Water Relations of Flowering Stem, Microbial Activity of Preservative Solution and Postharvest Quality of Alstroemeria Cut Flower under Peppermint's Essential Oil and Sucrose Treatments

Postharvest improvement of water relations and water uptake of cut flowers and control of microbial contamination of preservative solutions is one of the most important strategies in maintaining postharvest quality and prolonging of cut flowers vase life; especially for leafy flowering stems such as alstroemeria. This experiment was conducted to evaluate the effects of different peppermint’s essential oil concentrations (0, 300, 600 and 900 ppm) along with sucrose levels (0, 3 and 6%) in a factorial experiment based on the completely randomized design with three replications. Water relations, cell membrane integrity, leaf yellowing disorder and bacterial contaminations of preservative solution of alstroemeria cut flower were evaluated under different treatments. Based on the results, application of essential oil (600 ppm) and sucrose (6%) significantly increased water uptake, cell membrane integrity and photosynthetic pigments, and decreased leaf yellowing disorder and bacterial pollutions, leading, consequently, to higher vase life (14 days) relative to the control cut flowers. It appears that application of peppermint’s essential oil (due to anti bacterial compounds such as menthone and menthol) and sucrose (due to food supply and cell membrane maintenance) could be recommended for addition to the preservative solutions of alstroemeria cut flowers.