Mohammad Reza Asghari; Zahra Azarsharif; Hossein Tajik; Alireza Farrokhzad
Abstract
Introduction: Galbanum, an aromatic oleo-resin gum, is produced from umbelliferous Persian plant species in the genus Ferula with the common Persian name “Barije”, chiefly endemic flora of the mountain ranges of northern Iran. Cuminum cyminum is an edible medicinal plant, which is widely distributed ...
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Introduction: Galbanum, an aromatic oleo-resin gum, is produced from umbelliferous Persian plant species in the genus Ferula with the common Persian name “Barije”, chiefly endemic flora of the mountain ranges of northern Iran. Cuminum cyminum is an edible medicinal plant, which is widely distributed in Iran, Turkey, India, Egypt and Central America countries. Calcium (Ca2+) is a secondary messenger that plays pivotal roles (such as cell wall structure, signaling in fruit ripening and ethylene biosynthesis) in regulating physiological functions in fruits, vegetables and flowers during postharvest life. Sweet cherry is one of the most popular fruits among consumers because of its good taste and abundant nutrients and bioactive components such as phenolic compounds and flavonoids. This fruit is a highly perishable product due to its high respiration rate and rapid softening process at room temperature, which ultimately cause the color changes, weight loss, browning and changes of nutrients and restrict its shelf life. Several studies have demonstrated that the postharvest life of sweet cherries can be extended by different preservation techniques, such as refrigeration, synthetic chemical fungicides, modified atmosphere packaging, osmotic treatments, hypobaric treatments, heat treatments and edible coating. In the last several years, edible coatings have been widely studied for the preservation of fruits and vegetables. Edible coating with semipermeable films might extend the postharvest life of sweet cherry through a reduction of moisture migration, gas exchange, respiration and oxidative reaction rates. Materials and Methods: Healthy fruits, uniform in size, shape, color, and degree of maturity were selected from sweet cherries collected from orchard in Kahriz located in Urmia. Effects of galbanum gum (0, 1, 2 and 3% W/V), cumin essential oil (0, 100 and 200 µl/l) and calcium chloride (0 and 1% W/V) coating on the physiological and quality responses of sweet cherry (Prunus avium Cv. Siah Mashhad) fruit were investigated. The fruits were coated, and stored at 2±1 ºC and 90-95% relative humidity for 30 day and then transferred to 20 ºC for an additional 1 day. The quality of sweet cherries was analyzed at the initial day, 15-day after storage in 2±1 ºC and 30-day after storage in 2±1 ºC+ an additional 1 day in 20 ºC. Different qualitative and physicochemical attributes including pH, total soluble solid, titrable acidity, fruit water content and moisture percentage, proline, malondialdehyde, phenyl alanine amonialyase (PAL) enzyme activity and nutraceutical (total phenol and flavonoid) evaluations were performed. Statistical analysis of data was done by SAS (version 9.4) and mean comparisons were performed using Duncan's multiple range test. Result and Discussion: Significant differences were observed in fruit coated galbanum gum 1% W/V, cumin essential oil 200 µl/l and calcium chloride 1% W/V as compared to the control. The coating applications including gum, cumin essence and calcium chloride resulted in slower rise of pH and TSS, and were effective in maintaining higher titrable acidity, fruit water content, moisture percentage, PAL enzyme activity, total phenol and flavonoid. Coating with 1% W/V galbanum gum combined with 1% W/V calcium chloride resulted in highest increase of PAL enzyme activity and total phenol 15-day after storage, which effectively prevented rapid decline enzyme activity and phenolic compound to the end of storage. The combined coating of galbanum gum 2% W/V with CaCl2 1% W/V or 200 µl/l cumin essential oil significantly maintained total flavonoid 30-day after storage in 2±1 ºC + an additional 1 day in 20ºC; These treatment are not significantly different with galbanum gum 1% W/V with CaCl2 1% W/V or 200 µl/l cumin essential oil. Concomitantly proline content (0.002748 mgr/gr F.W.) was at higher levels and malondialdehyde (0.0320 mmol/gr F.W.) at lower levels in tissues of treated fruit with 1% W/V CaCl2 compared with those of control fruit at the end of storage. Conclusion: Fruit and vegetables are highly perishable, and the causes of postharvest losses can generally be ascribed to physiological deterioration associated with consumption of the internal water and reserve substances. In addition, increasing public concern towards healthy foods has contributed to the promotion of interest in the development of alternative (Safe) methods for controlling postharvest decay and deterioration. These results suggest that galbanum gum, cumin essence and CaCl2 treatments delayed the development of senescence process ‘Siah mashhad’ sweet cherry by delaying the loss of quality parameters, polyphenol substances and maintaining the structural integrity of cell membrane. Application of 1% W/V galbanum gum coating combined with 1% W/V CaCl2 might be enhanced low temperature tolerance by maintaining quality parameters, antioxidant compound and shelf life of sweet cherry fruits.
Naser Abbaspour; Lavin Babaei; Alireza Farrokhzad
Abstract
Introduction: Water stress is considered as a main environmental factor limiting crop growth and yield, including grape in Mediterranean areas.Selection for drought-tolerantvarieties is possible through investigation of their performance under stress conditions. The estimation of physiological characteristics ...
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Introduction: Water stress is considered as a main environmental factor limiting crop growth and yield, including grape in Mediterranean areas.Selection for drought-tolerantvarieties is possible through investigation of their performance under stress conditions. The estimation of physiological characteristics as reliable indices can be used as a tool to select tolerant plants. For this reason, varieties and genotypes of one plant species are usually investigated through physiological characteristics and its relation to drought tolerance. Investigation of the effects of water stress on some growth and physiological characteristics in grape plants has revealed that plant height, number of leaves and nodes, leaf area and the percentage of dry weightdecreased under increasing drought stress. Salicylic Acid is a naturally occurring plant hormone whichinfluences various morphological and physiological functions in plant. It can act as an important signaling molecule and has diverse effects on biotic and abiotic stresses tolerance capacity.
Materials and Methods: In this research, two-yearold grapesplanted in plastic pots containingingredients of humus, soil and sand (1:2:1) were used. The experiment was conducted using a factorial based on randomized complete block design with three factors including irrigation periods (every 5, 10 and 15 days), salicylic acid concentrations (0, 1 and 2 mM) and grape cultivars (Rasheh andBidanesefid) with 3 replications in thegreenhouse of faculty of agricultureinUrmia University. Plant height, stem diameter and leaf area and chlorophyll indicesweremeasuredby usingruler, digital caliper (Model22855 NO: Z), leaf Area Meter (ModelAM200) and SPAD-502 chlorophyll meter (Minolta Crop, Japan),respectively. In order to determine proline content, malondialdehyde (MDA), total protein and total soluble sugars, spectrophotometric methods [51,25,6and28] were utilized,respectively.
Results and Discussion: Based on comparing the averages related to the interaction of various levels of drought and salicylic acid, increasing watering intervals resulted in significant decrease in parameters of plant height, stem diameter, leaf area, leaf number and chlorophyll index,and increase inproline content, malondialdehyde, total protein and total soluble sugars.Furthermore, according to the obtained results, plant height, stem diameter, leaf number, chlorophyll index, accumulation of prolineandtotal protein in grape cv. Rashehwere higher than Bidanesefidone.Drought effected the mitotic division, andelongation and expansion of cells, leading to reduced growth and crop yield. It was concluded that plant height, stem diameter, and leaf area decreased noticeably byincreasing water stress. The reduction in plant height could be attributed to decline in the cell enlargement and higher rate ofleaf senescence in the plant under water stress. The reduction in leaf number under severe water deficit was partially due to leaf senescence. Reduction inthe number of leaves could be a response by plants to minimize the transpiration surface. Sorghum plants have also been reported to have a similarbehaviorthroughwhichthey conserve water by reducing the number of leaves. When exposed to chronic water deficit, they showed an initial decrease in the daily increment of leaf area and eventually a decrease due to accelerated senescence. Dropping of the leaves during severe stress markedly reduces the evaporative surface and allows the plant to conserve water.It is well known that proline contents in leaves of many plants are enhanced by several stresses including drought stress. The efficiency of exogenous SA depends on multiple causes such as the species, developmental stage of the plant, manner of application and concentration of SA.Plant height, stem diameter, leaf number, leaf area, leaf total soluble sugar and chlorophyll index increased by applying 2 mM salicylic acid comparedwith 0 and 1 mM doses. The findings of this study showed that salicylic acid was able to enhance the tolerant capacity of the grape plant to the drought stress. According to theobtained results, Rashehcultivar showed a greater resistance to drought stress. Salicylic acid prohibits auxin and cytokinin loss in plants and thus enhances cell division and plant growth. Salicylic acid maintainsphotosynthetic aspects like chlorophyll content at proper level and thus helps plants to grow and developwell. In this study, the drought stress increased the amount of MDA.MDA and other aldehydes in the dry conditions are the result ofactive oxygen species (ROS) such as super oxide radical, peroxide, hydrogen and radical hydroxide, whichareproduced underoxidative stress conditions. The species of active oxygen leads to lipids' per oxidation as a result of injury or damage to the cellular membrane, especially chloroplast membrane.Salicylic acid increases the activity of antioxidant enzymes such as CAT, POD and SOD which in turn protect plants against ROS generation and lipid peroxidation. Salicylic acid treatment also providesa considerable protection from the enzyme nitrate reductase, thereby maintaining the level of diverse proteins in leaves.Mohammadkhani and Heidari (48) found that the initial increase in total soluble proteins during drought stress was due to the expression of new stress proteins.
