Effects of Active and Passive Modified Atmosphere Packaging on the Vase Life and Quality of Narcissus (Narcissus tazetta L.) ‘Shahla’ Cut Flowers
, and | Dec 11, 2023
Published Online: Dec 11, 2023
Page range: 45 - 54
Received: Jun 01, 2023
Accepted: Sep 01, 2023
DOI: https://doi.org/10.2478/johr-2023-0028
Keywords
© 2023 Farid Moradinezhad et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
According to Ichimura and Goto (2002) and Hunter et al. (2004), the most important factors determining vase life are the level of internal ethylene production and water uptake. Ethylene has been shown to play a major role in shortening the postharvest life of cut flowers (Nowak & Rudnicki 1979) and
The maintenance of the market value of cut flowers, one of the most profitable products of the flower industry, depends on their quality and freshness at harvest time (Arumta et al. 2019; Darras 2021). The preservation of the quality and freshness of flowers affects their market value (Naveena & Thamaraiselvi 2020). The metabolic activity that accelerates the senescence of flowers begins as soon as they are cut from the mother plant. For this reason, the way to preserve the quality and freshness of cut flowers is to delay or suppress those related processes (Byczynski 2008; Faust & Dole 2021). Kazaz (2015) states that about 25% of cut flower trade losses are due to improper management.
Packaging material significantly affected the quality and vase life of
In this research,
The cut flowers were divided into six groups and then treated with different gas compositions (Table 1). Cut flowers are sensitive to water loss during transportation (especially for local markets). Therefore, cut flowers were transported in sealed packages. These conditions create a passive modified atmosphere for cut flowers. For this reason, in the present experiment, we decided to introduce passive-MAP (MAP1) as a control to compare with other treatments.
Treatments with gas compositions applied to cut flowers of
| Treatment | Explanation |
|---|---|
| MAP1 | passive-MAP (0.03% CO2 and 21% O2) |
| MAP2 | vacuum packaging (VP) (0.0% CO2 and 1% O2) |
| MAP3 | high carbon dioxide + air oxygen (40% CO2 and 21% O2) |
| MAP4 | high carbon dioxide + low oxygen (20% CO2 and 10% O2) |
| MAP5 | high carbon dioxide + high oxygen (40% CO2 and 40% O2) |
| MAP6 | air carbon dioxide + high oxygen (0.03% CO2 and 40% O2) |
The air inside the polyethylene bags, 20 × 30 cm low-density polyethylene (LDPE), 0.06 mm thickness, was removed using a vacuum pump, and then the bags were sealed. Twenty-one cut flowers and three replications were considered for each treatment. The bags were sealed after injection of the determined gaseous compounds (active-MAP) and placed in a cool room for six days at 2 ± 1 °C and 85 ± 5% relative humidity. After that, the flowers were unpacked and placed in polyethylene (PE) containers with 2000 ml volume (20 × 15 cm) with a holding solution (500 ml of 2% sucrose solution). Aluminum foil was used on the mouth of the container to prevent the solution from evaporating. The flowers were then kept at room temperature (20 °C) for 16 days.
Vase life was determined by the days from placing the flowers in the holding solution to the day when 50% of the petals faded, according to Alipur et al. (2013).
The relative fresh weight (RFW) percentage (% of initial fresh weight) of narcissus cut flowers was measured daily until the eighth day by a digital scale with an accuracy of 0.001 g. It was obtained by dividing by the initial weight and multiplying by 100, according to Sairam et al. (2002).
Weights of vase solutions without the cut flowers were recorded daily during the vase life evaluation period and expressed in (g per day per stem). The study was performed daily until the eighth day of the experiment.
The Leibe and Schiele (2003) method was used to measure the apparent quality of the narcissus cut flower. In this method, fresh flowers of maximum quality received 100 points, and flowers of lower quality received fewer points. The details of the cut flower evaluation system are as follows: flower shape (maximum 30 points), flower position relative to stem (maximum 25 points), flower color (maximum 25 points), and the freshness of the stem or the stiffness of the stem (maximum 20 points). The apparent quality of the flowers was checked every two days and continued until the flowers received a minimum score. The remaining traits were assessed every two days until the end of the period (when the flowers dried completely).
The cut flowers were stored until completely dry. The day when all the flowers on the branches completely withered was considered total life (Faragher et al. 1984).
Total sugars in flowers were measured using anthrone reagent in 0, 2, 4, 6, 8, 10, and 12 days. 0.1 g of dried flower was weighed, and 2.5 ml of 80% ethanol was added to it at 90 °C and mixed with a vortex for 60 minutes. The resulting mixture was passed through filter paper, and the alcohol was evaporated. Then, 2.5 ml of distilled water was added and 200 μl of each sample was poured into the test tube, and 5 ml of anthrone reagent was added to it. After stirring, the test tubes were placed in a hot water bath of 90 °C for 17 minutes. The samples were read at a wavelength of 623 nm using a spectrophotometer (Model Unico 2100, China). The data were expressed in mg glucose per g of dry weight (DW).
The experiment was conducted using a completely randomized design with six treatments. Three replications were considered for each treatment, and seven flowering stems were prepared for each replication. Data were analyzed using ANOVA. All analyses were performed with the GenStat program (Discovery edition, version 9.2, 2009, VSN International, UK). The least significant difference (LSD) test at the level of 5% (P ≤ 0.05) was used to identify the significant differences between the means.
According to the results in Figure 1, the different MAP treatments significantly affected the vase life of the narcissus cut flowers. The most extended vase life was related to cut flowers stored at 20% CO2 and 10% O2 (15.8 days) (MAP4). Also, in MAP3, MAP5, and MAP6 treatments, an increase in vase life was observed compared to the MAP1 and MAP2 treatments. The passive-MAP (MAP1) and vacuum (MAP2) did not differ significantly and showed the lowest vase life, 9.2 and 9.9 days, respectively. MAP4 treatment significantly increased the vase life by approximately 71% compared to passive-MAP.
Figure 1.
The vase life (A) and total life (B) of narcissus cut flowers under different MAP pretreatments for 6 days of storage at 2 °C and then at room temperature (20 °C)
Symbols with the same letter are not significantly different (P ≤ 0.01, LSD test); Error bars represent the error deviation; MAP1 – passive-MAP, MAP2 – vacuum, MAP3 – 40% CO2 + 21% O2, MAP4 – 20% CO2 + 10% O2, MAP5 – 40% CO2 + 40% O2, and MAP6 – 0.03% CO2 + 40% O2
The effects of the different MAP treatments on the RFW of the narcissus cut flower during the vase life are shown in Figure 2. The increase in fresh weight occurred until the third day of the vase life in all treatments, excluding MAP4, where increasing was observed until the sixth day. In addition, the fresh weight of all treatments stayed within their initial weights during the eight days of study. The highest fresh weight was obtained in MAP4 treatment at each term. Generally, all treatments had a higher fresh weight than the passive-MAP (MAP1) and vacuum (MAP2). During the experiment, MAP2 and MAP6 treatments did not show any significant difference with each other. However, on day 8, the lowest RFW of flowers was obtained from MAP1 treatment, followed by MAP2, MAP6, and MAP3. There was no significant difference between MAP2, MAP6, and MAP3 treatments. The highest fresh flower weight was obtained from MAP4 treatment, followed by MAP5 treatment.
Figure 2.
Relative fresh weight of narcissus cut flowers under different MAP pretreatments for 6 days of storage at 2 °C and then at room temperature (20 °C)
* and ** indicate significance at the 0.05 and 0.01 levels, respectively; Error bars represent the error deviation; MAP1 – passive-MAP, MAP2 – vacuum, MAP3 – 40% CO2 + 21% O2, MAP4 – 20% CO2 + 10% O2, MAP5 – 40% CO2 + 40% O2, and MAP6 – 0.03% CO2 + 40% O2
Results in Figure 3 show the significant differences in amounts of water uptake by the narcissus cut flowers, dependent on the treatment. During the initial three days, the water uptake increased in all treatments, with the highest in MAP4 followed by MAP5 treatment and the lowest in MAP1 treatment. Moreover, water uptake was higher in all treatments than in MAP1 until the final day of the experiment. In all treatments, the water uptake pattern was similar during eight days, but the amount of water depended on the treatment. The evaluations showed that at the end of the experiment (day 8), the lowest amount of water absorption was related to MAP1 treatment. However, no significant difference was observed between MAP1 and MAP2 treatment. The highest amount of water absorption was obtained in cut flowers of narcissus in MAP4 treatment, followed by MAP5 treatment. There was no significant difference in water uptake between MAP5 and MAP3 treatments.
Figure 3.
Water uptake of narcissus cut flowers under different MAP pretreatments for 6 days of storage at 2 °C and then at room temperature (20 °C)
* and ** indicate significance at the 0.05 and 0.01 levels, respectively; Error bars represent the error deviation; MAP1 – passive-MAP, MAP2 – vacuum, MAP3 – 40% CO2 + 21% O2, MAP4 – 20% CO2 + 10% O2, MAP5 – 40% CO2 + 40% O2, and MAP6 – 0.03% CO2 + 40% O2
There was a clear trend in the appearance quality (%) mainly based on petals drying with the storage time (Fig. 4). The quality was the highest and delayed slower in MAP4 treatment all the time compared to the other treatments. The results showed that the petals in MAP1, MAP2, and MAP6 treatments begun to fade on the experiment's third day. In the MAP4 treatment, the quality was delayed gradually from day 6 of the experiment, whereas in the other treatments, it was delayed from the fourth day. The quality 0 in this treatment was on day 22 in MAP4, on day 16 in MAP3 and MAP5, on day 17 in MAP6, and on day 14 in MAP1 and MAP2.
Figure 4.
Appearance quality of narcissus cut flowers under different MAP pretreatments for 6 days of storage at 2 °C and then at room temperature (20 °C)
* and ** indicate significance at the 0.05 and 0.01 levels, respectively; MAP1 – passive-MAP, MAP2 – vacuum, MAP3 – 40% CO2 + 21% O2, MAP4 – 20% CO2 + 10% O2, MAP5 – 40% CO2 + 40% O2, and MAP6 – 0.03% CO2 + 40% O2
In all MAP treatments, the amount of total sugars in cut narcissus initially increased and then decreased (Fig. 5). In MAP1 and MAP2 the values increased until the 6th day and in the MAP1, MAP2, MAP5, and MAP6 treatments until the 8th day. Only in MAP4, soluble sugars increased steadily until the 12th day. Then, the sugar content decreased in MAP1 and MAP2 to the initial level, and the remaining ones to a higher level.
Figure 5.
Total sugar content in narcissus cut flowers under different MAP pretreatments during 12 days of storage at room temperature (20 °C)
Error bars represent the error deviation; MAP1 – passive-MAP, MAP2 – vacuum, MAP3 – 40% CO2 + 21% O2, MAP4 – 20% CO2 + 10% O2, MAP5 – 40% CO2 + 40% O2, and MAP6 – 0.03% CO2 + 40% O2
Vase life refers to how long cut flowers remain attractive and aesthetically valuable. It is a crucial consideration for the flower industry in identifying plant species with a long vase life. The results of the present study clearly showed an increase in the vase life of
The increase in the weight of cut flowers is related to the amount of water absorption through the vessels. Insufficient water uptake due to xylem occlusion is one of the main reasons for the poor performance of cut flowers during the vase life. The leading causes of xylem occlusion are microbial growth, deposition of materials such as gums and mucilage in the lumen of xylem vessels, formation of tyloses, and the presence of air emboli in the vascular system (Panja et al. 2018). However, in this experiment, we tried to reduce stem embolism and other vascular obstructions by cutting the end of the stem. Halevy and Mayak (1979) stated that when the flowers are placed in the vase solution after cutting, their fresh weight generally increases initially and then decreases, which was confirmed in our experiment. The weight of cut narcissus flowers and water uptake were the highest after pretreatment with 20% CO2 and 10% O2 compared to other air compositions. High carbon dioxide may reduce the microorganism's population, leading to more water uptake and increased flower weight. Poonsri (2021b) reported that treatment of
The most important factor in the marketing of flowers is their appearance quality. It has been proven that the change in leaf color from green to yellow is a sign of senescence in cut flowers (Halevy & Mayak 1979), caused by the decomposition of chlorophyll. However, in narcissi, senescence is characterized by the drying of the petals. Treatment with high CO2 and low O2 showed less loss of visual quality. High carbon dioxide treatment may have delayed the senescence and drying of the petals by reducing the ethylene biosynthesis. Zeltzer et al. (2001) stated that the modified atmosphere maintains the appearance quality of various cut flowers, such as
The vase life is expressed from placing the flowers in holding solution until the loss of the decorative value of each flower in the inflorescence as a result of wilting or drying and bending of the petals. Narcissus is a potent source of fragrance, highly valued in the industry (Li et al. 2019).
Ethylene is a plant hormone that affects many physiological plant processes (especially ripening and senescence). Essential enzymes in the path of ethylene synthesis are 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase, which catalyze the reaction from S-adenosylmethionine to ACC and from ACC to ethylene, respectively (Murr & Yang 1975). It has been shown that the inhibition of ethylene production by carbon dioxide is due to the occupation of ethylene binding sites (ethylene binding protein – EBP) (Ahammed & Li 2022). Interestingly, Rothan and Nicolas (1994) showed that CO2 could either stimulate or inhibit ethylene synthesis in tissue, depending on the internal ACC level. However, most studies indicate inhibition of ethylene biosynthesis by high carbon dioxide (Hosseini & Moradinezhad 2018; Moradinezhad et al. 2018).
In the current study, the application of high CO2 and low O2 treatment delayed the senescence and drying of the petals. In remaining treatments, the senescence process of cut flowers was faster. However, we observed that in the case of high CO2 treatment (40% CO2 and 20% O2), the petals dried earlier. Therefore, to suppress the effect of ethylene, it is necessary to find the optimal ratio of CO2 to O2 to extend the vase life of cut narcissus flowers. A study on
Carbohydrates improve water balance and are used as a substrate for respiration and building plant cell walls. Carbohydrate deficiency directly affects the life of a flower. The last stage of flower development is associated with a decrease in the carbohydrate content in the petals, so placing the flowers in solutions containing carbohydrates can extend flowering vase life (Pun & Ichimura 2003). Sucrose helps in the plants’ water balance, and this role has been attributed to the closing of stomata and the reduction of water levels. Soluble solids, especially sugars, are one of the most important and influential factors in determining the life of cut flowers. Hydrolysis of cellular compounds is a sign of the senescence process in response to the lack of sugars used in respiration (Jacobi et al. 2001). Sucrose is the primary source of energy for biochemical and physiological processes after the flower shoots are separated from the mother plant. Sucrose also increases the mechanical strength of stems, stimulating the thickening of cell walls and lignification of vascular tissues. It neutralizes the effect of abscisic acid, which stimulates senescence (Kühn & Grof 2010). In this experiment, the amount of sugars in all treatments increased during the early stages of the experiment (first six days in holding solution), which indicates the uptake of sucrose by flowers. However, with time and probably blockage of the vessels, the freshness of the flowers decreased, and the amount of sucrose absorption and sugar level decreased. Interestingly, only in the case of the MAP4 treatment (20% CO2, 10% O2) an increasing trend in sugar content was recorded until the 12th day of the experiment. Our study confirmed the results of Poonsri (2021b), who reported that the use of high carbon dioxide and low oxygen content preserved sugars and reduced protein degradation in cut orchid flower petals.
Modified atmosphere treatment significantly affected the quality parameters of narcissus cut flowers of