International Society for Horticultural Science (ISHS), Acta Horticulturae, 847, p. 279-286
DOI: 10.17660/actahortic.2009.847.37
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Water status parameters of cut roses that determine bent-neck susceptibility and vase life were examined using cold neutron radiography and tomography (CNR, CNT) with D2O tracer at CONRAD, Helmholtz Center Berlin for Materials and Energy (former HMI) in Berlin, Germany. Also, structural and functional differences of the conductive tissue in bent neck-susceptible and resistant roses were evaluated using synchrotron x-ray tomography at BAM-line, BESSY (Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung) in Berlin, Germany. The Rosa hybrida L. cultivars 'Akito' and 'Red Giant', respectively, which largely differ in their vase life and bent-neck resistances were used for the experiments. Cut rose samples were placed in a crystal glass tube with their stems immersed in pure water. CNR and CNT with D2O tracer was conducted to investigate water uptake before stressing well-watered plants. Then samples were drought-stressed by removing vase water for 4 or 6 h. After this treatment, water uptake by the samples was investigated by CNR and CNT with D2O tracer again. The obtained statistics in CNR and CNT of the rose stem was sufficient for a quantitative analysis of the data. As indicated by CNR, water flow velocity was different in stems of 'Red Giant' and 'Akito'. In this way it was proved that the D 2O tracer method was applicable to observe xylem blockage in rose stems. The high resolution of the synchrotron tomographic images allowed the investigation of plant tissues micro structures. As a conclusion, the combination of CNR, CNT with D2O tracer and synchrotron tomography, are highly applicable to non-destructively and three dimensionally study the water movement in rose peduncles for the investigation of the bent neck syndrome and stem water transport in general.