Growing vegetables
Mohammad Zare Mehrjerdi; Nasim Safari; Seyyedeh Mahdiyeh Kharrazi; Azadeh Khadem; Ahmad Sharifi
Abstract
Introduction In addition to providing the necessary energy for photosynthesis, light controls many plant metabolic processes. Nowadays, the use of supplemental light significantly improves the quality of the food product in the conditions of lack of natural light in the autumn and winter seasons. ...
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Introduction In addition to providing the necessary energy for photosynthesis, light controls many plant metabolic processes. Nowadays, the use of supplemental light significantly improves the quality of the food product in the conditions of lack of natural light in the autumn and winter seasons. Light-emitting diodes have been proposed as alternative light sources in controlled agricultural environments. These lamps are the first light sources with the ability to control the light spectrum. Therefore, by controlling the light spectrum and matching the wavelength of LED lamps with the photoreceptors of the plant, the performance and quality of the plant is improved. Cucumber is one of the most important greenhouse plants and its seedlings are generally produced during the autumn and winter seasons, when natural light is relatively low; therefore, the use of supplementary light is required. The use of artificial light sources in fully controlled conditions can change and improve the growth conditions of the plant and also improve its quantitative and qualitative traits. In this research, the aim was to investigate the effect of different qualities of light on the morphophysiological indicators of cucumber seedlings. Materials and Methods This research was performed at the Horticultural Plants Biotechnology Department, Industrial Biotechnology Research Institute of Khorasan Razavi. First, the seeds of the cucumber plant (Cucumis sativus L. var. Officer) were planted in a planting tray, and placed under the light panel with different light treatments. The experimental treatments included four light qualities including white light (6000-6500K) blue light (460-470 nm), red light (625 nm) and combined light (blue + red + white). The amount of photosynthetic photon flux was considered the same in all light treatments, which was equal to 2.75 µol m-2 s-1 CO2 assimilation. Thirty days after planting of seeds, the growth of plants were measured in three stages every 10 days. In each stage, 4 plant samples were selected and then plant height, leaf area, fresh and dry weight of shoots and roots, plant dry matter index and leaf chlorophyll content were measured. Data preparation was done in Excel software, data analysis was done using JMP-8 software and treatment averages were compared using LSD test at 5% probability level. Results and DiscussionThe results of the experiments showed that the quality of light was significantly effective on the growth indicators of Cucumber plants. Plant height in red light and blue light treatments compared to the white light and combined light (red+blue+white with the same intensity) treatments, increased by more than 130% and 60%, respectively. The lowest height was observed in plants grown under combined light, 9 and 14.25 cm after 40 and 50 days of cultivation respectively. The exposure of cucumber seedlings to the red and combined lights recorded the highest and the lowest leaf area in the plants, 618.65 and 377.26 cm2 respectively. Also white light significantly improved the dry weight of the roots. It is worth to mention that the highest plant fresh weight was observed in blue and white lights, 20.9 and 19.5 g respectively. For parameters such as dry weight, dry matter index, and pigment content, the light treatments did not exert a significant effect. However, the utilization of red and blue light, both individually and in combination, positively impacted plant growth. Notably, exposure to red light alone led to a significant increase in leaf surface area, root dry weight, and plant height compared to other light conditions. Previous studies have indicated that red light enhances leaf area, stem length, and fresh weight of plants. Leaves play a critical role in plant photosynthesis and overall growth. Therefore, increasing the leaf area in the plant increases the amount of photosynthesis, growth and development of the plant. In this study, with the increases of the leaf area in the plant and the subsequent increases in the amount of photosynthesis, allocation of dry mater to root increased. The results of the research has been shown that the combination of blue and red wavelengths in pepper, tomato and cucumber seedlings is effective in stimulating plant growth and improving the morphological characteristics under controlled conditions. Blue and red lights can increase the proton flow rate of epidermal cells through the separation mechanism and thus affect leaf development. Blue light directly through the interaction with proton pumps and indirectly through receptors, affects proton pumps by modulating passive ion conduction of potassium and calcium channels. Conclusion According to the results of this research, it was found that exposing the plant to different light quality had different responses in the cucumber plants. Although variables such as dry weight and the amount of photosynthetic pigments were not significantly affected by light quality, however, traits such as plant height, leaf area, root dry weight, and plant fresh weight were affected by light quality. The affected parameters are among the traits that are influenced by the gibberellin hormone and according to the reports related to the effect of light quality on the gibberellin biosynthesis and response to this hormone. It seems that plant action to the quality of light can be attributed to the regulation of this hormone. So it is possible to choose the appropriate light quality in fully controlled conditions according to the production goal and results. In this research, according to the plant leaf rea, root dry weight and plant height, it was determined that white light can be used in the seedling production stage.
Breeding and Biotechnology of Plant and Flower
Ahmad Sharifi; Maryam Moradiyan; Nasim Safari; Azadeh Khadem; Seyyedeh Mahdiyeh Kharrazi
Abstract
Introduction: Ornamental foliage plants are commonly used for beautifying indoor spaces. Consequently, determining the best method of mass propagation in a short time, is necessary for these plants. For this purpose, an experiment was designed and performed to micropropagate the Singonium ornamental ...
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Introduction: Ornamental foliage plants are commonly used for beautifying indoor spaces. Consequently, determining the best method of mass propagation in a short time, is necessary for these plants. For this purpose, an experiment was designed and performed to micropropagate the Singonium ornamental plant.Materials and Methods: For the first stage, the effect of different plant growth plant growth regulators on the regeneration of nodule explants was evaluated. In this experiment, 1 cm nodal explants were placed in semi-solid MS culture medium containing different concentrations of BA and Kin (0, 1, 2, 3 and 4 mg/l) in combination with 0.2 mg/l IAA. This experiment was performed as a factorial based on a completely randomized design with four replications. The first factor included different types of cytokinin (BA and Kin) and the second factor included different concentrations (0, 1, 2, 3 and 4 mg/l). In the second stage, the effect of different types of culture medium and its different concentrations on plantlet proliferation was investigated. This study was performed as a factorial experiment based on a completely randomized design with five replications. The first factor included the type of culture medium (MS and B5) and the second factor was the different concentrations of culture medium (0.5 and 1). In the third stage of the experiment, the acclimation of in vitro plantlet was investigated. This experiment was performed as a completely randomized design with three replications. The experimental treatments included different culture media: vermiculite, peat moss, vermiculite + peat moss, perlite + peat moss, perlite, coco peat + vermiculite, coco peat + perlite, coco peat and rock wool.Results and Discussion: According to the results of the first experiment, it was found that the use of cytokinin in MS culture medium is effective on plant regeneration. The highest number of regenerated plantlet was observed in culture medium containing 4 mg/l BA with 0.2 mg/l IAA. It is noteworthy that with increasing BA concentration in the culture medium, the plant height decreased, but in contrast, the number of produced plantlets increased. Benzyl aminopurine (BAP) has been introduced as the most important and effective cytokinin in inducing and increasing branching in plants. Research has shown that the use of external benzyl adenine affects plant growth by affecting plant cells or by controlling the accumulation of a number of cytokinin compounds. As a result, the use of cytokinins in culture medium under in vitro culture conditions is necessary to induce and increase cell division. According to the second experimental results, produced plantlets in MS culture medium had higher height, number of roots and root length compared to B5 culture medium. Results also demonstrated that the use of ½ MS in the propagation stage of this plant is appropriate due to the improvement of growth traits such as plantlet height and root length. The use of optimal and suitable culture medium is very effective in the success of plant micropropagation. In the present study, the use of MS culture medium showed better performance compared to B5 culture medium. The appropriate amount of components, better ion strength and more minerals in this culture medium compared to B5 culture medium are probably the factors influencing its superiority in in vitro culture. In the acclimation stage, the use of vermiculite + peat moss culture medium led to 100% adaptation of plants and improvement of growth traits in the plant.Conclusion: The results showed that the type and concentration of cytokinin had a significant effect on the most of the evaluated parameters. With increasing the concentration of cytokinin in the culture medium, the number of regenerated plantlet was increased, but on the other hand, the height of regenerated plantlet also decreased. The use of culture medium containing BA compared to KIN had a more pronounced effect on increasing the number of regenerated plantlets. Application of MS medium compared to B5 medium was more effective in increasing plantlet height, root length, number of roots and number of produced plantlets. Also, half-strength MS medium, increased plantlet height and root length. Therefore, at this stage of propagation, the application of ½ MS culture medium is recommended. In the acclimation stage, it can be stated that the use of vermiculite substrate in combination with peat moss is a suitable option considering 100% compatibility of syngonium plantlets and improvement of growth traits in comparison with other substrates.
Rasul AbaszadehFaruji; Mahmood Shoor; Ali Tehranifar; Bahram Abedy; Nasim Safari
Abstract
Introduction: Ornamental plants play a vital role in meeting the mental and spiritual needs of peoplethat considered significance from commercial point of view as well. Optimal production of agricultural products requires suitable soil and adequate and absorbable nutrients for plant. Organic materials ...
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Introduction: Ornamental plants play a vital role in meeting the mental and spiritual needs of peoplethat considered significance from commercial point of view as well. Optimal production of agricultural products requires suitable soil and adequate and absorbable nutrients for plant. Organic materials are important because ofimproving soil physical properties and soil fertility. Soil fertility depends on the content oforganic matter as well as the quality, quantity and dynamics of these materials insoil. Organic acids are an important source of organic matter. One of the most abundant forms of organic matter in nature is humic compounds which can be found in all soil and water environment. They play an important role in cation exchange, nutrients release, phosphorus buffering capacity and metal and toxic organic molecules maintenance.
Materials and Methods: In order to evaluate the effect of humic substances on morphological characteristics of geranium, thisexperiment was conducted in research greenhouse of Ferdowsi University of Mashhad during the years 2014 and 2015. The experiment was carried out as factorial based on completely randomized design with two factors and three replications. The first factor hadfour levels of humic acid (0, 0.2, 0.5 and 1 g/l), and the second hadfour levels of fulvic acid (0, 0.2, 0.5 and 1 g/ml). Treatment was usedalong with irrigation. Morphological characteristics included the number of leaves, number of nodes, number of branches, plant height, root length, leaf area, fresh weight of shoot, fresh weight of leaf, fresh weight of root, dry weight of shoot, dry weight of leaf, dry weight of root, volume of shoots, volume of root, fresh weight of shoot were measured at the end of the experiment. Statistical analysis of the results was performed by using Jmp-8 software. Charts were drawn using Excel 2010 and difference among treatments means were compared with LSD test.
Results and Discussion: The results of means comparison showed that combined use of humic acid and fulvic acid hadpositive effects on growth traits such as height, internode length, root length, fresh weight of shoot, fresh weight of root, fresh weight of leaf, dry weight of shoot, dry weight of leaf, volume of shoot, volume of root and leaf area. Research had shown that the application of humic fertilizers increased nitrogen content in shoots of the plant. It wasreported that nitrogen compounds existed in humic acid are important factors affecting the growth of plants. Humic acid also increasedshoot growth by increasing the uptake of nitrogen, calcium, phosphorus, potassium, manganese, zinc, iron and copper as well as hormone-like properties. It wasalso found that humic acid enhancedplant growth by increasing the activity of the RuBisCO enzyme and the subsequent increase in photosynthetic activity. Furthermore, humic acid reduced the pH of alkaline soils and causedthe nitrogen to be absorbed to a greater extent. The use of humic substances increased the leaf area and thus photosynthesis, therefore leading to the production of more dry matter in plants. Humic fertilizers also had a significant effect on root growth. Researchers had suggested that the presence of oxygen groups in humic acid increased lateral root growth. Although humic acid increased the growth of both root and shoot, its effectiveness on the root system wasmore evident.
Conclusions: This experiment was conducted with the aims of evaluating the effect of humic organic fertilizers, reducing the harmful effects of chemical fertilizers and improving the quality of plant growth in geranium. According to the results obtained from the present research, it can be concluded that combined application of humic acid and fulvic acid had greater effects on the majority of traits compared to the sole application of aforementioned compounds.
