Visible and Near-infrared (Vis/NIR) spectroscopy is widely used to analyze plant physiological state and chemical properties non-destructively and rapidly. Recently, Vis/NIR spectroscopy has been used to analyze and estimate the photosynthesis capacity, water content, and soluble solids content (SSC) in various horticultural crops such as fruits and vegetables. Cut roses are often sensitive to water stress under unfavorable conditions during storage and transportation. Water stress of cut flowers generally leads to premature wilting of leaves and petals, thus decreasing the vase life of cut flowers. In this study, we measured the water content and SSC and evaluated the postharvest quality of cut roses using Vis/NIR spectroscopy to screen the quality of cut rose flowers for promoting exportation. Cut roses underwent either wet transport (WT), dry transport (DT), or dry and sucrose treatment, to identify the characteristics of reflectance wavelengths (RW) closely correlated with water content of cut flowers based on Vis/NIR data. Our results showed that dry treatment reduced the vase life and maintenance of positive water balance (PWB) and initial fresh weight of cut roses. Sucrose treatment exhibited a longer duration of retaining PWB and increased SSC in the petals and leaves of cut rose flowers. WT resulted in cut roses with a longer vase life of 1.4 d, compared to DT. DT treatment also decreased the capacity of the cut flowers to maintain PWB by 0.7 d compared to WT. Our results also showed that the Vis/NIR reflectance of the rose petals in the wavelength range 620-720 nm differed among treatments. In particular, the water balance of cut roses showed a positive correlation with RW735 nm and a negative correlation with RW680/RW(620 720) nm, while the SSC of cut roses was positively correlated with RW680/RW(620 720) nm. These results imply that it is possible to evaluate and screen the postharvest quality of rose flowers based on the water relation of cut flowers using Vis/NIR spectroscopy data.
