Postharvest physiology
Mohsen Mohammadi; Davood Hashemabadi; Behzad Kaviani
Abstract
Introduction
Cut tuberose flowers face challenges such as reduced vase life and postharvest quality deterioration. This problem is mainly caused by various factors such as dehydration, vascular blockage due to bacterial growth, ethylene accumulation and oxidative stress, which lead to a reduction in ...
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Introduction
Cut tuberose flowers face challenges such as reduced vase life and postharvest quality deterioration. This problem is mainly caused by various factors such as dehydration, vascular blockage due to bacterial growth, ethylene accumulation and oxidative stress, which lead to a reduction in the postharvest lifespan of flowers. To address these challenges, the use of chemical and natural compounds has been considered an effective method to extend postharvest longevity and maintain the quality of cut flowers. Aluminum sulfate helps to preserve the freshness of cut flowers by reducing microbial growth, improving water uptake and preventing vascular blockage. The use of aluminum sulfate in vase solutions has shown to increase of the postharvest lifespan in certain cut flowers, such as roses, gardenias and lisianthus. Plant essential oils (containing phenol), possess antioxidant, antibacterial and antifungal properties. They can inhibit microbial growth in vase solutions and prevent cellular damage caused by reactive oxygen species (ROS) or free radicals. The positive effects of certain essential oils on extending the vase life of some cut flowers, including gerberas, roses and alstroemerias, have been reported. Cobalt chloride prevents vascular blockage caused by bacterial agents in stems and maintains a high-water flow rate, leading to improved water uptake by cut flowers. This salt can also extend vase life by inhibiting ethylene production, preventing its accumulation and reducing respiration. The beneficial effect of cobalt chloride on increasing the vase life of some ornamental cut flowers, including roses, carnations, tuberoses, gladiolus and chrysanthemums, has been reported. 8-Hydroxyquinoline sulfate (8-HQS) is an inhibitor of ethylene production and reduces respiration rate. In cut flowers such as dendrobium, gerbera and gladiolus, 8-HQS extended the vase life by preventing microbial growth, reducing respiration rate and enhancing water absorption. This study aimed to investigate the effects of aluminum sulfate, Eryngium spp. essential oil, cobalt chloride and 8-HQS on the postharvest longevity of cut tuberose flowers (Polianthes tuberosa).
Materials and Methods
Cut tuberose (Polianthes tuberosa) flowers were obtained from a commercial producer in Tehran Province. To standardize the stem length, all flowers were recut at a 60 cm distance under water and immediately transported to the postharvest laboratory at the Faculty of Agriculture, Islamic Azad University, Rasht Branch, to prevent dehydration. Upon arrival, the flowers were placed in distilled water to maintain hydration. For the experiment, five cut flowers were placed in each 2-liter plastic vase and then treated with specific concentrations of the experimental factors. The study was conducted based on a completely randomized block design with three replications. The effects of different concentrations of aluminum sulfate (50, 100 and 150 mg/L), Eryngium essential oil (10, 20 and 40%), cobalt chloride (200, 300 and 400 mg/L) and 8-HQS (100, 200 and 400 mg/L) on cut flowers parameters such as vase life, water uptake, fresh weight loss, chlorophyll content, malondialdehyde (MDA) as an indicator of lipid peroxidation, bacterial colony count and antioxidant enzyme activity were evaluated. Thus, the present experiment consisted of 12 treatments, 3 replications and 5 flower stems per replication, totaling 36 experimental units (plots). Treatments were applied permanently, with each treatment prepared based on a 500 mL volume in the plastic vase. Data were subjected to analysis of variance (ANOVA) and means were compared by the LSD at P < 0.05 using the SAS ver. 9.2 software.
Results and Discussion
The results showed that treatment with aluminum sulfate significantly increased vase life and prevented fresh weight loss. Aluminum sulfate improved water uptake and preserved chlorophyll content, thereby enhancing the longevity of the flowers. Eryngium essential oil also had a positive effect on maintaining flower quality due to its antimicrobial and antioxidant properties. Results of the variance analysis showed that treatments with aluminum sulfate, Eryngium essential oil, cobalt chloride and 8-HQS significantly increased the vase life of tuberose cut flowers (P < 0.01). The effect of treatments was significant for most traits. The longest vase life (12 and 11.50 days) was observed in aluminum sulfate at 100 and 50 mg/L, respectively, while the control treatment had a vase life of only 8 days. The highest water uptake was observed in treatments with aluminum sulfate (100 mg/L), 8-HQS (200 mg/L) and Eryngium essential oil (10 mg/L). The control treatment had the highest bacterial population at the stem base (33 CFU/mL) and vase solution (73 CFU/mL). 8-HQS (400 mg/L) showed the lowest bacterial population at the stem base (4 CFU/mL). Just some treatments were selected for measurement of enzymes activity. Among the selected treatments, Eryngium essential oil (20 mg/L) exhibited the highest peroxidase (POD) enzyme activity, while the control treatment (0.07 µmol/g fresh weight) had the lowest. The control treatment (9.47 µmol/g fresh weight/min) showed the highest catalase (CAT) enzyme activity, while cobalt chloride (300 mg/L, 1.84 µmol/g fresh weight/min) had the lowest. Aluminum sulfate can partially reduce ethylene production and respiration rate in cut flowers. It primarily acts as an antimicrobial agent, indirectly extending vase life. Some studies suggest aluminum may moderately reduce lipid peroxidation in cell membranes. The aluminum ion may interact with cell walls, enhancing tissue rigidity and delaying wilting. Studies on roses, peonies and gladiolus confirmed that aluminum sulfate delays senescence by inhibiting microbial growth, preventing bacterial blockage and improving water uptake. Plant essential oils (e.g., in tuberose, chrysanthemum, gerbera, gladiolus and carnation) extend postharvest life due to their antimicrobial and antioxidant properties, reducing microbial load in vase solutions and ethylene production. 8-HQS, as a disinfectant, extended vase life in peonies, dendrobium and gladiolus by inhibiting bacteria, enhancing water uptake, delaying senescence, suppressing ethylene and reducing respiration rate. Increased POD activity in treated flowers indicates enhanced antioxidant defense, crucial for neutralizing free radicals and mitigating oxidative stress. Reduced CAT activity in treated tuberose flowers may result from lower ROS production, direct inhibition of enzyme activity, hormonal/metabolic signaling changes and delayed oxidative stress and senescence.
Conclusions
These findings suggest that the use of these compounds particularly aluminum sulfate at the concentration of 100 and 50 mg/L can be an effective method to improve the postharvest longevity and quality of cut tuberose flowers.
Medicinal Plants
B. Kaviani; R. Mohammadipour; D. Hashemabadi; M.H. Ansari; R. Onsinejad; A.R. Berimavandi
Abstract
IntroductionDamask rose (Rosa damascena Mill.) is used as a multi-purpose species. The flower essential oil of this plant has many applications in various industries. There is a wide variety of morphological, phonological, flower shape, yield and yield of essential oils among genotypes and different ...
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IntroductionDamask rose (Rosa damascena Mill.) is used as a multi-purpose species. The flower essential oil of this plant has many applications in various industries. There is a wide variety of morphological, phonological, flower shape, yield and yield of essential oils among genotypes and different populations of Damask rose in various ecological conditions in Iran. Evaluation of genetic diversity among Damask rose of Iran is important in order for breeding purposes. Some studies on phenotype, essential oil and genetic diversity were also carried out among different cultivars of rose flowers in other parts of the world. Significant diversity has been reported among the populations and genotypes of rose in different ecological conditions for many traits. Identifying superior species, cultivars and populations is important for commercial cultivation and more essential oil production. It is difficult to understand genetic diversity in roses because natural hybridization and spontaneous mutations with high abundance occurs in this plant. Morphological differences can be due to the geographical coordinates, natural hybridization and mutations. The purpose of this study was to investigate and compare the genetic variety of Damask rose in Guilan, Ilam, Golestan, Tehran and Kashan in order to introduce superior genotype based on essence content and some other morphological and physiological traits. Materials and MethodsFive genotypes of Damask rose including Kashan, Ilam, Golestan, Tehran and Guilan genotypes were evaluated as plant materials. Plant materials were collected from mentioned-above regions as root-sucker and transferred to the farm of Research Institute of Forests and Rangelands of the country. The experimental design used was a completely randomized block, which was performed with 3 replications and was considered for each 5-suckers’ repetition (total: 75 suckers). In each replication, three specimens of each genotype were planted in pits with diameter and depth of 50-60 cm. The distance between scions per rows was 2.5 meters and row spacing from each other was 2 meters. During the experimental period, the bushes were irrigated using drip (trickle) irrigation method. The sampling was performed to measure morphological and physiological parameters after the blooms were opened in early May. Evaluated parameters were plant height, leaf length, leaf width, leaf area, petal number, stamen number, carpel number, fresh weight of petals, petal anthocyanin levels, petals essential oil levels, chlorophyll content and leaf carotenoids. Data were analyzed by ANOVA and, if significant, Tukey analysis was used. SPSS software was employed for statistical analysis. Results and DiscussionThe results showed that the highest amount of essential oil (0.042 and 0.038%) was extracted from the petals of Ilam and Kashan genotypes, respectively. The highest petal weight (2.70 and 2.30 g) was related to the petals of Ilam and Kashan genotypes, respectively. The highest petal length and width were obtained in these two genotypes. The largest number of petals (71.80 per each plant) was related to Guilan samples. The highest amount of chlorophyll a was related to Ilam genotype and the highest amount of chlorophyll b, carotenoids and anthocyanin was related to Kashan genotype. In the present study, rose flower genotypes collected from different parts of Iran showed significant diversity in relation to morphological and physiological properties, especially essence. The results of the present study showed that there was a significant correlation between the amount of essence in the petals and the weight and dimensions of the petals. Similar findings related to the correlation between flower yield and its components in roses flowers were presented in some studies. Some studies have shown that the weight of the flower has a very strong, positive and significant correlation with the flower yield. Despite the geographical distance between some genotypes, the high similarity coefficient between them may indicate the common origin or continuous and purposeful genotypes. On the other hand, the low similarity coefficient between genotypes proposes relatively low geographical connection and different primary origin. In the present study, there was a low correlation between the amount of essence in the petals and the weight and dimensions of the petals in the Ilam and Kashan genotypes with the Golestan and Guilan genotypes. Generative traits, including flower characteristics, are more suitable for genetic and evolutionary evaluations than vegetative traits. The results of some researchers in Iran and elsewhere in the world showed that flower yield per plant is associated with some other traits, including flower number, dimensions and weight of flowers, and the number of branches in the plant. The genetic analysis of rose flower genotypes showed that some genotypes collected from different areas are genetically relevant and some are separate. This subject shows effective role of ecological conditions in changing and variability of different species and varieties. The results indicated that the difference in the amount of essential oil compounds is mostly influenced by environmental and physiological factors. ConclusionThe morphological differences observed among the flower genotypes indicate the presence of valuable germplasm and a strong potential for trait improvement. These differences also demonstrate the feasibility of selecting superior genotypes using morphological markers to enhance flower yield within the country. Overall, the Ilam and Kashan genotypes are recommended as promising candidates for use in breeding programs. AcknowledgementWe thank Islamic Azad University, Rasht Branch for its assistance.
Pomology
S. Keivanfar; D. Hashemabadi; B. Kaviani
Abstract
IntroductionOlive (Olea europea L.) fruit ripening is a slow and long process and has a great impact on fruit quality, including the amount of oil. Also, interrupting the harvest and extraction of olive oil causes unfavorable conditions in this fruit. Therefore, it is important to determine the best ...
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IntroductionOlive (Olea europea L.) fruit ripening is a slow and long process and has a great impact on fruit quality, including the amount of oil. Also, interrupting the harvest and extraction of olive oil causes unfavorable conditions in this fruit. Therefore, it is important to determine the best time to harvest the fruit. Olive oil has unsaturated fatty acids and has an antioxidant activity. The analysis of maturation stages is a prerequisite for fruit harvest time in each cultivar and quality of olive products. The time of harvest and maintenance after harvest is two important factors in the quality and quality of olive fruit oil. The exact determination of olive harvest time depends on the geographical area, cultivar and climate, agronomic and fruiting conditions. Study on different olive cultivars in different regions of Iran and the world revealed that fruit harvest time plays an effective role on the morphological, physiological and metabolic parameters of fruit. The approximate time of olive fruit harvest is in different geographical points, November and October. The purpose of this study was to investigate the right time of olive fruit harvesting 'Arbequina' and 'Yellow' cultivars for obtaining maximum quality of fruit and oil. Materials and MethodsA factorial experiment containing two factors; cultivar in two levels ('Yellow' and 'Arbequina') and harvest time in six levels (24th and 31th October, and 7th, 14th, 21th and 28th November) based on a completely randomized block design with two factors in 12 treatments, 3 replicates and 36 experimental units was done to determine the appropriate harvest time and its effect on oil quality. Physiologic parameters; percentage of oil, amount of phenolic compounds, degree of peroxidation, amount of oleic acid, force of separation of fruit from tail and acidity were evaluated. This research was conducted at the olive research station in Rudbar city in southern Guilan province using the removed olives from the Manjil ETKA station. The 6 trees from two cultivars; 'Arbakkin' and 'Yellow' (from each 3 tree) which were similar in terms of height, age, crown diameter, mean conditions and irrigation were evaluated. Trees were planted at 6 × 8 m intervals. After selecting trees, from each tree, 2 to 3 kg of olive was randomly harvested. In fruits with tail, the force needed to separate the tail of the fruit was measured by the force assessment device. Standard method numbers 4178 and 4179 standard institutes and industrial research of Iran were used to measure acidity and olive oil peroxide, respectively. Polyphenols were measured with spectrophotometer. To determine the percentage of oil, saccule was used. For measurement of oleic acid, gas chromatography (GC) was used. Data were analyzed using SAS software and their average comparison was done by Duncan. Results and Discussion Mean comparison of the interaction effect between cultivar and harvest time showed that the highest acidity of the fruit was obtained in 'Arbequina' cultivar, respectively harvested at two times 31th and 24th October. The highest fruit peroxide value and the highest percentage of oleic acid were calculated in 'Yellow' cultivar in 24th October. The highest value of polyphenol was obtained in 'Yellow' cultivar on 7th November. The highest percentage of fruit oil was obtained in 'Arbequina' cultivar on 31th October. The lowest force to separate the tail from the fruit was applied in 'Arbequina' cultivar on 31th October. The results showed that the best time to harvest 'Yellow' cultivar is 7th November and for 'Arbequina' cultivar is 14th November. The study on several olive cultivars in China showed that the most suitable fruit harvest time was in late October until mid-November. There was an adverse significant correlation between changes in total sugar content in fruit and leaf and oil accumulation in the fruit. The quality of fruit depends mainly to the type of cultivar, genetic characteristics, maturity and environmental conditions. Study on some olive cultivars showed that the ratio between sugars is different in various stages of fruit maturity and between different cultivars of olive fruit. Some studies have shown that the most suitable time of olive fruit harvest for canned preparation is early September and for extraction of oil, late September. Fruits should be harvested when they have the highest oil accumulation. The study on 'Koroneiki' and 'Mission' cultivars in Gorgan region showed that the amount of oil in the dry matter and the percentage of free fatty acids increased with increasing degree of maturity, while peroxide value was reduced. One of the causes of peroxide value reduction during maturity is reduction in lipoxygenase enzyme activity. This enzyme increases the peroxide value by effect on linolenic acid and linoleic acid. Based on these results, the best time to harvest for the above cultivars is early in December. ConclusionsHarvest time and proper storage after harvest are two important factors of olive oil quantity and quality. In both cultivars, a longer delay in harvesting compared to the mentioned-above dates increases the percentage of oil, but it has a negative effect on the reproductive stages of the next year, and perhaps one of the causes of olive aging is excessive delay in harvesting. It is important to pay attention to the above two items.
Breeding and Biotechnology of Plant and Flower
D. Hashemabadi; B. Kaviani; K. Shakeri Kiasaraei; R. Onsinejad; M. R. Safari Motlagh
Abstract
Introduction Tulip flower (Tulipa L.) from the family Liliaceae is a bulbous and monocotyledon plant that has the highest level under cultivation among this family group. Tulips can be propagated by seeds and bulbs. Its seeds produce bulbs up to two years after planting and it takes ...
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Introduction Tulip flower (Tulipa L.) from the family Liliaceae is a bulbous and monocotyledon plant that has the highest level under cultivation among this family group. Tulips can be propagated by seeds and bulbs. Its seeds produce bulbs up to two years after planting and it takes six years for the bulbs to reach the flowering stage. In fields, the quality characteristics of flowers can be changed to some extent by changing some planting characteristics such as planting pattern and plant density. Some researchers have reported changes in the quantitative and qualitative characteristics of various crops and orchards, including ornamental plants, with changes in planting pattern and plant density. One effect of changes in planting patterns and plant density is alterations in photosynthesis and plant growth regulators. The purpose of this study was to identify the best planting pattern and determine the optimal planting density, as well as to examine the impact of these factors on the quantitative and qualitative characteristics of tulip (Tulipa L.) cv. 'Spryng'. Materials and MethodsTo evaluate the effect of planting pattern and density on growth and flower characteristics of tulip cv. ʹSpryingʹ, present study study was conducted as a factorial experiment based on completely randomized block design (RCBD) with 3 replications in 27 plots. The first factor was three planting patterns (square, triangle and rectangle) and three planting densities (25, 45 and 65 plant/m2) as the second factor. Morphological and physiological traits such as height, length and diameter of stem, leaf and flower, flowering time, cut flower number, flower longevity, number, diameter and weight of bulb and bulblet, and the content of chlorophyll and carotenoid were measured. Statistical analysis of data was performed with SAS 9 software and mean comparison of the data with LSD test at 5% probability level. Graphs were drawn in Excel. Results and DiscussionResults showed that the maximum number of cut flowers (59.90) was counted in plants cultivated in triangle cultivation design with planting density of 65 plants/m2. The lowest time to start of flowering (69.30 days) and the highest content of leaf chlorophyll (13.57 μg/ml) was obtained in plants cultivated in trianle cultivation design with planting density of 45 plants/m2. The most flower longevity (12.73 day) and the highest content of carotenoid (1.68 μg/ml) was obtained in plants cultivated in square cultivation design with planting density of 45 plants/m2. The height of the flowering stem is one of the important traits for the marketing of cut flowers. The results of the present study showed that the height of the tulip plant was affected by plant density and planting pattern. This result was consistent with the results reported by some researchers. At low plant densities, long plant spacing reduces plant competition for water and nutrient uptake, resulting in larger plant growth and leaf size. Also, long plant distances cause the roots to develop and grow, and the leaves to grow and thicken. Increasing the vegetative competition of adjacent plants at high densities causes photosynthetic organs to be placed in the shade (change in the quantity and composition of the received radiation spectrum in the shade leaves), which has a great effect on the balance of plant growth regulators, resulted in longitudinal and superficial growth of plant organs. It intensifies the longitudinal growth of the petiole and accelerates all the developmental processes of the plant. Plant morphology and angle of leaf deviation can also be effective in increasing leaf size. Uniform distribution of plants and greater absorption of light and nutrients increased leaf length and width. The results revealed that plants compete for light and nutrients, and in these competitive conditions, roots and stems are taller than optimal, and the distance between nodes increases. The effect of planting pattern on flowering process can be related to changes in plant photosynthesis and the availability of photosynthetic materials for the developing reproductive parts. Changes in planting distance or pattern can alter inflorescence characteristics by affecting root growth and modifying the production of plant growth regulators in the roots. These regulators are then transferred to the aerial parts, influencing inflorescence characteristics. Adjusting the planting distance or pattern can also impact various traits of bulbs and bulblets in bulbous plants. Competition for receiving maximum light and photosynthesis is a key factor in changing bulb and bulblet traits. This competition is influenced by planting arrangement and plant density. Some studies have shown that planting pattern and plant density affect the amount of plant pigments such as chlorophyll and carotenoids, the main reason being the difference in light intake.
Ornamental plants
B. Kaviani; N. Negahdar
Abstract
IntroductionPoinsettia (Euphorbia pulcherrima) from the family Euphorbiaceae is used as potted and cut flower and has great importance in floriculture industry. Appropriate application of nutrients and plant growth regulators has an important role in increasing the quantity and quality of crops. The ...
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IntroductionPoinsettia (Euphorbia pulcherrima) from the family Euphorbiaceae is used as potted and cut flower and has great importance in floriculture industry. Appropriate application of nutrients and plant growth regulators has an important role in increasing the quantity and quality of crops. The successful application of various nanoplatforms in medicine under in vitro conditions has generated some interest in agro-nanotechnology. This technology holds the promise of controlled release of agrochemicals and site-specific targeted delivery to improve efficient nutrient utilization and enhanced plant growth. Nanoencapsulation shows the benefit of more efficient use and safer handling of pesticides with less exposure to the environment. Thus, nanofertilizers can be substituted for conventional fertilizers. The role of iron in the activity of some enzymes such as catalase, peroxidase and cytochrome oxidase has been demonstrated. Iron is present as a cofactor in the structure of many enzymes. The results of some studies showed that in the absence of micro-nutrients elements, the activity of some antioxidant enzymes decreased, which resulted in increased sensitivity of plants to environmental stresses. The use of nano-iron fertilizer is an appropriate solution to remove this problem. Some growth retardants such as cycocel, paclobutrazol, bayleton and daminozide reduced the plant growth. Growth reduction in some ornamental plants enhances their overall quality and marketing. Cycocel is one of the most important growth retardants which inhibits gibberellin biosynthesis and activity in plant. Today, a range of artificially made growth-reducing compounds are used in the floriculture industry. The effect of plant growth retardants, depends on the time and method of application, concentration, species and varieties type, type of target organ and environmental and physiological conditions. Plant growth retardants reduce the division and elongation of stem cells. These compounds also reduce stem length and growth by having a negative effect on gibberellin structure. Therefore, the present study investigated the effect of different levels of nano-iron fertilizer and different concentrations of cycocel on growth and development of poinsettia (Euphorbia pulcherrima Willd.). Materials and Methods These experiments were carried out based on a randomized completely block design in three replications to evaluate the effect of various levels of nano iron chelated fertilizer and cycocel on growth parameters of Euphorbia pulcherrima. Cuttings with a height of 15 to 20 cm, each with 3 nodes, were prepared from the mother plant of poinsettia. Cuttings were placed in water within 24 hours for exudation of latex. Then, cuttings were planted in perlite for rooting. After rooting (60-65 days), cuttings were transferred into substrates including cocopeat, municipal compost and soil in ratio of 1:1:1. Poinsettia cuttings were grown in pots. Treatments include nano-iron fertilizer (0, 0.9, 1.8, 3.6 and 4.5 g.l–1) and cycocel (0, 500, 1000, 1500 and 3000 mg.l–1). Application of EDTA-based nano-iron chelate as foliar spray was performed on plants at the beginning of the experiment and 30 days later, as well as the use of cycocel 30 days after the start of the experiment as foliar spray. Stem height, internode length, node number, root length, root number, root volume, leaf number, leaf surface, leaf total chlorophyll content, iron content in leaf and the number and longevity of bracts were evaluated. Results and Discussion Results showed that the lowest plant height and the highest leaf number, root length, root volume, the number and longevity of bracts were obtained in treatments of 1.8 g.l–1 nano-iron chelate without or with the concentration of 1000 mg.l–1 cycocel. In some traits such as root volume and chlorophyll content, the minimum amount was calculated in the maximum of nano-iron chelate and cycocel concentrations. Suitable root characters were severely reduced through the use of 3000 mg.l–1 cycocel. Overall, the most suitable treatment, especially for reduction of stem height and enhancing some vegetative traits (such as leaf number) and flowering (such as bract longevity) was 1.8 g.l–1 nano-iron chelate along with 1000 mg.l–1 cycocel. Research has demonstrated that cycocel application reduces plant height in various species, including ornamental plants, as confirmed by this study. Furthermore, this study reveals a novel effect of cycocel: it alters the weight of both aerial and underground plant parts, alongside influencing leaf iron and chlorophyll content. Notably, plant growth retardants like cycocel are known to increase cytokinin content, which in turn can lead to elevated leaf chlorophyll levels.
Postharvest physiology
B. Kaviani; M. R. Safarimotlagh; S. 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.
Ornamental plants
A. Sahari Moghaddam; B. Kaviani; A. Mohammadi Torkashvand; V. Abdossi; A. R. Eslami
Abstract
IntroductionYew or English yew (Taxus baccata L.) from the family of Taxaceae is an ornamental shrub that is used in various industries. Root induction and formation process at the base of stem cuttings of yew is slow. This species is in danger of extinction. Stimulation of rooting in cuttings causes ...
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IntroductionYew or English yew (Taxus baccata L.) from the family of Taxaceae is an ornamental shrub that is used in various industries. Root induction and formation process at the base of stem cuttings of yew is slow. This species is in danger of extinction. Stimulation of rooting in cuttings causes the plant to grow faster. Polyamines are a group of plant growth regulators that play a variety of roles, including cellular differentiation and development and stimulation of adventitious root production. Some yew habitats have been destroyed because of neglect, destruction, livestock and ineffective exploitation. The yew is propagated by seeds or through cutting and grafting. Propagation of yew through seed is difficult and obtained plants show non-uniformity. Therefore, vegetative propagation is used to produce plants similar to the mother plant. The proliferation of the plant through leafy stem cutting is one of the most famous and the best propagation methods due to the preservation of the genetic structure and uniformity. Increasing the rooting capacity of trees and shrub cuttings is being carried out with a variety of plant growth regulators around the world. Putrescine has shown a better response in compare with other polyamines. The stimulation effect of exogenous application of polyamines, especially putrescine, was shown on the rooting of several plants’ cutting. Literature evaluation showed that there is not any study on the effect of polyamines on the rooting of the yew stem cuttings. Therefore, the aim of this research was to improve the rooting conditions of difficult-to-root cuttings with different concentrations of putrescine (a type of polyamine). Materials and MethodsIn order to investigate the effect of different concentrations of putrescine, an experiment was performed based on a completely randomized block design with 4 replications. Treatments included 0 (as a control), 500, 1000, 2000, 3000, 4000 and 5000 mg.l–1 of putrescine concentrations. In October, 25 cm of the end of the shoot of 5-years-old mother plants were cut and used as hardwood cuttings. The cuttings diameter was 2.5-3 mm. The lower ends of the shoot cuttings were kept at different concentrations of putrescine for 10 seconds and then placed in the cultivation bed. In this study, root percentage, number of roots, root length, stem length, shoot number, leaf number and survival percentage of cuttings were measured. Cuttings cultivation bed was perlite, cocopeat and peat moss. To prevent possible contamination, the bottom of the cuttings were immersed in a 2/1000 fungicide solution of Berdofix a week befor cutting preparation. Results and DiscussionThe results of analysis of variance showed that different concentrations of putrescine on all traits were significant at 1% probability levels. The results of mean comparison showed that the largest number of roots (6.50 per plantlet) and the highest root length (7.70 cm per plantlet) were observed in cuttings treated with 500 mg.l–1 putrescine. The highest number of shoots (5.50 per plantlet) and the highest rooting percentage (97.50) were obtained in cuttings treated with 2000 mg.l–1 of putrecine. The maximum number of leaves (41.25 per plantlet) was counted in cuttings treated with 3000 mg.l–1 of putrescine. Yew can be propagated successfully by stem cuttings. Natural conditions propagation and in vitro propagation beside cryopreservation are effective approaches to conserve plants particularly those putted in the red list. Plant growth regulators have an effective role in increasing the rooting of difficult-to-root cuttings of trees and shrubs. The exogenous use of polyamines as a new group of hormones stimulated root production in some cuttings. Peach × almond hybrid cuttings treated with 2 mM putrescine for 5 min showed the highest rooting percentage, root number and root length with the best quality. Putrescine is capable to influences on other plant growth regulators and has less toxicity than most of them. Polyamines stimulate cellular division in dissection place cells of cuttings such as cambium and phloem. The exogenous application of these compounds, especially putrescine during the root formation phase resulted in an increase in endogenous putrescine, endogenous auxin and peroxidase enzyme activity. In the cutting of the leafy stem of Corylus avellana L., the use of putrescine stimulated rooting. The study, like the present study, confirmed that putrescine can be useful for increasing rooting percentage and root quality. Putrescine had an effective role in the rooting of the stem cuttings. The present study revealed that the lowest root number was counted in cuttings that were not treated by putrescine (control). Polyamines (spermine, spermidine and putrescine) increased rooting percentage and root growth by stimulating root cell division (increased mitotic index of tip root cells) in regenerated pine (Pinus virginiana Mill.) seedlings. Polyamine biosynthesis and antioxidant enzymes activity were increased during root induction and formation. The exogenous application of spermidine in the apple (Malus prunifolia) stem cutting stimulated rooting by changing the concentration of some hormones. Spermidine regulated the expression of genes involved in the production of auxins. The study aimed to investigate the cellular-molecular effect of polyamines on the structure and development of roots in Arabidopsis showed that these organic compounds adjusted the size of the root meristematic zone during the effect on both symptomatic accumulations of hormones and reactive oxygen species (ROS). The same and different results are presented with the present findings by some other researchers. The main cause of these different results is the difference in the amount and balance of endogenous hormones, including polyamines in different species. Plant genotype, type of cuttings, cutting age, environmental factors, nutritional status especially type and amount of carbohydrates in the plant, the transfer rate of these carbohydrates from leaves to roots, the presence and the amount of phenolic compounds, nitrogen compounds, phonological stages and cutting season also play an effective role in these differences.
Postharvest physiology
K. Hosseinzadeh Moghaddam; B. Kaviani; D. Hashemabadi; Sh. Sedaghathoor; M. R. 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.
Postharvest physiology
S.A. Razi; D. Hashemabadi; B. Kaviani
Abstract
Introduction Carnation (Dianthus caryophyllus L.) is one of the most important cut flowers of the world. This flower is sensitive to postharvest ethylene and water stress and has short vase life. The use of retardants or inhibitors compounds of ethylene is an effective way to increase the postharvest ...
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Introduction Carnation (Dianthus caryophyllus L.) is one of the most important cut flowers of the world. This flower is sensitive to postharvest ethylene and water stress and has short vase life. The use of retardants or inhibitors compounds of ethylene is an effective way to increase the postharvest life of carnation. Polyamines including putrescine (diamine), spermidine (triamine) and spermine (tetraamine) as new groups of plant growth regulators that are involved in various processes including increasing cell division, increasing enzyme biosynthesis, regulation of different developmental stages, differentiation, flowering, embryogenesis, rooting and maturity. These compounds exert their anti-aging properties by competing with ethylene production. Polyamines are low molecular weight organic compounds with aliphatic nitrogen groups that have different hydrocarbon rings and two or more amino groups (positive charge agents). These organic compounds bind to cell membranes, nucleic acids, and other macromolecules and are involved in chromatin formation, ion channel control, free radical neutralization, and gene expression. Cell membrane strength and stability play an important role in increasing the post-harvest life of horticultural crops. Putrescine is the major polyamine in plants, which is a precursor to the synthesis of spermidine and spermine, and its positive effect on increasing the vase life of some cut flowers has been reported. Vase life of cut flowers of chrysanthemum, rose and gladiolus was increased by application of putrescine. The purpose of the present research was to increase the vase life of cut carnation flower using different putrescine concentrations and application methods. Materials and Methods A factorial experiment based on completely randomized design with 10 treatments in 3 replicates, 30 plots and 150 cut flowers was employed to investigate the effect of different concentrations of putrescine (0.01, 0.02 and 0.05 mM) and its application methods (continuous, pulse and spray) on vase life of cut carnation (Dianthus caryophyllus L.) flowers. Some other traits such as water uptake, dry mater percentage, decrease of fresh weight, the content of leaf chlorophyll and sepal carotenoid, POD and SOD enzymes activity, MDA, decrease of °Brix (sucrose percentage in flower stalk, soluble sugar in stem end and sepal), ionic leakage, ethylene were also measured. The statistical analysis of data was performed using SAS. The least significant difference (LSD) test at P < 0.05 was used for comparisons of different means of various treatments. Results and Discussion Results showed that the maximum vase life was recorded in cut flowers treated with 0.02 mM putrescine as spray application. The lowest ethylene production, the highest water uptake and superoxide dismutase enzyme activity was observed in 0.02 mM putrescine treatment. Some physiological parameters and enzymatic activity were also evaluated. The control treatment generally yielded the minimum values for most of the observed traits. Factors such as water stress, reduced carbohydrate levels, increased ethylene production, and the presence of microorganisms play pivotal roles in reducing the vase life of cut flowers. Polyamines are key in counteracting these stressors and delaying aging. They fulfill this role by fortifying the plasma membrane, suppressing the activity of hydrolytic enzymes, and inhibiting ethylene synthesis. Additionally, polyamines bind to cell wall pectin, safeguarding them from detrimental cell wall enzymes, including pectinase. They further impede flower maturation by inhibiting the production of essential enzymes required for ethylene synthesis and by dampening ethylene activity. Increasing polyamines by inhibiting lipid peroxidation is probably one of the mechanisms responsible for the anti-aging effect of polyamines. Polyamines have antioxidant properties so they reduce the number of oxygen free radicals and the permeability of plasma membranes by decreasing the activity of lipoxygenase, thereby increasing the vase life and quality of flowers. The use of polyamines to increase the vase life of some cut flowers has been reported, which the results of the present study are consistent with the results of these studies. Treatment of 20 mg l–1 spermine and 10 mg l–1 putrescine had the greatest effect on increasing vase life and reducing senescence of cut Alstroemeria flowers. Spermidine delayed the aging of carnation flowers. In cut rose cv. ‘Doles Vita’ flowers, the use of polyamines increased vase life. Treatment of 2 mM spermidine was the most suitable treatment to increase the vase life of cut carnation cv. ‘Red Corsa’ flowers. Cut rose flowers treated with humic acid and putrescine had the highest vase life compared to the control. Polyamines increased the vase life of cut gladiolus flowers by increasing the stability of plasma membranes. The addition of polyamines to the carnation flower preservative solution reduced their aging and prevented the production of ethylene. Polyamines appear to increase vase life in cut flowers by inhibiting ACC-synthase activity and reducing ethylene production. SOD, POD and catalase (CAT) enzymes, as antioxidant compounds, protect plants against reactive oxygen species and free radicals. Polyamines neutralize free radicals and are also involved in the synthesis of enzymes. Binding of polyamines to proteins protects them from the damaging effects of reactive oxygen species and free radicals. Treatment of 20 mg l–1 spermine increased the activity of SOD enzyme in cut Alstroemeria flowers. Concentrations of 10 and 20 mg l–1 putrescine and spermine significantly increased catalase activity. Spermidine treatment significantly increased the activity of free radical scavenging enzymes such as SOD and CAT. Putrescine in sunflower stimulated the catalase enzyme. At the first onset of senescence, antioxidant enzymes such as POD increase in petal cells to reduce the damaging effects of reactive oxygen species.
Postharvest physiology
A. Sharafshah Rostami; B. Kaviani
Abstract
Introduction Carnation (Dianthus caryphyllus L.), from Caryophyllaceae family, is one of the most important cut flowers in the world that its short vase life reduces the economic value. Postharvest longevity of cut flowers can be prolonged using carbohydrates (sugars) in a vase jar. Cut flowers ...
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Introduction Carnation (Dianthus caryphyllus L.), from Caryophyllaceae family, is one of the most important cut flowers in the world that its short vase life reduces the economic value. Postharvest longevity of cut flowers can be prolonged using carbohydrates (sugars) in a vase jar. Cut flowers undergo some physiological and biochemical changes that often lead to an early senescence. To delay the aging process in cut flowers, it is necessary to evaluate many aspects of preparation for storage conditions, especially preservative solutions that affect the quality and longevity of these flowers. Many flowers are harvested before they are fully developed, to ensure a long postharvest life and to minimize mechanical damages that might occur during handling. The growth and development of flower buds on cut flowers require food (especially carbohydrates), which is stored in the leaves and stems. These stored carbohydrates can be mobilized for the flower bud to use but maybe they are insufficient when the buds are harvested at a tight-bud stage. To maintain metabolic activities, including respiration, even for cut flowers that have reached full development, it is necessary to provide adequate reserves to achieve acceptable postharvest life. When stored materials are low, leaves and flowers age faster and the petals fade. Under these conditions, supplements can be provided to the flowers by adding sugars such as glucose, fructose and sucrose to the vase solutions. However, it is important to note that a sugar solution is also suitable for the growth of microorganisms, so that an antimicrobial agent should be added to the vase solution as well. Many researches were carried out on prolonging the vase life of cut carnation flowers with different preservative solutions together with an antimicrobial agent. Studies on postharvest longevity of cut carnation flowers using sugars as preservative solutions is low. Therefore, the aim of the present study was to evaluate the effect of sugars (glucose, fructose and sucrose) and application time on vase life and some physiological parameters of carnation cv. ‘Yellow Candy’ cut flowers.Materials and Methods A factorial experiment based on completely randomized design in three replicates was performed in order to investigate the effect of different levels (0, 50 and 100 g/L) of three types of sugars (glucose, fructose, and sucrose) and two sugar application times (the first and second 24 h, on 2019) on vase life of carnation cv. ‘Yellow Candy’ cut flowers. Some other traits such as water uptake, dry mater, relative fresh weight, protein and carotenoid of petal, leaf chlorophyll, POD and SOD enzymes activity and MDA were also measured. The statistical analysis of data was performed using Statistical Package for Social Sciences (SPSS) v 16.0. Least significant difference (LSD) test at P < 0.05 was used to find out the significance of differences among the mean values. Results and DiscussionResults showed that the effect of different levels of sugars on all evaluated traits was significant. Each three levels of sugars at each two applied times caused to increase vase life and relative traits. Maximum vase life (18 days) was obtained in 50 g/L glucose at the first 24 h with no statistically significant differences with the 100 g/L sucrose and fructose at the first 24 h. The highest water uptakes and dry matter, the lowest POD and SOD activity and minimum MDA were obtained in treatment of 50 g/L glucose at the first 24 h. The study found that the highest levels of petal protein content, chlorophyll a, b, and total chlorophyll were achieved in carnation "Yellow Candy" cut flowers treated with 50 g/L glucose after 24 hours of harvesting. The application of sugars at the first 24 hours after harvesting had a greater impact on improving the vase life of the flowers compared to the second 24 hours. Therefore, the use of glucose as an external holding solution, preferably within the early hours of harvesting, is recommended to prolong the postharvest life of carnation "Yellow Candy" cut flowers. The study also revealed that the use of external holding solutions, particularly sugars combined with antimicrobial agents, can have a positive effect on prolonging the vase life of cut flowers. The concentration of sugar required in the holding solution varies depending on the type of flower being treated, with most flowers requiring a concentration of 2% sugar. However, some flowers may require higher concentrations, up to 4-6%, while others may be damaged if treated with concentrations higher than 1%. The application of sucrose has been shown to increase glucose and fructose levels in petals, further supporting the use of external holding solutions containing sugars for extending the vase life of cut flowers. Therefore, it is important to examine each flower before treating it to determine the optimal concentration of sugars. Sugars are a source of energy and carbon for cut flowers and play an important role in decreasing the protein degradation and ethylene production, maintenance of osmotic balance, increasing water uptake, and finally delaying in senescence process
Pomology
B. Kaviani; M. Jamali; M. R. Safari Motlagh; A.R. 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.
Breeding and Biotechnology of Plant and Flower
N. Javaheri; B. Kaviani
Abstract
Introduction Lily, a member of the genus Lilium, belonging to the Liliaceae family is one of the most important commercial pot and cut flower species and one of the three major bulb crops in the commercial market because of its large, colorful and fascinating flowers. Lily hybrids are the most economically ...
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Introduction Lily, a member of the genus Lilium, belonging to the Liliaceae family is one of the most important commercial pot and cut flower species and one of the three major bulb crops in the commercial market because of its large, colorful and fascinating flowers. Lily hybrids are the most economically important plants with varied flowers. Hybrid Eastern lily (Lilium oriental hybrid ‘Casablanca’) is a perennial bulbous plant that its propagation by bulb in natural condition is time-consuming, so produces 1–2 bulblets per bulb scale in one years’ time which is not sufficient for large scale cultivation of this plant. One of the most important and best methods for vegetative propagation and breeding of lilies is in vitro bulb scale culture. In vitro adventitious bud regeneration from scales of Lilium rely on many factors like cytokinin and auxin concentrations such as BA and NAA. The successful use of tissue culture techniques for rapid propagation of some species of the genus Lilium including L. ledebourii, L. orientalis, L. longiflorum, L. japonicum, L. speciosum, L. concolor, L. nepalense, L. regale, L. oriental hybrid, L. Asiatic hybrid has been reported. The purpose of the current study was to evaluate the effect of different concentrations of BA and NAA on in vitro proliferation of Lilium oriental hybrid ‘Casablanca’ using bulb scale as explant to establish a suitable protocol.Materials and Methods Effect of various concentrations of 6-benzyle adenine (BA; 0, 0.5, 1 and 2 mg l–1) and ɑ-naphtaleneacetic acid (NAA; 0, 0.1, 0.2 and 0.4 mg l–1) were evaluated on in vitro proliferation of L. ‘Oriental’. Bulb scale as explant and MS basal medium as culture medium were used. Activated charcoal was applied to inhibit the browning of the culture medium and explant. The experiments were conducted in completely randomized design (CRD). The 16 treatments were applied, each treatment had 4 replications and each replication had 4 individuals. Therefore, in these experiments, a total of 192 bulbs were used. Traits including total plantlets fresh weight, leaf length, leaf number, bulblet weight, bulblet diameter, bulblet number, survival percentage, root length and root number related to in vitro proliferation were measured. All the statistical analyses were done by using SAS and Tukey’s test. Arcsin software was used for changing percent data.Results and Discussion The interaction effect of BA and NAA was significant for all measured traits. Results showed that the maximum number of bulblet (8.66) and root (5.36) were obtained in culture medium enriched with 0.5 mg l–1 BA together with 0.4 mg l–1 NAA. Culture media supplemented with 0.5 mg l–1 BA together with 0.2 mg l–1 NAA and 1 mg l–1 BA together with 0.1 mg l–1 NAA with induction of 7.33 bulblets per explant were suitable media. The largest number of leaf (4.33) was measured in culture medium containing 1 mg l–1 BA together with 0.1 mg l–1 NAA. The highest bulblet weight was measured in culture medium supplemented with 1 mg l–1 BA along with 0.2 mg l–1 NAA. The greatest survival rate (100%) was observed in medium enriched with 0.5 mg l–1 BA together with 0.1 mg l–1 NAA. Survival rate (90%) in explants treated with 2 mg l–1 BA along with 0.4 mg l–1 NAA was high. Obtained results revealed that the presence of both BA and NAA in culture media for enhancement of most traits is necessary and critical. Plantlets were transferred to a growing medium containing cocopeat, peat moss and perlite in identical proportion for acclimatization following proliferation. Approximately, 90% of regenerated plantlets survived and were morphologically similar to the mother stocks. This study will help the producers and breeders for commercial and improvement purposes. The effective role of the simultaneous presence of both auxin and cytokinin in the culture medium in effective organogenesis was shown in the present study. Similar findings were reported for some lilies such as L. ledebourii (Baker) Bioss., L. longiflorum and L. regale. Auxin was effective in stimulating bulb production and growth of the aerial part of the eastern lily, and its presence along with cytokinin is essential for leaf induction. Some studies have reported similar results. The type and optimal concentration of plant growth regulators (PGRs) in the culture medium for suitable in vitro propagation varies in different species. Genetic variations (species type), differences in the amount of endogenous production of PGRs and their interaction with each other are among some reasons for this difference. The proper ratio of auxin and cytokinin in the culture medium is effective for inducing cell division, cell differentiation, organogenesis and finally for achieving a complete plant. Root production with appropriate quantity and quality leads to the suitable survival of seedlings resulting from the growth of cultured explants under in vitro conditions and adapted plants. Current study showed that the presence of both BA and NAA is better than the presence of one of these two PGRs for induction and growth of root. Some similar findings were reported, however in most studies, the presence of auxin as individual PGR has been found to be more suitable for root induction.
Pomology
Behzad Kaviani
Abstract
Introduction: 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. Biofertilizers are gradually being replaced by chemical fertilizers. Strawberry is a fruit with high nutritional value. ...
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Introduction: 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. Biofertilizers are gradually being replaced by chemical fertilizers. 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. The leaf application of humic acid was effective in increasing the amount of phosphorus, potassium and nitrogen. The amount of potassium and phosphorus in strawberry fruit is more than other elements. Combining some cultivation beds (perlite and composts) and fertilizers such as agricultural waste (rice bran and tea wastes) into soil cultivation beds have an effective role in improving the quantity and quality of plants.Materials and Methods: A pot experiment was conducted to evaluate the effect of foliar application of humic acid and different cultivation beds on nutrition uptake of strawberry. Different concentrations of humic acid (0, 300, 600, and 1000 mg.l−1) were applied as foliar application in two steps (late March and late April) on strawberry cultivated in different beds (usual soil, usual soil + rice bran, perlite, or tea wastes). This study was carried out as two factorial experiment in completely randomized design. Soil nitrogen, phosphorus and potassium, soil pH and electrical conductivity and leaf and fruit nitrogen, phosphorus and potassium content were measured. Measurement of nitrogen, phosphorus and potassium was carried out by Kjehldal, spectrophotometry and flame photometry, respectively.Results and Discussion: The interaction effect of humic acid ×cultivation beds on nitrogen and phosphorus content of leaves and fruits was significant at 1% of probability level and on fruit potassium at 5% of probability level. The interaction of these two factors on leaf potassium was non-significant. The results of comparing the mean comparison of humic acid and cultivation beds on soil elements showed that the highest amount of nitrogen was obtained in the treatment of 600 mg.l−1 humic acid and in the cultivation bed of usual soil+rice bran. The highest amount of phosphorus was obtained in the treatment of 1000 mg.l−1 humic acid and the cultivation bed of usual soil + tea wastes. The highest amount of potassium was obtained in the treatment of 600 mg.l−1 humic acid and in the cultivation bed of usual soil + tea wastes and the lowest one was obtained in the same bed without humic acid. Results showed that the highest potassium content (518 mg.l−1), and phosphorus (4.84 mg.l−1) of fruit were obtained in plants treated with 1000 mg.l−1 humic acid cultivated in usual soil + rice bran. The highest nitrogen content of fruit was obtained in plants cultivated in usual soil +tea wastes. The plants grown in this cultivation bed with humic acid application at 1000 mg.l−1 had maximum content of leaf nitrogen (5.47%). The highest content of leaf potassium (4.50 mg.l−1) and phosphorus (6.32 mg.l−1) were obtained in plants treated with 600 mg.l−1 humic acid in the cultivation beds of usual soil and usual soil + rice bran, respectively. The application of humic acid at 1000 mg.l−1 and using usual soil+rice bran as bed is recommended for strawberries production as potassium, phosphorus and nitrogen are the most important elements for increasing the quality of strawberry fruits , respectively. A positive association has been reported between the use of humic acid and the increase in growth, yield and product quality in strawberries and other plants. Humic acid can improve quantitative and qualitative production of crops by providing more available essential elements and increasing plant resistance to various biological and non-biological stresses.Conclusion: 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, short pot life, and poor quality and environmental pollution. Therefore, organic fertilizers have been recommended. A stimulating effect of humic acid on biomass production and plant growth is to increase the uptake of nitrogen, phosphorus and potassium. Proper cultivation bed plays an important role in the optimal growth and development of plants. According the result of this study, the use of beds containing agricultural waste and foliar application of humic acid increased the growth, yield and quality of strawberry fruit.
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.
