Flowering of Chrysanthemum under non-inductive long days by gibberellins and N(6)-benzyladenine.

The flowering and inflorescence development of Chrysanthemum morifolium cv. Pink Champagne under non-inductive long days was promoted by exogenous application of GA5, GA3, GA4+GA7 or GA9 in combination with the cytokinin, BA. The combination of BA and GA5 was highly effective, BA and GA3 moderately effective. Applications of the GAs alone or BA alone also resulted in some flowering, with GA3 and GA5 being most effective. In general, the effects of GA and BA were synergistic, and the concentration of both growth substances was a limiting factor with regard to the number of plants flowering under long days. Only the concentration of GA was a limiting factor for inflorescence development, however. Simultaneous application of indole-3-acetic acid reduced inflorescence development in most treatments. Development to the stage of anthesis was in no case effected.