Postharvest physiology
Behzad Kaviani; Mohammad Reza Safarimotlagh; Sara Hataminejad
Abstract
Introduction Chrysanthemum (Chrysanthemum morifolum L.) is one of the most important cut flowers in the world, which currently ranks second in the world after rose in terms of economy and cultivation. Stem end blockage and water stress are two problems in decreasing the vase life of chrysanthemum ...
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Introduction Chrysanthemum (Chrysanthemum morifolum L.) is one of the most important cut flowers in the world, which currently ranks second in the world after rose in terms of economy and cultivation. Stem end blockage and water stress are two problems in decreasing the vase life of chrysanthemum cut flowers. Cut flowers undergo physiological and biochemical alterations which often lead to an early senescence. Steps to delay the senescence process rely on consideration of many aspects of handling process particularly the preservative solution that will influence the quality and longevity of the flowers. Many flowers are harvested before they are fully developed, to ensure a long postharvest life and to minimize mechanical damages which may occur during handling. Many researches have been performed to prolong the vase life of chrysanthemum cut flowers with different treatments like essential oils, organic acids and nanoparticles. Essential oils are aromatic oily liquids obtained from some aromatic plant materials. In vase solution, microorganisms cause stem obstruction and accelerate the aging of petals. Microorganisms and their toxic products restrict water uptake by blocking the end of the stem. Water balance, which is an important factor in maintaining the quality and longevity of cut flowers and the inability to uptake water are the main causes of senescence. The presence of disinfectants in the vase solution prevents the growth of microorganisms, protects the vessels against disintegration, and ultimately increases the vase life. Most of nanoparticles have antibacterial effects and their application in vase solution hinders microorganism growth and vascular blockage. Nanoparticles have high area-to-volume ratio, high efficiency, and low toxicity. Some nanoparticles penetrate into the cells of bacteria, disrupt their respiration chain, and cause disorder in their cell division, thereby killing them. They also inhibit the accumulation of bacteria in vase solution and stem end of cut flowers. Various studies have reported the positive impact of nanoparticles on decreasing microbial load, reducing transpiration from leaf surface, and preserving water uptake. Studies on postharvest longevity of chrysanthemum cut flowers using these compounds is low. Therefore, the aim of the present study was to evaluate the effect of orange spring essential oil, fulvic acid and cupper nanoparticles on vase life and some physiological parameters of chrysanthemum cut flowers. Materials and MethodsThe experiment was performed based on randomized completely design with three replicates in order to investigate the effect of different levels of fulvic acid (50, 100 and 150 mg l–1), orange spring essential oil (10, 30 and 50%) and copper nanoparticles (5, 10 and 20 mg l–1) in comparison to control (distilled water + 3% sucrose + 30 mg l–1 8-hydroxyquinoline sulphate) on postharvest parameters of chrysanthemum cut flowers. Measured parameters included vase life, solution uptake, vase solution bacterial population, stem end bacterial population, decreasing the brix degree, decreasing fresh weight, dry matter, total chlorophyll content, carotenoid content, protein content, and peroxidase and superoxide dismutase activity. Data were analyzed by SPSS statistical software package and means were compared with the LSD test at the probably level of 95%. Results and DiscussionAccording to the obtained results, the effect of treatments on improving the quality characteristics of chrysanthemum cut flowers after harvest was significant. Results showed that the high vase life (16.33-17.00 days) was obtained with all three copper nanoparticles concentrations. The vase life of chrysanthemum cut flowers was extended to 17 days by the addition of 20 mg l–1 copper nanoparticles in preservative solution in compared to control with 14 days’ vase life. Least solution bacteria colonies was obtained through the use of 5 mg l–1 copper nanoparticle. On the other hand, least stem end bacteria colonies was obtained using 10 and 30% orange spring essential oil. Solution uptake in these treatments was high, too. The effects of different treatments on some other physiological traits and antioxidant enzymes activity were measured. Many studies have been carried out on the effect of essences (herbal extracts) as antimicrobial agents on prolonging the vase life of cut flowers. In most of these studies, these essences could prolong postharvest life. Essences have been studied with the intension of incorporating them into integrated pest management to avoid or reduce the use of synthetic bactericides and fungicides. They also have antioxidant properties. Application of herbal extracts improved water absorption in rose cut flowers by preventing the vessel obstruction. The above results are similar to the results of this study. In most cases, when the cut flowers were treated with nanoparticles, they exhibited longer vase life, higher water uptake, and lower stem-end bacteria than the control flowers.
Postharvest physiology
Kazem Hosseinzadeh Moghaddam; Behzad Kaviani; Davood Hashemabadi; Shahram Sedaghathoor; Mohammad Reza Safarimotlagh
Abstract
IntroductionKiwi (Actinidia deliciosa) is rich in minerals, vitamins and antioxidants. Kiwi fruit is sensitive to ethylene and has high perishability. There are some physical and chemical methods to delay aging and maintain postharvest quality of fruits. Light irradiation is a physical and pollution-free ...
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IntroductionKiwi (Actinidia deliciosa) is rich in minerals, vitamins and antioxidants. Kiwi fruit is sensitive to ethylene and has high perishability. There are some physical and chemical methods to delay aging and maintain postharvest quality of fruits. Light irradiation is a physical and pollution-free method that has been reported to be effective in controlling fruit decay and increasing its shelf life. Sodium nitroprusside (SNP) acts as an important signal in some physiological activities of the plant. SNP improved the quality and durability after fruit harvest in some fruits.Amino acids are effective in delaying the aging process and increasing the postharvest life of horticultural crops. Arginine plays an important and vital role in plant growth and development processes. The positive effect of arginine in increasing the shelf life of some fruits has been reported. The aim of this study was to increase the shelf life and quantitative and qualitative characteristics of ‘Hayward’ kiwi fruit after harvesting with the use of blue light, SNP and arginine. Material and MethodsHealthy and uniform fruits were selected and exposed to blue light (6, 12 and 24 h) at a wavelength range of 470 nm by LED lamps, SNP (0.5, 1 and 2 mM) and arginine (0.5, 1 and 2 mM). The experiment was performed in a completely random design with 10 treatments in 3 replications with 30 plots and 10 fruits per plot. After immersing the fruits at different levels of arginine, SNP and distilled water (control treatment), the surface of the fruits was dried and then sterilized. The fruits were monitored daily and their quantitative and qualitative properties were recorded during the experiment. Parameters of shelf life, tissue firmness, flavor index, loss of fresh weight, proline, ionic leakage, malondialdehyde (MDA), and dry matter, as well the activity of ascorbate peroxidase (APX), peroxidase (POD) and superoxide dismutase (SOD) enzymes were measured. Analysis of data obtained from sampling during the experimental period and laboratory were performed using SPSS statistical software and comparisons of means was done based on LSD statistical test. Results and DiscussionThe results showed that SNP at a concentration of 2 mM caused the highest shelf life (117.20 days) and the highest proline content (80.14 mg/kg) in kiwi fruits. The reason for this increased shelf life may be that SNP delays ethylene production process by activating the genetic and biochemical mechanisms, thus increase the postharvest life of ethylene-sensitive products. The highest firmness (4.56 kg/cm2) and the lowest fresh weight loss (1.26%) was obtained in fruits treated with 12 h of blue light. Some of the most important causes of this finding are that blue light delays the peak time of ethylene production, and as a fungal agent, reduces fruits decay after harvesting. The data showed that 12-h irradiation of blue light and 2 mM SNP caused a significant increase in the amount of antioxidant enzymes (SOD, POD and APX) of kiwifruit. Other traits such as flavor index, dry matter content, ion leakage and malondialdehyde were also measured. Blue light treatment can effectively reduce the decay of many fruits during postharvest storage. The study on kiwifruit showed that the qualitative treatments of different lights on various cultivars at different times had a significant effect on some physiological, morphological and gene expression traits. LED irradiation was found to be a suitable method for improving the quality of nutrients and the quality of flavor after harvest of some fruits. SNP was a good treatment to maintain fruit quality and improve disease resistance in kiwi cultivar ‘Bruno’ during storage. Fruits treatment with arginine is a promising technology to reduce cold and brown damages by stimulating the activity of antioxidant enzymes. Plant resistance to environmental stresses due to the use of arginine is in order to the effect of this substance on polyamine accumulation through increasing arginine decarboxylase and ornithine decarboxylase enzymes and increasing proline accumulation by enhancing ornithine amino-transferase enzyme activity as well as increasing nitric oxide through increasing the activity of nitric oxide synthase enzyme. Quality of kiwi fruit decreases during storage due to rapid softening and contamination with some fungi. In this study, effective treatments were used to reduce these complications. Overall, the results of this study showed that 2 mM SNP caused the highest shelf life. The highest firmness and the lowest fresh weight loss were observed in fruits treated with 12 h blue light. 12-h irradiation of blue light and 2 mM SNP caused a significant increase in the antioxidant enzymes of kiwifruit.
Pomology
Behzad Kaviani; Maryam Jamali; Mohammad Reza Safari Motlagh; Ali Reza Eslami
Abstract
Introduction Pears have a high nutritional and economic value worldwide. One of the major problem in growing pear cultivars is their late fertility on seed bases. To solve this problem, using asexual propagation methods can lead to the production of root trees. Cuttings are commonly used for proliferation ...
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Introduction Pears have a high nutritional and economic value worldwide. One of the major problem in growing pear cultivars is their late fertility on seed bases. To solve this problem, using asexual propagation methods can lead to the production of root trees. Cuttings are commonly used for proliferation either softwood, semi-hardwood or hardwood. Clonal propagation is considered proper in rapid propagation of shrubs and trees species. Adventitious root formation in stem cuttings is a crucial physiological process for vegetative propagation of many plant species. Rooting ability of tree species through stem cuttings is affected by several factors particularly plant growth regulators. Rooting of pear stem cuttings is time consuming. Auxin is effective in stimulating root formation on cuttings. The most widely used auxins in rooting of stem cuttings are indole-3-butyric acid (IBA) and naphtaleneacetic acid (NAA). Of these two auxins, IBA is the most widely used root promoting chemical, because it is nontoxic over a wide range of concentrations. Applied concentration is an important factor. Typically, a concentration of 2000 to 4000 ppm will result in good rooting for most shrubs and trees.Materials and Methods In this experiment, pear (Pyrus communis) was used as mother plants. Stem cuttings were used as plant materials in this experiment. The effect of different levels of indolebutyric acid (IBA) and naphthalene acetic acid (NAA) was studied on the rooting of pears in a factorial experiment based on a randomized complete block design with 16 treatments and 4 replications. The experimental treatments included IBA and NAA at the rates of 0, 1000, 2000 or 4000 mg L-1. Rooting percentage, rooting time, root number, root length, root volume, plant height, leaf number and fresh and dry weights of cuttings were measured after about 130 days.Results and Discussion The results showed that the highest rooting (3.56 per seedling) was observed in cuttings treated with 4000 mg L-1 IBA. Also, the highest root number was obtained from the treatment of 1000 mg L-1 NAA and 2000 mg L-1 IBA with an average number of 0.16 roots per plant. According to the means comparison for the simple effect of IBA on the rooting time, the highest rooting time was related to the application of 4000 mg L-1 IBA. The results revealed that plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA grew the longest roots. Also, ANOVA showed that among the applied factors, only the simple effect of IBA was significant on root volume. Means comparison for the simple effect of IBA on root volume showed that the highest was related to the application of 2000 mg L-1 IBA. According to the means comparison for the interactive effect of IBA × NAA on cutting fresh weight, the highest fresh weight was, on average, 8.36 g in plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA. As well, means comparison the effect of IBA × NAA on cutting dry weight showed that the highest dry weight was 15.9 g related to the application of 4000 mg L-1 NAA × 2000 mg L-1 IBA. It was also observed that 2000 mg L-1 NAA × 1000 mg L-1 IBA was related to the longest cutting with an average length of 2.82 cm. Finally, plants treated with 4000 mg L-1 NAA and 2000 mg L-1 IBA produced the highest number of leaves (15.9 g, on average). One of the effective factors in the success of vegetative propagation of plants with stem cuttings, especially woody plants with hard-rooting stems, is the production of more roots in a short time. Plant growth regulators, including auxins, play an important role in this regard. The effect of auxins on the percentage and number of roots produced on stem cuttings has been shown by many researchers on various plants, including plants with hard-rooting cuttings particularly in trees. The most widely used auxins in this regard are IBA and NAA, respectively. The individual or combined effect of auxins for successful rooting depends on a number of factors, including plant type, cuttings type, cuttings size, cuttings age, and the time of year the cuttings were removed. In the present study, the combined effect of IBA and NAA had the greatest effect on most of the measured traits.
Pomology
Mohammadreza Safari Motlagh; Behzad Kaviani; Jaleh Ashegh
Abstract
Introduction: In recent years, applying humic acid has been common in enhancing the quantitative and qualitative characteristics of crops. The use of biofertilizers instead of chemical fertilizers has an effective role in increasing the health of plants, animals, and humans, and reducing environmental ...
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Introduction: In recent years, applying humic acid has been common in enhancing the quantitative and qualitative characteristics of crops. The use of biofertilizers instead of chemical fertilizers has an effective role in increasing the health of plants, animals, and humans, and reducing environmental pollution. Chemical fertilizers are gradually being replaced by biofertilizers. Strawberry is a fruit with high nutritional value. Choosing the right nutritional conditions such as fertilizers and suitable cultivation beds to achieve high quantitative and qualitative yield in this plant is inevitable. In recent years, the use of humic acid has been common in enhancing the vegetative and generative characteristics of crops. Humic acid is a rich source of potassium, phosphorus and nitrogen. The method of application of humic acid has an effective role in improving the quantitative and qualitative characteristics of plants. Combining some cultivation beds such as perlite, composts, and fertilizers including agricultural waste (such as rice bran and tea wastes) into soil cultivation beds have had an effective role for improving the quantity and quality of plants. Materials and Methods: A pot experiment was conducted to evaluate the effects of foliar application of humic acid and different cultivation beds on morphology, flowering and fruiting of two strawberry (Fragaria × ananassa) cultivars ‘Local’ and ‘Selva’ in Islamic Azad University, Rasht Unit, on 2016. Different concentrations of humic acid (0, 300, 600, and 1000 mg l−1) were applied as foliar application in two steps (late March containing three leaves and late April containing five leaves) on strawberries cultivated in different beds (usual soil and usual soil with rice bran, or perlite, or tea wastes). The experiment was carried out as factorial based on a randomized complete block design (RCBD) with four replications. Some traits including plant height, root number, root length, leaf length, shoot number, shoot length, shoot diameter, leaf number, node number, flowering time, flower diameter, flower number, fruit number and fruit weight were measured. Results and Discussion: Analysis of variance showed that the interaction effect of humic acid × cultivation bed ×cultivar on plant height, shoot length, shoot number, leaf number, root length, root number, flower diameter (p≤0.01), fruit weight, and fruit number (p≤0.05) was significant. The interaction effect of these three factors on shoot or stolon diameter, leaf length, flowering time and flower number was not significant. Results of mean comparison showed that the highest shoot or stolon number (14.82) were obtained in ‘Selva’ cultivar treated with 1000 mg l−1 humic acidcultivatedin usual soil with tea wastes. The highest fruit weight (35.45 g) and fruit number (15.41 per plant) were obtained in ‘Selva’ cultivar treated with 1000 mg l−1 humic acidcultivatedin usual soil with perlite. The maximum leaf number (16.03 per plant) was obtained in the treatment of 300 mg l−1 humic acid and the cultivation bed of usual soil and rice bran in ‘Local’ cultivar. Minimum fruit number (3.58) and fruit weight (8.23 g) were obtained in ‘Local’ cultivar cultivated in usual soil bed without humic acid. The highest number of root (19.56) was obtained in the treatment of 600 mg l−1 humic acid and the cultivation bed of usual soil with perlite in ‘Local’ cultivar. The highest amount of flower diameter (7.85 mm) was calculated in the treatment of 1000 mg l−1 humic acid and the cultivation bed of usual soil with tea wastes on ‘Selva’ cultivar. These results suggest that humic acid foliar application might be benefit to enhance fruit characteristics of strawberry. Totally, humic acid application increased growth and yield of strawberry. Since the most important parameters for increasing the quality of strawberry fruit is fruit characteristics, it is recommended to use 1000 mg l−1 of humic acid cultivated in the usual soil mixture with tea wastes. Strawberries are widely cultivated worldwide due to their high nutritional value. Chemical fertilizers have been used as a way to increase crop yields, but have led to problems such as nitrate accumulation, pot life, and poor quality and environmental pollution. Therefore, organic fertilizers have been used. Humic acid can improve quantitative and qualitative production by having properties such as providing more available essential elements and increasing plant resistance to various biological and non-biological stresses. A positive association has been reported between the use of humic acid and the increases in growth, yield and product quality in strawberries and other plants. Proper cultivation bed plays an important role in the optimal growth and development of plants. Salinity increases osmotic stress, ion toxicity, oxidative stress and food imbalance. The use of compost fertilizer and foliar application of humic acid increased the growth, yield and quality of strawberry fruit.
