Effect of Antioxidant Compounds Arginine, Sodium Nitroprusside, Putrescine and Proline on Vase-Life, Electrolyte Leakage and Activity of Some Narcissus tazetta L. cv.  Shahla Double Enzymes

Narcissus (Narcissus tazetta L.) is one of the cut flowers having short vase-life. A completely randomized design experiment with 3 replications was carried out to assess the effect of antioxidant compounds on some qualitative and quantitative characteristics of this flower. Arginine (Arg), putrescine (Put), proline and sodium nitroprusside (SNP) were used at 1, 5 and 10 μM along with control treatment (distilled water). The highest vase-life was obtained with 1 μM SNP and 5 μM Put which increased vase-life for 3 days compared with control. The lowest electrolyte leakage was obtained with 1 μM SNP and 5 μM Put which reduced electrolyte leakage by 45% and 51%, respectively in comparison with control. The results also, indicated that vase-life was increased with SNP (1 μM), Put (1 and 5 μM) and proline (1 and 5 μM) compared to control. This increase in vase-life was accompanied with significant increase in the activity of antioxidant enzymes and PAL, while polyphenol oxidase (PPO) activity was significantly decreased. Accordingly, it appears that the applied compounds reduced free oxygen radical, preserved cell membrane integrity, increased phenolic compound synthesis and reduced PPO activity which ultimately resulted in higher quality of narcissus cut flowers.