International Research Journal of Applied and Basic Sciences 2012 Available online at www.irjabs.com ISSN 2251-838X / Vol, 3 (10): 2052-2056 Science Explorer Publications The effects of Acetyl CoA as a chemical preservative on postharvest life of gerbera cut flowers Shima Seyedi 1*, Ali Reza Ladan Moghadam 1, Vahid Abdossi 2 1. Department of agriculture, garmsar branch, islamic azad university, Garmsar, 2. Department of Agriculture, Science and Research Branch, Islamic Azad University, Tehran, Iran *corresponding author email: shirin.mahmood@yahoo.com ABETRACT: Production, increased quality and longevity of cut flowers like gerbera are of universal and economical importance. Various chemicals especially plant growth regulators are suggested as preservatives in vase solution which could influence postharvest life of different cut flowers. With the purpose of obtaining better new chemical preservatives, the present study was carried out in completely randomized design to investigate the possible effects of various concentrations of Acetyl CoA, a vital primary metabolite, on the biochemical changes of gerbera cut flowers during the postharvest life. Acetyl CoA was used in six different concentrations including 0, 5, 10, 20, 40 and 80mgL -1. The cut flowers were grouped in six various treatment groups including control (C), A5, A10, A20, A40 and A80. The application of different concentrations of Acetyl CoA resulted in stimulated gibberellic acid contents and activity of antioxidant enzymes (Catalase and superoxide dismutase) as well as alleviated membrane lipid peroxidation and degradation rates of anthocyanin during postharvest life of gerbera cut flowers. The obtained results from present research indicated that the application of Acetyl CoA led to biochemical changes caused declined senescence probably via enhanced antioxidant system and promoted longevity of gerbera cut flowers. Acetyl CoA-biochemical induced changes in treated cut flowers could result from involvement of acetyl coenzyme A in different metabolic pathways like kerebs cycle and synthesis of isopentenyl pyrophosphate, a critical precursor of variety of terpenoids like GA. keywords:acetyl CoA, Cut flower, Gerbera jamesonii, Ornamental, Postharvest abbreviation:cat- catalase; GA- Gibberellic acid; MDA- malondialdehyde; SOD- superoxide dismutase INTRODUCTION The postharvest life of cut flowers could be influenced by the application of different chemical preservatives such as various plant growth regulators in the vase solution (Prashanth et al., 2010). The most recommended chemicals are benzyladenin (BA) and gibberellic acid (GA) Danaee et al., 2011). However the effects of their precursors on post harvest life of cut flowers have not been investigated so far. Acetyl CoA is a vital primary metabolite involved in different aspects of metabolism like respiration and lipid metabolism. Three molecules of acetyl CoA is required for producing of mevalonate which is converted into isopentenyl pyrophosphate, precursor of variety of isopernoids and terpen derived compounds (Habibi et al., 2011). Thus acetyl CoA is implicated in metabolism of terpenoids and terpen-derived substances. Gerbera is a valuable and important ornamental plant. With the purpose of finding better new chemical as a preservative in vase solution, the present study was carried out to investigate the possible effects of acetyl CoA application on the vase life of gerbera cut flowers. MATERIAL AND METHODS Cut gerbera flowers, Gerbera jamesonii cv. Rosalya, were obtained from commercial growers. Experiments were performed in a postharvest room (22 ± 1 ºC, 60 ± 5% relative humidity and 12 h photoperiods). 50-centimeter long flowers were cut, weighted and placed in 500 ml containers with 3% sucrose and six different concentrations (0, 5, 10, 20, 40 and 80 mgl -1 ) of acetyl CoA solutions. Cut flowers were grouped in six different treatment groups with
three replications and five flowers in each ones including Control (C), A5, A10, A20, A40 and A80. Flowers in solution containing 3% sucrose in distilled water were used as control samples. Superoxide dismutase activity (SOD) was determined as previously described by Misra et al., (1972). Gibberellic acid (GA) concentration was measured as previously described by Shengjie et al., (2008). Lipid peroxidation rate was estimated by the content of total thiobarbituric acid reactive substances (TBARS) expressed as equivalents of malondialdehyde (MDA). Flower pigmentation was quantified by measuring the amount of anthocyanins in fresh ray florets as described previously by Meng and Wang (2004). Acidic methanol (1% HCl, v/v) was used as an extraction solvent. Anthocyanin concentrations of petals were calculated according to the formula given below. Vase lives of cut flowers were recorded based on their senescence. Statistical procedure Analysis of variance was performed on all data sets using SPSS software. Duncan test with probability of 0.05 was used to assess any significant differences between treatments. RESULTS AND DISCUSSION The application of acetyl CoA had enhancing effects on gibberellic acid contents as it was shown in figure 1. The significantly induced superoxid dismutase and catalase activities during the postharvest life were found in Acetyl CoA-treated cut flowers with the highest amount observed in A10 and A20 treatment groups (Figure 2, 3). Figure 1. The effects of different concentrations of acetyl CoA on changes in GA contents of gerbera cut flowers during postharvest life stages. The vertical bars indicate standard error (SE) of three replications.!"#$%$&$' Figure 2. The effects of different concentrations of acetyl CoA on changes in superoxid dismutase activity of petal tissues during postharvest life stages. The vertical bars indicate standard error (SE) of three replications.
#$%$&$' Figure 3. The effects of different concentrations of Acetyl CoA on changes in catalase activity in petal tissues during postharvest life stages. The vertical bars indicate standard error (SE) of three replications. " ) Figure 4. The effects of different concentrations of acetyl CoA on malon dialdehyde contents in petal tissues of gerbera cut flowers during postharvest life stages. The vertical bars indicate standard error (SE) of three replications. (
*#$ ) Figure 5. The effects of different concentrations of acetyl CoA on anthocyanin contents in petal tissues of gerbera cut flowers during postharvest life stages. The vertical bars indicate standard error (SE) of three replications. +%$,,# # # Figure 6. The effects of different concentrations of acetyl Coal on longevity of gerbera cut flowers. The vertical bars indicate standard error (SE) of three replications. Their activities gradually decreased in cut flowers which the reduction rates were significantly much fewer in acetyl CoA applied ones. During posatharvest life, gradually increasing membrane peroxidation were observed in all treament groups. however compared to the control samples, the significantly declined membrane peroxidations were recorded in acetyl CoA-treated cut flowers (Figure 4). Decreasing rates of anthocyanin content during postharvest life were significantly declined by the applied acetyl CoA treatments (Figure 5). The obtained results from present study indicated that the application of acetyl CoA had enhancing effects on GA contents and antioxidant enzymes (SOD and CAT) and alleviating influence on membrane peroxidation rates and anthocyanin degradation levels during the postharvest life stages of gerbera cut flowers. Acetyl CoA is implicated in different aspect of metabolism including carbohydrates, lipids and terpenoids. Thus it seems that physiological changes
induced by the application of acetyl CoA resulted from increased terpenoids especially GA. In addition, acetyl CoA application, as a component of kerebs cycle, could change the status of ATP and reduced coenzymes in cells. GAstimulated antioxidant enzymes resulted in decreased accumulation of active oxygen species and declined lipid peroxidation (Qing Zhu et al. 2011). Senescence of cut flowers is correlated with the carbohydrate content (van ). Gibberellins could form sink via induction of especial physiological process (Iqbal et al. 2011). In total, the application of acetyl CoA as a preservative in vase solution led to promoted vase life of gerbera cut flowers as it was shown in figure 6. According to the obtained results from this research it seems that the application of acetyl CoA could lead to promoted longevity of gerbera cut flowers via induction of especial physiological changes resulted in alleviated senescence. Therefore it might be used as a preservative in vase solution. ACKNOWLEDGEMENTS This study is supported by the Islamic Azad University, Garmsar branch. Authors would like to thank Dr. Z. Oraghi Ardebili for her warming helps. REFRENCES Danaee E, Mostofi Y, Moradi P. 2011. Effect of GA3 and BA on postharvest quality and vase life of gerbera (Gerbera jamesonii. cv. Good Timing) cut flowers. Hortic Environ Biotechnol. 52(2):140-144. Emongor VE. 2004. Effect of gibberellic acid on postharvest quality and vase life of gerbera cut flowers (Gerbera jamesonii). J Agron. 3:191-195. Habibi A, Heidari G, Sohrabi Y, Badakhshan H, Mohammadi K. 2011. Influence of bio, organic and chemical fertilizers on medicinal pumpkin traits. J Med Plants Res. 5(23): 5590-5597. Iqbal N, Nazar R, Khan MIR, Masood A, Khan NA. 2011. Role of gibberellins in regulation of source-sink relations under optimal and limiting environmental conditions. Curr Sci. 100 (7): 998-1007. Meng X, Wang X. 2004. Relation of flower development and anthocyanin accumulation in Gerbera hybrida. J Hort Sci Biotech. 79:131-137. Misra HP, Fridovich I.1972. The role of superoxide anion in the autoxidation of epinephrine and a simple assay for superoxide dismutase. J Biol Chem. 247: 3170-3175. Moreno D, Berli FJ, Piccoli PN, Bottini R. 2011. Gibberellins and abscisic acid promote carbon allocation in roots and berries of grapevines. J Plant Growth Regul. 30(2): 220-228. Prashanth P, Chandra Sekhar R, Chandra Sekhar R K. 2010. Influence of floral preservatives on scape bending, biochemical changes and post harvest vase life of cut gerbera (Gerbera Jamesonii bolus ex. Hook.). Asian J Hortic. 5(1): 1-6. Qing Zhu L, Chao Han L, Xian Chang Y, Qing Hua S. 2011. Gibberellin A 3 pretreatment increased antioxidative capacity of cucumber radicles and hypocotyls under suboptimal temperature. Afr J Agric Res. 6(17): 4091-4098. Shengjie H, Jiang Z, Ding M, Guohua LV. 2008. Simultaneous determination of gibberellic acid, indole-3-acetic acid and abscisic acid in Wheat extracts by solid-phase extraction and liquid chromatography-electrospray tandem mass spectrometry. Talanta 76(4): 798-802. Singh A, Kumar J, Kumar P.2008. Effects of plant growth regulators and sucrose on post harvest physiology, membrane stability and vase life of cut spikes of gladiolus. Plant Growth Regul. 55: 221 229. Van Doorn WG. 2004. Is petal senescence due to sugar starvation?. Plant Physiol. 134: 35 42. -