Effect of preservative solutions on postharvest of Eustoma Grandiflorum floral stems during refrigerated storage

Abstract

Preservative solutions contribute to flowers post-harvest quality and longevity, having different effects according to the species, cultivar, cold storage period and the solution composition. This work aimed to determine the preservative solution more effective on opening flower and longevity on flower cut stems of E. grandiflorum, submitted to two cold storage periods. The experiment was arranged in a 2x4x10 factorial, with two storage periods, five and ten days; four preservative solutions, water (100%); sodium hypochlorite (25 ml L-1) + sucrose (10%); aluminum sulfate (250 mg L-1) + sucrose (10%); and silver nitrate (50 mg L-1) + sucrose (10%); and ten evaluation dates. Cut stems from the cultivar ‘White Excalibur’ were placed taken to cold storage for 5 and 10 days at 5°C and 78% of relative humidity. After cold storage, the stems were distributed to glass pots containing different preservative solutions. Every two days, visual evaluations were performed, verifying the opening flower and longevity. An illustrative scale were used to assess the opening of flowers buds, with grades ranging from 1 to 5. For the longevity, the number of days that flowers remained viable in the preservative solutions until the disposal was considered. The cold storage periods do not affect opening flower and longevity of ‘White Excalibur’ floral stems. Silver nitrate + sucrose and aluminum sulfate + sucrose were the preservative solutions that provides better post-harvest quality and longevity, with higher opening flowers and extended viability.