xylo-2-hexulofuranosonic acid [dikegulac-sodium (DS)], were applied separately to container-grown two-year-old hybrid tea rose cultivars ‘Honor’, ‘Peace’, ‘Tournament of Roses’, ‘Touch of Class’, and ‘Prima Donna’ to study the effects on basal and axillary shoot production. Four rates of BA (0,75,125 and 250 ppm) or DS (0,250,500 and 1000 ppm) were applied as drenching sprays to the graft union or with floral foam applied basally or to the top of a cut cane. ‘Tournament of Roses’ had the greatest number of basal shoots when BA was applied at 75 ppm to a cut cane with a floral cube. ‘Peace’ and ‘Prima Donna’ had the greatest number of basal shoots when BA was applied at 250 ppm to a cut cane with a floral cube. Axillary shoots increased on ‘Honor’ when BA was applied as a basal floral foam. DS increased axillary shoots for ‘Peace’ only when applied as a drenching spray to the bud union. Otherwise, DS did not increase basal shoots for any other cultivar regardless of application method and rate. Neither chemical nor application method consistently promoted basal and axillary shoots in all five cultivars.