Axillary bud development in chrysanthemum

Each chrysanthemum cutting originates from an axillary bud. For an improvement of the cultivation of cuttings or more specific their quality, it is necessary that the development of an axillary bud can be controlled as good as possible. Axillary bud development can be distinguished into axillary bud formation and axillary bud outgrowth. The effect of assimilates, position and age of axillary buds, and temperature on formation and outgrowth of the axillary buds and the subsequent cutting quality was studied. Measured quality parameters of the cuttings were: freshand dry weight, diameter, number of leaves, leaf area, length, number of pith cells in a cross section and diameter of the pith.The effect of assimilates and temperature on axillary bud formation and subsequent cutting quality was only small. Differences that occurred were mainly due to differences in developmental stage and degree of inhibition of the axillary buds.On the other hand, axillary bud outgrowth and subsequent cutting quality can be influenced. An increase in number of leaves (assimilates) per axillary bud, by removing axillary buds, increased cutting quality. Position and age of the axillary buds also affected cutting quality when the outgrowth of the bud took place on the plant. However, the outgrowth of axillary buds separated from the plant was not influenced by age and position of the buds. Finally, decrease in temperature reduced axillary bud outgrowth but favoured subsequent cutting quality.The best way to improve cutting quality is increasing the amount of assimilates per outgrowing axillary bud andlor decreasing the temperature. Unfortunately, increasing cutting quality in these ways decreases the number of produced cuttings. An economic optimum for quality and number of cuttings should be found.