Water quality effects on postharvest performance of cut calla, hydrangea, and snapdragon

摘要

Effects of water quality on water uptake, change in fresh weight, vase solution pH and electrical conductivity (EC) change, termination symptoms, and longevity of cut 'Nicole Yellow' calla (Zantedeschia L), 'White Extra' hydrangea [Hydrangea macrophylla (Thunb.) Ser.], and 'Admiral Pink' snapdragon (Antirrhinum majus L) were studied. Calla was tolerant of high water pH (8.1); vase life varied only from 9.2 d for acidic solutions (pH 3.2) to 10.1 d for solutions with intermediate pH (6.3). Calla had the longest vase life at an EC of 0.75 dS m(-1), whereas addition of floral preservative (Floralife Professional, Floralife, Walterboro, SC at 10 ml L-1) was ineffective. Low solution pH (2.9-3.3), increasing EC (up to 2.5 dS m(-1)), and use of floral preservative increased vase life of hydrangea. Increasing EC increased vase life of hydrangea from a low of 7.3 d to a high of 15.4 d at 2.5 dS m(-1), when floral preservative was used and from a low of 3.5 d to a high of 5.7 d at 4.0 dS m(-1) in distilled water. Vase solution pH of snapdragon had no significant effect on vase life or water uptake. Increasing EC increased vase life to a maximum of 14.8 d at 2.0 dS m(-1) with preservative and to 9.7 d at 3.0 dS m(-1) without preservative. Each species had differing responses to varying pH and EC levels; however, solution pH should be low, as high pH solutions either had no effect or reduced vase life, such as with hydrangea. EC of vase water for hydrangea and snapdragon should be approximately 2.0-2.5 dS m(-1), when preservatives are used and 3.0-4.0 dS m(-1) without, which is higher than most recommendations. Addition of preservative to vase solutions extended vase life of hydrangea and snapdragon, but did not affect calla