EN
Detached leaves or shoots used f or floral arrangements, should preserve their decorative values at least as long as the cut flowers. Postharvest longevity of the florists' green varies depending on the species. Senescence of plant organs is controlled by the hormones. Especially the cytokinins and some gibberellins delay the catalytic processes such as chlorophyll loss and protein degradation. In case of leaves detached from Hosta plantaginea plant, 24 hour conditioning in benzyladenine (BA 0.1 mmol · dm⁻³) delayed degradation of the above compounds. Similar effects were observed in detached leaves of Zantedeschia aethiopica treated with gibberellic acid (GA3 0.25 mmol · dm⁻³). In contrary to cytokinins and gibberellins, the ethylene hastens senescence in detached leaves and shoots. Such an effect was observed in Zantedeschia, Paeonia lactiflora and Molucella which wilted and yellowed earlier after treatment with ethylene.