Termination of vase life for cut flowers is characterized by wilting associated with an imbalance developing between water uptake through xylem conduits in stems and water loss through stomata and other structures on leaves and other organs. To better understand the onset of adverse postharvest water relations, cut flower researchers seek to acquire data on rates of water uptake and water loss. These indices are usually monitored by weighing stems and vases daily or thereabout with a single analytical balance (He et al., 2006; Liu et al., 2009; Macnish et al., 2008). This approach is appropriate to provide an accurate assessment of general trends in water uptake and water loss of cut flowers over time. However, it is costly in terms of labor and is not appropriate for precise temporal measurement of water uptake and water loss by cut flower stems.
Thus, there is need for an apparatus that can routinely and dynamically distinguish small environment and/or treatment effects to realize precise monitoring of cut flower water uptake and water loss. To measure water uptake rates of individual cut rose stems, Carpenter and Rasmussen (1973) designed a potometer with a side arm calibrated to 0.01 mL. Although useful, it was not automatic and not highly precise. Accordingly, a continuous automatic apparatus (CAA) was devised to measure water uptake, water loss, and fresh weight of cut flowers. Its preliminary application was reported by Lü et al. (2009).
To evaluate the use of the CAA in investigating postharvest water relations of cut flowers, a series of experiments reported here were conducted. They ascertained the efficacy of the CAA to accurately measure water uptake rate and water loss rate for individual cut rose (Rosa hybrida cv. Movie Star) and lily (Lilium hybrida cv. Yellow Overlord) stems under alternating light and dark regimes during their vase period.
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Liu, J., He, S., Zhang, Z., Cao, J., Lv, P., He, S., Cheng, G. & Joyce, D.C. 2009 Nano-silver pulse treatments inhibit stem-end bacteria on cut gerbera cv. Ruikou flowers Postharvest Biol. Technol. 54 59 62
Lü, P., He, S., Liu, J., Cao, J. & Joyce, D.C. 2009 A new apparatus for continuous automatic measurement of water relations in stems of cut flowers 314 315 Intl. Conf. Plant Vascular Biol Agr. 2009 Abst. Book, Beibei, China
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