Uptake and distribution of the growth retardant, aminozide, in relation to control of latera shoot elongation in Chrysanthemum morifolium

The uptake, stability and redistribution of the plant growth retardant, aminozide, in ‘pinched’ plants of Chrysanthemum morifolium Ramat. cv. Lemon Princess Anne were examined in relation to control of lateral shoot elongation. Foliar uptake was most rapid over the first few hours, and was almost complete within 72 h. More of the available aminozide was taken up by the young lateral shoots than by older foliage on the main stem. The aminozide content of entire plants generally remained constant over several weeks, indicating that the compound was relatively stable within the plant. The time scale and pattern of redistribution of foliar- and root-applied aminozide suggests that the compound may be translocated in both phloem and xylem. Spray application to young lateral shoots was as effective in controlling their elongation as application to all aerial organs. Basipetal transport of aminozide from lateral shoots was slight. The results are discussed in relation to the site of action of the compound and to its application in commercial practice.