Plant Productions
Year:2017 | Volume:40 | Issue:2 |Papers Count:12

Background and Objectives: Carnation (Dianthus caryophyllus) is one of the most important and consumption cut flowers in the world. Carnation cut flowers are sensitive to microbial contaminations at the stem end or in the vase solutions that make their vase life shorter. Numerous studies have reported that three genera of bacteria are the main bacteria which were recognized in the preservative solution of cut flowers. Nowadays, the finding of new compounds as alternatives to common chemicals is important in postharvest of cut flowers. The aim of this study was to investigate the effects of new compounds including chitosan, thymol and green silver nanoparticles on vase life of cut carnation flowers.Material and Methods: The effects of green silver nanoparticles (25, 50 and 100 mg L-1), thymol (25, 50 and 100 mg L-1) and chitosan (25, 50 and 100 mg L-1) were investigated against of silver nitrate (25, 50 and 100 mg L-1) and control (2% sucrose) on vase life of carnation cut flowers "White Liberty", in this research. All treatments included 2% sucrose. Cut flowers were held in treatments for 24 hours, then replaced with distilled water. The experiment was carried out as completely randomized design with three replications. Evaluated characteristics were vase life, relative fresh weight (on days 2, 3, 4, 7, 9 and 10), solution uptake (on days 1, 2, 3, 4, 7, 8, 9 and 10), ion leakage of petals (on day 11) and chlorophyll contents (on days 2, 4 and 8).Results: Results showed that the effects of different treatments on vase life were significant and thymol 25 (13 days), green silver nanoparticles and chitosan 25 (12.5 days) had the highest vase life in comparison with control. The effects of different treatments on relative fresh weight and solution uptake were significant in the evaluated days. Although, the chlorophyll content of leaves and ion leakage of petals were not significant.Discussions In the present study, it was found that pulse treatment by chitosan, thymol and green silver nanoparticles (25 mg L-1) significantly increased the vase life of cut carnations cv. "White Liberty". The presence of two sections of sucrose as nutrition source and antimicrobial agents seems to be necessary for carnation cut flowers. The antimicrobial effects of these compounds have been demonstrated in several studies. The application of thymol and chitosan as non-toxic compounds in the preservative solutions showed positive prospects for using these in extending carnation cut flowers.

Background and Objectives: Plum as a climacteric fruit has high ethylene production and respiration rate at the ripening stage which is the reason for its short postharvest life. In order to evaluate the effect of oxalic acid treatment on postharvest storage life and maintain qualitative characteristics of plum fruit cv. Santa Rosa, an experiment was performed based on factorial in completely randomized design with two factors, oxalic acid concentration and storage time, in three replications.Material and Methods: Plum fruits were harvested at the commercial harvest stage from a commercial orchard located in Golestan Province, Iran. On the same day, harvested fruits were transported to the laboratory and selected for the uniformity in size, shape and color. The selected fruit samples were distributed into four groups of 60 (each replicate contained 5 fruits). The selected fruits were immersed in oxalic acid solutions (0, 2, 4 and 6 mM) for 3 minutes and after removing the surface moisture at room temperature stored at 4°C and 80% relative humidity. The quantitative and qualitative traits of the fruit were evaluated every two week intervals during 42 days of storage. The obtained data were subjected to analysis of variance using SAS (9.1) software, and LSD values were calculated for the mean comparisons.Results: The results showed that oxalic acid had a significant effect on soluble solids content, titratable acidity, vitamin C, peel anthocyanins and browning index, whilst weight loss, soluble solids content, titratable acidity, vitamin C, fruit flavor index, pH, flesh and peel anthocyanins, total chlorophyll and chlorophyll a, b, total carotenoids, phenols and flavonoids, antioxidant activity, electrolyte leakage and browning index were significantly influenced by storage time. The increment of the oxalic acid concentration led to increase of soluble solids content by the late week 4 of storage. The highest (1.21%) and lowest (0.38%) titratable acidity was recorded for 6 mM oxalic acid in week 2 and 2 mM oxalic acid in week 6 of storage, respectively. At the end of the storage, 6 mM oxalic acid caused to preserve the maximum Vit C content (11.63 mg/100g) compared to control. Oxalic acid had no significance on total phenols and flavonoids; however, the interaction between storage time and oxalic acid had also a significant effect on soluble solids content, titratable acidity, vitamin C, fruit flavor index, peel anthocyanins, phenols, flavonoids and browning index. The weight loss reached 9.96% by late week 6. The electrolyte leakage percent and browning index increased during storage period and the minimum browning index without any significant difference was observed in 2 mM (41.11%) and 4 mM (43.89%) oxalic acid treatments.Discussions: In conclusion, oxalic acid significantly increased titratable acidity, vitamin C, plum peel anthocyanins and soluble solids compared to the control. The treated fruits had a lower browning index than the control. As a whole, regarding the results of this research, post-harvest application of 4 mM oxalic acid treatment could be used to maintain plum fruit qualitative properties and increase the time of storage.

Background and Objectives: Pomegranate is classified as a non-climacteric fruit, so it is considered as insensitive to ethylene.However, in some other non-climacteric fruit it has been shown that ethylene accelerates senescence or increase chilling injury symptoms during postharvest life. In this study, to determine the sensitiveness of pomegranate fruit to ethylene, the effects of ethylene and 1-MCP (as an ethylene inhibitor material) treatments were investigated on the pomegranate storability.Material and Methods: Pomegranate fruit cv. 'Malase Yousef Khani' was harvested at the ripening stage (full aril coloring) from an orchard near Saveh city, and treated followingtreatments; 2 mL/L ethylene for 48 hours, 1 mL/L 1-MCP for 24 hours, and 2 mL/L 1-MCP for 24 hours as well as a combination of 2 mL/L 1-MCP and mL/L ethylene treatments. Fruit without any treatment was put as control. The treatments were applied inside the polyethylene container. Then the treated fruits were stored at 4°C and 90% RH for up to 3 month. The fruits were removed from storage in 1, 2 and 3 months of storage and after 3 days keeping at room temperature as shelf life was analyzed. The experiment was conducted as a factorial based on a completely randomized design with 3 replications at Shahed University in 2016.Results: Results showed that ethylene treated fruits, as compared to 1-MCP treated fruit (even in presence of ethylene in combination treatment) had less fruit and aril marketability, as well as less firmness, ion leakage, total phenol content and antioxidant capacity, whilst this fruit had more weight loss than 1-MCP treated fruits. Ethylene treated fruit had also less fruit and aril marketability, and less antioxidant capacity than control fruit. The control fruit had less fruit and aril marketability, ion leakage, total phenol content and antioxidant capacity than 1-MCP fruits.Discussions: According to these results, pomegranate fruit was sensitive to ethylene and its postharvest loss, such as chilling injury symptoms, electro leakage, and antioxidants reduction was accelerated by presence of ethylene around the fruit. On the other hand, since in the most measured characteristics, control fruit had a lower quality than 1-MCP treated fruit, it seems that pomegranate is very sensitive to ethylene and even low level of internal ethylene is enough to accelerate the postharvest loss of this fruit. Therefore, removal of ethylene from the pomegranate storage, or using the anti ethylene materials such as 1-MCP can be effective in increasing posthrevst life of pomegranate fruit.

Background and Objectives: Seed deterioration is a natural phenomenon that occurs in all seeds and leads to gradual decline of seed viability during storage. However, the rate of seeds age depends upon their physiological status, genetic constitution and storage conditions. The lipid peroxidation through the production of free radical plays an important role in the loss of seed viability during seed storage.Material and Methods: In order to investigate the effect of deterioration on germination indices and enzymes activity of the flax oil seed, a factorial experiment was conducted based on a Completely Randomized Design with four replications in the seed laboratory of Yasouj University in 2015. The factors included 4 levels of temperature (15, 25, 35 and 45°C) and moisture content (5, 9, 13 and 17%).With relation intended seed moisture, Hampton and Teckrony (1995) was calculated. After determining the moisture content of the seeds in envelopes of aluminum foil was placed, then the amount of water the need added and to ensure that the packaging and moisture exchange with the outside world for 24 hours at 15 °C were identical to the seed moisture and then for 6 months in storage conditions at temperatures of 15, 25, 35 and 45°C were kept.Results: Analysis of variance showed that the single effects including temperature and seed moisture content experimental treatments for traits including germination percentage, germination rate, seedling vigor index (weight), activity enzymes antioxidant catalase, superoxide dismutase and ascorbate peroxidase, soluble proteins, electrical conductivity and oil percentage were significant (P£0.01). Also, the interaction temperature and seed moisture content of all treatments except for enzyme, activity of superoxide dismutase and ascorbate peroxidase were significant (P£0.01) but were significant (P£0.05) for the activity of superoxide dismutase and ascorbate peroxidase. The results showed that with increasing temperature and moisture content, all the physiological and biochemical traits, except for electrical conductivity, decreased. The decrease in germination was also associated with a decrease in the activity of antioxidant catalase, superoxide dismutase and ascorbate peroxidase and as a result the antioxidant system was not sufficient to protect seeds against free radical damage. With the increase in reactive oxygen species, lipids peroxidation increased, probably due to the destruction of cell membranes, increased electrical conductivity seed the negative correlation between the electrical conductivity and the activity of the enzymes antioxidant indicator of the issue.Discussions: Thus, oil flax seed deterioration was closely related to decrease in the activities of free radical detoxifying enzymes and increased lipid peroxidation. In general, the best flax seed storage condition is at 15°C and 5 percent moisture content.

Background and Objectives: Postharvest diseases are one of the major causes of storage losses of mango. The incidence of postharvest diseases can affect the quality and limits the shelf life of the horticultural fresh products. Generally, there is a great interest in using essential oils (EOs) as biological control to increasing shelf life of fruits. Mango is one of the most important tropical fruits. The aim of this study was to evaluate in vivo effectiveness of Artemisia persica and Rosmarinus officinalis essential oils against Aspergillus niger, which are one of the most important postharvest diseases of mango.Material and Methods: Inoculation of artificial fungal was done at room temperature. One day after inoculation, fruits were treated with different concentrations of EOs. The fruits were placed into boxes and kept in 25°C for three weeks. Then decay, weight loss, firmness, ascorbic acid and values of surface color were determined during storage. Fruits surface color was measured using a chromameter (CR 400, Minolta) which provided (CIE L*, a*, and b*). Firmness values were measured by using a texture analyzer.Results: Results showed that all treatments had significant effects in preventing fruits decay during storage. Rosemary essential oil at low concentration (500 ml/l)(13.3%) significantly reduced deterioration of mango fruits, followed by Artemisa persica (1000 ml/l) (12%). Quality of fruits was also affected by essential oil. Fruit treated by Rosmarinus officinalis showed the highest firmness (3.7 kg/cm2) rather than other treatments. Different treatments showed more firmness rather than control and different concentrations of treatment did not show any significant difference.Discussions: Modifications induced by EOs might be due to theirs components interactions with cell wall synthesis, which affects fungal growth and morphology. Moreover, the presence of an aromatic nucleus and one hydroxyl group is important for their antimicrobial activity. Some reported that efficacy of plant EOs depends on their composition.

Background and Objectives: In recent years, the increase in so-called phenomenon of widespread dust has adversely affected most of agricultural products such as date palm. This study was conducted in two growing seasons of 2014 and 2015 in order to evaluate the effect of combined treatments including dust, rain and pollination on fruit set, parthenocarpic fruit and fruit abscission of 8-year old 'Estamaran' ('Sayer') date palm cultivar in the Date Palm Research Institute Collection Orchard located in Ahwaz. In addition, dust sediment manner on the flower and stigmatic surface in the simulated environment at the laboratory were studied.Material and Methods: In each combined treatments that applied in the orchard, all bunches of experimental trees were treated as replications. At the laboratory, simulated operation was done by placing the flowers under binocular camera. A soft brush was used for dusting and pollination on the stigma and a manual hand spray for misting. A month after treatment, traits such as fruit set, parthenocarpic fruit and abscission percentage and dust sedimentation manner on the flower and stigma were studied and monitored. The data were statistically analyzed using MINITAB17 software.Results: Results showed that treatments had significant effects on the studied traits. The maximum fruit set was obtained from pollination (66.11%) and the minimum fruit set was recorded in non-pollinated treatment (0.5%). For other applied treatments, in spite of pollination, existence of one or two other factors and their operation order had different effects on fruit set. Combined treatments that included dust caused significant reduction in fruit set and led to the increase in fruit abscission. The maximum parthenocarpic fruit was observed in non-pollinated treatment (23.38%) with the significant difference in comparison to other treatments and the minimum parthenocarpic fruit was produced by combined dust, rain and pollination treatment (0.48%). In addition, maximum abscission was observed in the combined dust, rain and pollination treatment (83.82%) and the minimum abscission was observed in pollination treatment (32.88%). The data obtained for simulated operation at the laboratory were in agreement with field experiment results. The formation of dust insulator layer on the stigmatic surface inhibited most of the pollen grains for direct contact to the stigmatic surface. The obtained results from this research showed the negative impact of the dust on fruit set. Based on these data, supplemental research on repeating pollination after the dust storm during date palm pollination is recommended.Discussions: Date palm is a dioecious plant and pollen access to flower stigma is necessary for its proper fruit set. Based on the obtained results, dust can form a blockage layer on the stigma and could prevent the germination of pollen grains on the stigma and consequently penetration of pollen tube into the style and further failure of the proper fertilization and fruit set. Therefore, after dust and storms, repeated pollination should be done for suitable pollen germination, pollen tube growth in the style and further proper date palm fruit set.

Background and Objectives: Wheat (Triticum aestivum L.) may be exposed to different stress conditions that influence its productivity. One way to confer tolerance to the drought's effects and stimulate plant productivity is the action of a group of bacteria capable of making association with plants, known as Plant Growth Promoter Rhizobacteria (PGPR). It was demonstrated that the PGPR can benefit the plants in several ways: synthesizing some phytohormones, siderophores, biological nitrogen fixation, inducing systemic resistance etc. The objective of this work was to evaluate the physiological responses of two wheat cultivars to PGPR under rain fed conditions.Material and Methods: To evaluate the effect of PGPRs on physiological characteristics of two wheat cultivars a factorial experiment in a randomized complete block design with three replications was carried out under rainfed conditions in Germi region. Experimental factors included two wheat cultivars (Atila and Zagros) and five bacteria (Pseudomonas putida strain R168, R159, R112, Azosprillium lipoferumstrain A21 and Azotobacter chroococcum strain E5) as well as a control treatment. The parameters measured included: Carbonil Protein, chlorophyll, Soluble Sugar, Cell Membrane Stability, tillers in shoot, 1000-grain weight, grains number per spike, Shoot dry weight and gain yield.Results: Results showed that the highest amount of chlorophyll and soluble sugar in leaf in Zagros cultivar was obtained from bacteria Pseudomonas strains R159 and Azotobacter, respectively, but in Attila cultivar Pseudomonas strains R112 showed the highest chlorophyll and leaf sugar. Most of the membrane stability and the highest amount of protein carbonil was obtained from Pseudomonas strains R112 and control, respectively. In the Zagros cultivar, the Pseudomonas bacteria, with 3130 kg/ha seed yield than other bacteria were superior and also showed the highest 1000 seed weight but in Attila cultivar although bacterial treatments had a higher seed yield than control, but no significant difference was observed between Azosprillium with R112 and R159 strains.Discussions: The amounts of Cell Membrane Stability, grain number per spike, tillers in shoot, 1000-grain weight and shoot dry weigh increased in the presence of PGPRs for both cultivars, probably by action of ACC deaminase activity. The chlorophyll and soluble sugar increased in the presence of PGPRs comparing controls for both cultivars. The protein carbonil was fewer only when bacteria were present compared to controls. It is possible to conclude that the association of Pseudomonas putidastrains R112 is more effective and indicates the reduction of ethylene. These data corroborate with the literature where plant vs. bacteria interaction is genotype and strain dependent. Finally, Zagros cultivar showed better response to bacterial inoculotion and for rainfed conditoin of Germi area cultivation of Zagros cultivar as well as bacteria Pseudomonas strains R112 inoculation is recommended for maximum seed yield.

Background and Objectives: Apple belongs to Rosaceae specious and its scientific name is Malus Pumila L. Today over 35 specious of apple has been known in the world. According to the Food and Agricultural Organization (FAO), regarding the Apple planting area, China ranks first and Russia, India and Ukraine place second and third respectively. Considering the fact that Malling rootstock has different effects on quality and quantity characteristics of different specious and show different reactions in different densities, this experiment was done in order to determine the apple cultivar ' Red Delicious' in Meshginshahr region.Material and Methods: This experiment was done in split plot based on Random Complete Block Design in three replications in two years in Meshginshahr Agricultural and Natural Resources Research Station.The experimental treatments were D=planting distance in two levels (d1=2´4 and d2=3´4) meters as the main plot, and R=growing rootstocks in three levels (r1=MM106, r2=M9 and r3=M26) as the secondary plot. Each treatment had 4 plants of apple 'Red Delicious' crossbred on their growing branches. The total numbers of plants used were 72. The qualitative and quantitative characteristics such as flower density, yield, fruit size, color, acidity, solvable solid materials and dry matter weight were measured separately for each treatment.Results: Analysis of variances showed significant differences between years in terms of yield and flower density; between the planting distances in terms of yield, fruit size and soluble solids concentration and flower density; between rootstocks in terms of yield, fruit size, flower density and dry matter; and significant differences in yields between interactions of the planting distances´rootstocks, year´planting distances´rootstocks. Apple Cultivar 'Red Delicious' grafted on M9 rootstock in planting distances of 2´4 m with 9.367 tons per hectare had the highest yield and was placed in group. Analysis of average effect of rootstock in fruit production showed that ' Red Delicious' on M9 rootstocks produced the biggest fruit and had the highest density. Fruit size, flower density on tree and soluble solids concentration in the planting at a distance of 3´4 m were greater than that in 2´4 m.Discussions: Year and planting distance interplay on yield had a significant effect in a way that the amounts of yield on all rootstocks were the highest during the two years of experiment. Planting distance had a significant effect on solvable solid matter of the cultivar apple red delicious at the probability level of 1 percent. Other factors did not have any significant effect on solvable solid matter acidity. In more planting distances, the trees can get more sun light and nutrient materials, hence their solvable solid matter increases.

Background and Objectives: Blackberry cannot be conserved for long time due to its short post-harvest shelf life and rapid perishability. Recently, using small plastic containers has become popular that but is unfortunately non-biodegradable and incompatible with the environment so these materials are dangerous for the environment. But using biodegradable packages which are made up by natural materials like starch, corn, potato and wheat can be a suitable substitution. This research aimed to evaluate optimum conditions including temperature and container material for increasing summer wild blackberry shelf life.Material and Methods: With the aim of evaluating summer wild blackberry optimum storage conditions, its fruits were compared via three levels of temperature (0, 4 and 25°C) and two kinds of containers (biodegradable and non-biodegradable) during 14 days. Different characteristics comprising visual quality (fruit weight, fruit weight loss and market acceptance), edible quality (TSS, pH, TA, TSS/TA, flavor and taste) and health value (total antioxidant activity, total phenol content, total flavonoid content and total anthocyanin) were evaluated.Results The obtained results showed fruit weight loos. During postharvest maintenance in all treatments, the highest fruit weight recorded on the first day and after that decreased significantly. In addition to fruit weight, length, width, flavor, taste and market acceptance of fruit decreased during storage, significantly. Visual quality of fruits packed in polystyrene container was better than bio based one. Total soluble solids of blackberries stored in biodegradable package were significantly higher than non-biodegradable container. Inhibitory percentage of DPPH radicals in all treatments showed powerful antioxidant properties of blackberry. The highest phenol content (62.33 gGalicacid/ g fruit juice) of fruits was recorded on the 3rd day at 4°C in polystyrene container. The lowest amount of total phenol in the same temperature was observed after 8 days storage in biodegradable container. In both containers, the temperature of 0°C showed less decrease of flavonoid content. During the experiment anthocyanin content decreased generally but on the 8 th and 14 th days in polystyrene container and 0°C, its content increased from 224.99 on the first day at 0°C to 57.89 and 90.3 mg Cyanidin/Lit fruit juice in both containers types on the 14th day, significantly.Discussions: Water loss due to transpiration and respiration is the main reason for weight loss during postharvest period. Because of this, using Nano particles in container materials around the fruits to control water exchange can reduce weight loss and influence different fruit characteristics as well. The positive effect of the 0°C temperature on blackberry shelf life was significant. Using a biodegradable package despite its environmental importance showed less efficiency for increasing blackberry postharvest life in comparison with a plastic package and requires further research.

Background and Objectives: Atmospheric dust is one of the pollutants that is considered the biggest environmental problem in different parts of the world. Dust can affect, either directly or indirectly, both plants and crops. The direct impact is on critical activities such as plant photosynthesis, evapotranspiration, stomata conductance, pigments, leaf temperature and breathing. The indirect effect may influence reduction of the fruit quality and yield. This study aims at investigating the adverse effects of dust on grape vineyard in Malayer, Hamedan Province, Iran.Material and Methods: The experiment was conducted in randomized completely block design for evaluation of the effects of dust on White Seedless Grape (Vitisvinifera L.) in the Grape Research Institute, Malayer, on 27 vines during 2014-2015 year. The first treatment was dust (9 plants); soil samples were collected from Khuzestan province and after preparation was applied on the plant in four growth stages using mechanical devices; in the second treatment, solution treatment, dusts were washed with water and di octyl; the third one was control (9 plants).Chlorophyll a and b, carotenoids, vegetativetraits such as length of cane, length of leaf, leaf area, length of peduncle, internodes and reproductive traits such as fruit set, number of berry and number of bunch, length of bunch, number of berries in bunch, weight of berry and brix of berry were measured.Results: The results revealed that leaf pigments reduction was caused by deposition of dust on leaf surface and differences between treatments were significant at 5% probablity level. The vegetative traits viz. length of peduncle, internodes and leaf area were small in the dust treatment and the difference between treatments was significant. Length of cane in the second stage was significant and the longest canes were in the solution treatment. Fruit set, number of berries and number of bunch were reduced in dust treatment and a significant difference was observed between treatments. In addition, control and solution treatments were in one class. Moreover, sugar in a single grape was decreased up to 7 % in dust as compared to other treatments.Discussions: Dust treatment had more effect on b chlorophyll in the first, the third and the fourth growth stages of grape as compared to a chlorophyll and Carotenoid. In addition, the difference between the means was significant at 5 % level. Previous studies showed that the leaf dust accumulation decreased pigment content of plant. roadside plant could be damaged by dust and had shorter length of cane. The rate of fruit set in control, dust and solution treatments was 36%, 21% and 33%, respectively. Moreover, the percentage of brix in control, dust and solution treatments, was 20%, 7% and 15%, respectively. The research revealed that dust could reduce photosynthesis and consequently the amount of brix in grapes which was in agreement with our study.