Cut roses (Rosa hybrida L.) have been classified as ethylene-sensitive, but the nature of the ethylene sensitivity changes in these flowers has not been well characterized. Therefore, in this work, ethylene-insensitive cut roses consisting etr1-1 gene were evaluated. Cut roses prepared from an isolated greenhouse at commercial stage, after transferring to the laboratory, were compared regarding the content of antioxidant enzymes by ethylene treatment (0, 0.5 and 1 μl l-1). Evaluations were carried out in wild type and transgenic line in bud and half-open stages. The research was performed in completely randomized factorial design by four replicates. After measuring and applying the statistical differences at the P ≤ 0.05 level via SAS software was done. The results showed that ethylene significantly increased superoxide dismutase, catalase and guaiacol peroxidase activities in bud and half-open stages in wild type and transgenic line. Maximum antioxidant enzymes activity was observed in wild type roses in bud and half-open stages treated by 1 μl l-1 ethylene which had a significant difference in comparison with the same stage in transgenic line. According to the increasing trend of these enzymes activities in wild type and transgenic lines with higher concentrations of ethylene, it seems that, ethylene by inducing senescence oxidative damage could accelerate flower senescence. Therefore, genetic manipulation of ethylene receptor genes of ethylene-sensitive flowers as well as roses could decrease oxidatve stress during senescence and considerably improved longevity.
