Medicinal Plants
Mehdi Moradi; Bahram Abedi; Hossein Arouiee; Sasan Aliniaeifard; Kamal Ghasemi Bezdi
Abstract
Background and objectives
Light is the main environmental factor for plant growth and development. Different attributes of light such as intensity, quality and duration affect plant growth and productivity. Light spectrum of growing environment is a determinant factor for plant growth ...
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Background and objectives
Light is the main environmental factor for plant growth and development. Different attributes of light such as intensity, quality and duration affect plant growth and productivity. Light spectrum of growing environment is a determinant factor for plant growth and photosynthesis. The photosynthetic reactions are directly affected by various light parameters including its spectrum and intensity. Photosystem I and II (PSI and PSII) in the electron transport chain of photosynthetic apparatus are involved in converting solar energy to chemical compounds in plants. It has been found that the PSII is sensitive to light quality. Using The OJIP test, we can investigate the efficiency of various biological phases of the electron transport system. Light sources such as metal-halide, fluorescent, high-pressure sodium, neon lamps and light-emitting diode (LED) can be used for production of plants in closed environments instead of sunlight. Manipulation of the light spectrum of the lamps could trigger potential benefits by enhancing plant growth. Nowadays, by using the LED technology, it is possible to study the physiological effect of different light spectra for optimization of growth conditions and for increase the production of plants in controlled environments. This research was conducted to investigate photosynthetic apparatus, growth parameters, stomatal characteristics, transpiration rate and essential oil content of Salvia officinalis under different light spectra.
Materials and Methods
In this study, the effects of different light spectra were implemented and performed as a pot experiment using soilless media in the plant growth chamber based on a completely randomized design with 6 lighting spectra including White, Blue, Red and three combinations of R and B lights (R30:B70, R50:B50 and R70:B30) with three replications. The light intensity in all growth chambers was adjusted to photosynthetic photon flux density (PPFD) of 250 ±10 μmol m-2s-1 and light spectrum were monitored using a sekonic light meter (Sekonic C-7000, Japan). Growth condition was set at 14/10 h day/night cycles, 25/22oC day/night temperatures and 40% relative humidity. Three month following plant growth under different light spectra, the plants were evaluated for their growth parameters, stomatal characteristics (stomatal length, stomatal width, pore length or aperture) transpiration rate (E), relative water content (RWC), photosynthetic apparatus (evaluation of OJIP) and essential oil content. Data analysis of variance (ANOVA) was performed using IBM SAS software (Version 9.1) and the differences between means were assessed using Duncan’s multiple range tests at p≤ 0.05.
Results
The results showed that the stomata characteristics, photosynthetic performance, growth characteristics and essential oil content of Salvia officinalis were affected by different light spectra. Increasing the ratio of red light especially combined Red and Blue lights (R70:B30) led to the improvement of growth characteristics. Transient induction of chlorophyll fluorescence showed that the highest fluorescence intensities at all OJIP steps were detected in Red light. The lowest Fv/F0 and Fv/Fm were obtained in plants grown under Red light. Occurrence of leaf epinasty and decrease in Fv/Fm indicative of phenomenon of red light syndrome in the plants under Red treatment. Red light caused a reduction in performance index per absorbed light efficiency of (PIABS) and increase in quantum energy dissipation (ΦD0), light absorption (ABS/RC) and electron trapping (TR0/RC) per reaction center. The highest Fv/F0, Fv/Fm and PIABS were obtained under combination of Red and Rlue light. The highest ΦE0 was also detected in combination of Red and Blue light. The narrow and large stomatal apertures were detected under Red and Blue light, respectively. The highest transpiration rate was achieved in plants grown under Blue light LED. Increasing the ratio of Red light resulted in reduction in transpiration rate and improvement of leaf capacity to control water loss via reducing the opening of stomata. The highest amount of essential oil (1/75% v/w) was achieved in plants exposed to combination of Red:Blue light spectra (R70:B30).
Conclusion
light spectrum during plant growth can change plant metabolism, LED can be used in favor of producing good-quality food in controlled environment agriculture due to their ease of application, waveband manipulation and limited heat production. Our result showed that photosynthetic apparatus, growth parameters, stomatal characteristics, transpiration rate, relative water content and essential oil content of plants were considerably influenced by light spectra. Using OJIP test confirmed that plants grown under monochromatic Red and Blue lights were less efficient to successfully transfer the excitons and most of the absorbed energy by the photosystems was dissipated as heat. In conclusion, combined Red and Blue lights (especially R70:B30) caused favorable growth, photosynthetic functionality and maximum essential oil content of Salvia officinalis. Therefore, combination of R and B lights (R70:B30) should be considered for production of Salvia officinalis under artificial light systems during commercial controlled environment production of plants.
Zahra Falahi; Sasan Aliniaeifard; Mostafa Arab; Shirin Dianati deylami
Abstract
Introduction: Postharvest handling of tropical flowers is usually difficult due to their sensitivity to cold temperatures. Anthurium(Anthurium andraeanum)is a tropical plant used in ornamental industry for its beautiful spathe and leaves. It can be produced in wide ranges of climates; in locations far ...
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Introduction: Postharvest handling of tropical flowers is usually difficult due to their sensitivity to cold temperatures. Anthurium(Anthurium andraeanum)is a tropical plant used in ornamental industry for its beautiful spathe and leaves. It can be produced in wide ranges of climates; in locations far away from their original habitats in greenhouses. Although, anthurium has long vase life compared to other cut flowers, postharvest exposure to cold temperatures makes some restrictions on its desirable vase life. This study aimed to investigate the effects of different light spectra on postharvest performance of anthurium cut flowers. Materials and Methods: Cut flowers of Anthurium andraeanum cultivars with red ('Calore') and white ('Angel') spathes were obtained from a commercial anthurium greenhouse on the morning. Anthurium cut flowers were harvested when 40-50% of the spadix true flowers were fully opened. Each flower was placed in closed flasks containing 500 mL water. Sixty flasks with cut flowers (30 cut flowers from each cultivar) were placed into chambers with exactly similar conditions but with different light spectra including white (W), blue (B), red (R) and 70% R+30% B (RB) provided by LED production modules and darkness. Each flower under light spectra was inspected and the vase life of the all flowers, change in spathe angel, spathe area, maximum quantum yield of photosystem II (Fv/Fm) and fluorescence decline ratio (RFD) were measured during 14 days exposure to 4 °C storage. Results and Discussion: Spathe 'angel' seven and 14 days following exposure to cold storage was dramatically increased in B light while the lowest changes were observed in R light of the both cultivars. Vase life of anthurium cut flowers were significantly (P≤0.01) influenced by the interaction between light spectra and cultivars. Among the light spectra, the longest vase life were observed in spathes exposed to R light in both cultivars. In 'Angel', exposure to B light dramatically shortened the vase life of anthurium cut flowers in comparison with the other light spectra. A positive relationship was detected between spathe area and vase life of cut flowers, while the relationship between spathe 'angel' and vase life was negative. No photosynthetic activity was detected on the spathe of anthurium, but the peduncle of anthurium showed the photosynthetic activity. The highest Fv/Fm and RFD values were detected in darkness and the lowest values for Fv/Fm and RFD were observed in R and RB-exposed spathes. No relationships was observed between the photosynthetic activities and the vase life of anthurium cut flowers. Although there are some reports confirmed the importance of plant growth under different light spectra on its postharvest quality, there is no report regarding the effects of light spectra on the quality of cut flowers in postharvest stage. Similar to anthurium, some reports indicated that there is no relationship between the photosynthesis and the quality of harvested products. Conclusion: Exposure of anthurium cut flowers to different light spectra resulted in alterations of morphology and quality during exposure to low temperatures. B spectrum had strong negative effects on the morphology and quality of anthurium cut flowers, while exposure to R light resulted in improvement of quality of anthurium cut flowers with less negative effects on their morphology. Spathe of anthurium had no photosynthetic activity, while its peduncle showed the photosynthetic activity. There were significant relationships between morphology and vase life of anthurium cut flowers, while no relationships were found between photosynthetic activity and their vase life. In conclusion, lighting environment during postharvest of anthurium cut flowers should be take into account for keeping their quality under low temperature conditions. Red light spectrum was introduced as the best light treatment to reduce chilling injury, increase the vase life and maintain the quality of anthurium cut flowers in both cultivars.
Mehdi Bagheri; Iman Roohollahi; Sasan Aliniaeifard
Abstract
Introduction: Management of rose plant structure plays an important role in flower production throughout the year and determines the amount of rose plant life span and influence plant development and quality of cut flowers (length, diameter and weight). In the past, roses were planted in a row, and their ...
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Introduction: Management of rose plant structure plays an important role in flower production throughout the year and determines the amount of rose plant life span and influence plant development and quality of cut flowers (length, diameter and weight). In the past, roses were planted in a row, and their structure was in the form of long vertical hedges, with annual pruning often involving, disbudding and pinching. Rose growers tend to bend non-producing shoots to increase light absorption and build more photosynthetic assimilates and increases the quality of the produced cut flowers. In this study was investigated for proper management of pruning of cut rose bud with an emphasis on degrees of shoot bending. Materials and Methods: The cutting's media were prepared from a combination of Cocopeat and Perlite at 50% equilibrium. The cuttings were planted in two-meter-long boxes 18 cm apart. From day 4, nutrient solution was injected into the substrates. Nutrient solution volume per plant was 550 ml per day, which was injected 11 times into the culture medium. In order to select the best plant structure architecture for producing the highest quality of the cut flowers, a factorial experiment was conducted based on a completely randomized design with two shoot pruning and bending treatments. During the bending process to increase the accuracy of the experiment, two bent shoots were counted for all cuttings, six days after bending treatment the dormant buds were activated in the primitive part of the stem and began to grow. Pruning of the buds was done in two levels of 50% pruning and without pruning. 45 days after bud removal, flower shoots were harvested, and samples were transferred to the laboratory for post-harvest evaluation. Chlorophyll and carbohydrate concentration, photosynthesis index, physiological, morphological and photosynthetic parameters were measured as well as vase life trait. Results and Discussion: Pruning of buds at 1% probability level was important on carbohydrate content and bending at 5% probability level on carbohydrate and vase life. Furthermore, the interaction between the two pruning treatment and bending at 1% probability level was significant on the carbohydrate content and vase life. In general, it could be concluded that by bending the shoots, the light penetrates into the plant structure, which ultimately increased photosynthesis and the amount of carbohydrates in flower buds. It could be concluded from the observations that bent shoots with appropriate angles could consume their carbohydrates for bud flower production. In other words, bending branches plays the role of factories which task is to deliver the photosynthetic production in the bending branches to the flower branches that are the most important consumer. The results showed that bending of branches (45 and 90 degree), with increasing light absorption and making more photosynthetic assimilates and changing their flow from bent branches to shoots, caused their proper growth and 30% increasing in the fresh and dry weight traits. The diameter of the bud and the length of the flower shoot increased post-harvest quality of the cut flower. Furthermore, the interaction of bud pruning and bending had a positive effect on carbohydrate content of flower shoots. On the other hand, the vase life were evaluated, which showed that the bending 45 degree had the highest vase life (22.5) and 120 degree had the lowest vase life. At treatment 120 degree (lowest postharvest survival), non-pruned treatments showed longer vase life (16 days) and lower pruned treatments after harvest (13.5 days). It also showed the highest fresh weight, dry weight, peduncle diameter and flower length are 45 degree. No significant difference was observed in the photosynthesis rate of a bent branch near the bed and vertical branches above the bed. By bending the branch at the right angle, it made the bent light branch more efficiently utilized and maintained its photosynthetic rate, although bending stress, at the high levels and in the manufacture of carbohydrates and other products. Photosynthesis for helping the plant eventually gained more carbohydrates from its vertical branches (flowering), and increasing carbohydrates will lead to a relative increase in quality, bud diameter and flower length and eventually vase life of the cut flower. Conclusion: The results of the bending treatment showed that the accuracy of the bending time and degree of 45° and 90° subsequently resulted in an increase in the quality of production.
Hassan Farhadi; Mohammad Mehdi Sharifani; Mehdi Alizadeh; Hossein Hokmabadi; Sasan Aliniaeifard
Abstract
Introduction: Agriculture of Iran is known worldwide for its pistachio (Pistacia vera L.) and is one of the most important non-oil exports. Therefore, attempts to improve the yield can be one of the primary goals in the pistachio industry in Iran. Due to the drought problem in Iran, increasing the cultivation ...
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Introduction: Agriculture of Iran is known worldwide for its pistachio (Pistacia vera L.) and is one of the most important non-oil exports. Therefore, attempts to improve the yield can be one of the primary goals in the pistachio industry in Iran. Due to the drought problem in Iran, increasing the cultivation area to increase production may not be a good option. Therefore, the purpose of this study was to compare the drought tolerance of different pistachio seedlings from open pollination and pollinated with domestic species pollen and controlled crosses using integerrima pollen in order to find the most tolerant genotypes.
Materials and Methods:
The first step: Controlled pollination and hybrid seed production In order to produce hybrid seeds, a controlled pollination using integerrima pollen grains at Razavi Pistachio Research Institute was conducted for five cultivars; Ahmad Aghaei, Akbari, Sorkheh Hosseini, Garmeh and Fandoghi. Each replication had a tree and from each tree, seven branches were selected that had at least three to four flower buds and four branches from it for controlled pollination, two branches for open pollination and a branch was considered for negative control. Before the flower clusters were fully opened, 70% alcohol was sprayed on the branches to prevent the possibility of unwanted pollen. In order to ensure controlled pollination, in the bud swelling stage, the branches were isolated by double-layered bags measuring 30 × 45 cm. Pollen was collected from the Arzooieh area of Kerman province to select the male parent of integerrima. Then, a combination of flour and integerrima pollen (1:1 ratio) was injected into the insulating bags and pollination was performed. In late summer, hybrid seeds were harvested.
The second stage: Drought resistance test of hybrids obtained from first step The experiment was conducted as factorial based on a Completely Randomized Design with four replications at the research greenhouse located in Gorgan University of Agricultural Sciences and Natural Resources during 2019-2020. The treatments were consisted of ten pistachio genotypes; Ahmad Aghaei, Akbari, Sorkheh Hosseini, Garmeh, Fandoghi and (hybrids between integerrima as the pollinizer and genotypes of Ahmad Aghaie, Akbari, Sorkheh Hosseini, Garmeh and Fandoghi were applied as the maternal parent and three levels of drought including control (field capacity), mild stress (65% of field capacity) and severe stress (30% of field capacity) were applied on 3 months old seedlings for 84 days. Seeds obtained from free and controlled pollination were planted in pots with a diameter of 33 cm and a height of 35 cm on April 6, 2017. Three seeds were planted in each experimental unit, and after planting and ensuring establishment, the number of plants in the pot was reduced to the final level of one in each pot. Each replication was consisted of four experimental units or four pots, and each pot was contained a plant. At the end of the experiment, growth and physiological parameters were measured. Statistical analysis of the results was performed using SAS 9.1 software.
Results and Discussion: Results of statistical analysis showed drought stress had a significant effect on leaf number, stem length, root length, leaf relative water content, electrolyte leakage, chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, and leaf and root proline content. With increasing drought levels, all traits except root length, electrolyte leakage and proline content were reduced in comparison with control. Sorkheh Hosseini × integerrima, Ahmad Aghaei × integerrima, Akbari × integerrima interactions and genotypes of fandoghi and fandoghi × integerrima interaction were superior in the most of traits by drought, respectively. Based on the results it seems hybrids of Sorkhe Hosseini × integerrima, Ahmad Aghaei × integerrima and Akbari× integerrima crosses will be used as genotypes with dry-tolerant genes to modify cultivars in arid regions.
