Gholamhasan Movahed; Nima Ahmadi; Ahmad Moieni
Abstract
In order to evaluate the responses of two ecotypes of Damask rose (Rosa damascena) to exogenous ethylene, an experiment was conducted based on a completely randomized design (CRD) at the laboratory of Postharvest Physiology, Tarbiat Modares University, Tehran, Iran. Damsk rose cut stems containg flower ...
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In order to evaluate the responses of two ecotypes of Damask rose (Rosa damascena) to exogenous ethylene, an experiment was conducted based on a completely randomized design (CRD) at the laboratory of Postharvest Physiology, Tarbiat Modares University, Tehran, Iran. Damsk rose cut stems containg flower buds and/or open flowers, single buds, or multiple flowers were exposed to exogenous ethylene for 24 h. Plant organs were placed into hearmatically seald glass chambers, where ethylen was injected, to achieve 0, 1, 2, 3, and 4 µl/l concentrations. Biocehmival characteristics, enzyme activities and morphological characteristics including flower life, contents of anthocyanin, flavonoide, and proline were determind in Kashan and Azaran ecotypes of Damask rose. The lowest psotharvest life was observed at 3 and 4 μl concentration of ethylene and the highest abscission was observed in Azaran ecotypes at a concentration of 4 μl/l of ethylene after four days. Anthocyanin and proline content and catalase activity reduced in both ecotypes studied. For both ecotypes, the lowest content of anthocyanin, proline and the lowest catalase activity (48/77 ΔA 240/mg protein) were observed in those treated with ethylene at 4 µl/l. The highest malondialdehyde (3.63 µmol/g petal fresh weight) was found in Azaran ecotype flowers treated with 4 µl/l ethylene concentration. Decrease of total protein in Kashan flowers (0.32 mg/g fresh petal) was much less than that in Azaran flowers (0.2 mg/g fresh petal). Based on these results, Kashan could be recommended as a tolerant ecotype to be used in breeding programs.