Ornamental plants
Mojdeh Osku; Azizollah Khandan Mirkohi; Roohangiz Naderi
Abstract
Introduction The genus Chlorophytum (also known as spider plant) which is mainly cultivated as an ornamental plant for its slash and colored leaves, specifically distributed in the pantropic regions. It is a perennial rhizomatous plant with often short and indistinct rhizomes, while with thicker ...
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Introduction The genus Chlorophytum (also known as spider plant) which is mainly cultivated as an ornamental plant for its slash and colored leaves, specifically distributed in the pantropic regions. It is a perennial rhizomatous plant with often short and indistinct rhizomes, while with thicker or slightly fleshy roots. The roots of these species are considered as one of the important phytochemical components. the use of Chlorophytum comosum as a contaminant accumulator has already been documented in the literature.This plant is a soil conditioner and can absorb lead, cadmium, Se and As while its leaves accumulate mercury. It is also able to absorb toxic organic pollutants such as formaldehyde and benzene and is also able to retain CO2. Leaf surface morphology has been shown to affect the ability of a particular plant to retain contaminants. Chlorophytum comosum introduced as a plant that requires high nitrogen. Nitrogen is an essential macro element for the growth and development of plants which involved in many physiological reactions and it is one of the elements that plants need in all their activities. The effect of N form on plant growth depends on plant species and nitrogen level of the soil. Plants absorb both ammonium (NH4+) and nitrate (NO3-) from soil solution, and these two mineral forms are their most important sources of nitrogen to supply the plant demand. Absorption of ammonium by plants requires less energy than absorption of nitrate. It seems that most plants have the best performance in a certain ratio of nitrate to ammonium (NO3-/NH4+ ratio). This ratio seems to regulate the distribution of absorbed nitrogen between the branches and roots. It may also vary between species. The optimal ratio may also depend on the environmental conditions such as pH, light intensity, and root zone temperature. This study was performed to determine the effect of different levels of ammonium nitrate on growth, yield factors and ornamental aspects of the spider plant as a desired ornamental product. The use of ammonium nitrate to meet the houseplants demand considering the supply of both types of nitrogen sources, increases the yield and quality of these plant. However, despite the importance of the nitrogen in the performance of this ornamental plant (Chlorophytum comosum), the desired amount of nitrogen for its growth and quality has not yet been reported. Therefore, the present study was conducted to investigate the effect of different levels of ammonium nitrate on the growth and physiological characteristics of spider plant to find the best level of application of ammonium nitrate fertilizer as an easily available source to increase the growth and visual quality of this plant.Materials and Methods This research was conducted based on randomized complete block design (RCBD) with four treatments and three replications. Treatments include four levels of ammonium nitrate of 100 (control), 200, 400, 600 mg-1 kg of soil. Treatments applied first at the substrate preparation process and then was applied in the one third depth of each pot, monthly. Desired factors such as morphological characteristics (plant height, leaf number, stolon number, fresh weight, dry weight, root fresh weight, root dry weight, root volume, root depth, root length, pot weight, leaf area) and physiological characteristics (total chlorophyll, total protein, texture nitrate and proline) were evaluated. Also soil analysis was performed before starting of the experiment. Statistical analyses of the data for examined traits were performed using SAS software and comparisons of means using Duncan's multiple range test, at 5% probability level.Result and Discussion The results indicated that the application of ammonium nitrate fertilizer significantly improved most of the studied traits. Supplying ammonium nitrate fertilizer at desired level meet the nitrogen demand of Spider plant during the growth and improved production of biomass. The plant height, leaf number, fresh weight, dry weight, root fresh weight, root dry weight, and leaf area were increased by increasing ammonium nitrate level. Nitrogen fertilizers play an important role for increasing plant yield by expanding shoots and producing sufficient carbohydrates. In addition to plant growth, they also affect plant morphology. Maximum amount of protein, nitrate of tissue and total chlorophyll observed in 400 mg-1kg of ammonium nitrate level. Nitrogen is one of the essential elements that plays an important role in the production of chlorophyll and protein, therefore the use of nitrogen fertilizers leads to synthesis of chlorophyll and protein at higher level. The highest amount of proline (11.20 μg-1 mL) was measured at 600 mg-1kg of ammonium nitrate level and the lowest (3.57 μg-1 mL) in the control, because with high consumption of nitrate, the plant needs more water and nitrogen is a structural component of proline. Accumulation of proline helps the plant to survive and recover after drought stress.Conclusion According to the results of our experiment, application of nitrogen fertilizer had a positive effect on growth, and consequently led to increase the plant vegetative yield. Treatment of 400 mg-1kg of ammonium nitrate level increased growth and yield factors and the ornamental aspect of Spider plant as a desired ornamental crop. Application of 400 mg-1kg of ammonium nitrate level are recommended to access an acceptable quantitative and qualitative yield in this plant.
Azizollah Khandan Mirkohi; Seyyedeh Razieh Waeez Mousavi; Ahmad Khalighi; Rouhangiz Naderi
Abstract
Introduction: Cultivation of ornamental plants in terrariums is common, but the use of flowering plants in such environment is difficult and rarely seen. Common geranium (Pelargonium hortorum L.H.) is the most well-known potted and garden plant in the top of 25 popular world's market rankings. Today, ...
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Introduction: Cultivation of ornamental plants in terrariums is common, but the use of flowering plants in such environment is difficult and rarely seen. Common geranium (Pelargonium hortorum L.H.) is the most well-known potted and garden plant in the top of 25 popular world's market rankings. Today, one of the main goals of commercial producers is the production of the uniform plants in terms of morphological traits such as uniformity in the height that needs some management. To achieve this objective plant genetic potential, managing the growth and environmental factors, restrictions on root environment, water and nutrition to a level that does not affect the quality as well as application of chemical plant growth retardants (PGRs) could be considered. Paclobutrazol (PBZ) commercially known as Bonzi and chlromequat chloride (CCC) known as cycocel are commonly used to control the height of some pot plants. Additionally, Benzyladenine (BA) as a synthetic cytokinin can influence the growth characters of plants. This experiment conducted to evaluate the effect of paclobutrazol, cycocel and benzyladenine on the growth and flowering of geranium as a flowering terrarium plant.
Materials and Methods: The effect of PBZ, CCC and BA evaluated as a factorial experiment based on CRD on the growth and flowering of geranium (Pelargonium hortorum L.H. Bailey ‘Horizon’) as terrarium plant. At first, geranium seeds planted in tray cells as plugs filled by sieved black peat to below 2 mm in early autumn, Oct. 2015. Seedlings were grown in a greenhouse conditions with an average day/night temperatures of 25/20 ± 2 °C, nourished with 1:2 ratio diluted Hoagland nutrient solution as irrigation demand, until 2-4 leaves stage then transferred into terrarium containers (with 20 cm of middle diameter and 15 cm of height). Inside container relative air humidity was about 75±5% and growing environment light intensity (PPF) was about 500 µmole m-2S-1. Irrigation and nutrition also applied at seedling stage in terrarium. Terrarium glass container totally filled to a quarter of volume considering a drainage layer of gravel, activated charcoal, a layer of substrate barrier (plastic net), potting soil containing of 20 vol.% sieved field loam soil, 10 vol.% of fine perlite and 70 vol.% of sieved black peat. PBZ at the levels of 0, 25 and 50 ppm and CCC at the levels of 0, 1000 and 2000 ppm applied one month after transplanting (Feb. 2015) and BA treatment for flowering management applied at the levels of 0, 50 and 100 ppm four months after transplanting (May 2016). Growth and flowering characters evaluated thoroughly while root and shoot fresh and dry weight, photosynthetic pigments of chlorophyll, carotenoids, and anthocyanin index assessed at the end of the experiment.
Results and Discussion: Both growth retardants PBZ and CCC led to a significant reduction in plant height in high concentrations. Thus, the effect of PGRs on plant height was significant, while the effect of BA and its interactions by PGRs on this trait was not considerable. Effective treatments on this trait were PBZ in concentration of 50 ppm and then CCC in 2000 ppm. In particular, the use of these concentrations without BA treatment led to the shortest plants. Comparison of plants cultivated in the pot and terrarium conditions showed that the growth conditions had a considerable and significant impact on plant height and growth. Stem diameter, number of leaves and leaf area significantly reduced by PBZ compared to the control, but CCC did not show a significant effect on these traits. Smaller stem diameter occurred through 25 ppm of PBZ together with 50 ppm of BA. Application of PBZ especially at 25 ppm resulted in a significantly reduced number of plant leaves and leaf area compared to the control and application of CCC. Application of CCC at the level of 2000 ppm combined with BA of 50 ppm caused to a significant increase of leaf area compared to the control. Results on the number of lateral branches showed that application of PGRs had no effect on this character, while restriction of growth in terrarium conditions led to decrease in the number of lateral branches. Number of lateral branches raised by application of BA and CCC, while less number of branches observed with PBZ treatments especially at the level of 25 ppm. Chlorophyll and anthocyanin content of leaves decreased by both retardants. Days to flowering shortened by PBZ treatment of 50 ppm and slightly by CCC treatment of 1000 ppm in terrarium conditions. In general, flowering process accelerated via these treatments, while PBZ of 25 ppm and CCC of 2000 ppm delayed the flowering of plants compared to the control. The acceleration effect of 50 ppm PBZ was superior to the effect of 1000 ppm of CCC. The effect of BA on flowering time was insignificant despite of initial prospect. Finally, the photosynthetic pigments, leaf area and stem diameter increased because of BA, while flowering characters not influenced by means of BA. In general, 50 ppm of PBZ and without BA treatment was able to improve production characters of geranium plants in terrarium conditions.
Conclusions: The goal of this research was managing the growth and flowering of geranium in the restricted terrarium conditions by PGRs. It was found that treatment of plants by 50 ppm of PBZ could properly control the plant height and whereas positively accelerated flowering without and negative side effects on the plant performance. It seems that a good hormonal balance performed by this concentration of PBZ compared to CCC and BA. Early flowering is a positive quality trait for the most flowering ornamental plants. However, BA application itself and in interaction with CCC could enhance the photosynthetic pigment contents and thus improved the growth characters but it could not influence flowering traits even though delayed the flowering, significantly. Restriction of the root area via planting in terrarium could considerably limit the vegetative growth characters and delayed the flowering compared to the potted plants.
Azizollah khandan Mirkohi; Nakisa Baie; Ebrahim Hadavi
Abstract
Introduction: Regular watering and application of nitrogenous fertilizers in turf-grasses is a conventional operation, especially in warm and dry or semi-dry climates, which arecommon in many parts of Iran. Nitrogen is a mobile nutrient in soil or substrates, especially in the form of nitrate. Nitrate ...
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Introduction: Regular watering and application of nitrogenous fertilizers in turf-grasses is a conventional operation, especially in warm and dry or semi-dry climates, which arecommon in many parts of Iran. Nitrogen is a mobile nutrient in soil or substrates, especially in the form of nitrate. Nitrate leaching due to the regular watering has been reported in many sources. The managing nitrogen application can help to minimize the loss of this element regarding the ability of soil-plant system. Attempts have been made to control the growth of turf-grass using various types of chemicals, but similar to the concerns associated with the consumption of nitrogenous fertilizers, this is also concerned with environmental pollutions. Therefore, the growth of turf grasses can be controlled without using chemicals and by limiting the use of nitrogen and managing the irrigation.The purposes of this study were to limit the application of nitrogen in order to control vegetative growth of the turf grass and maintain its visual quality, and to manage irrigation in order to preserve this mobile element (nitrogen) near the root system and prevent its leaching.
Materials and Methods:The effects of reduced water and nitrogen supply on the control of vegetative growth of turf grasses, commonly named as sport turf,were evaluated.Therefore, an experiment was designed in a factorial based on randomized complete block design with three replications. Mixed seeds of sport turf grass were planted with the density of 40 g m-2in boxes, which placed atthe depth of30 cm and leveled with sandy loam soil in mid-spring. Nitrogen was applied as ammonium nitrate via fertigation in five levels of 0, 0.5, 1, 1.5 and 2 mg m-2 month-1, andirrigation treatments performed at four levels of 100%, 80%, 60 % and 40% of field capacity. Watering was done every two days for 5 months during the warm season of the year after the first mowing on June 2013. Some traits such as plant height, fresh and dry weight, density, color and quality, and chlorophyll and proline contents were evaluated during growth period or at the end of the experiment.The data were subjected toananalysis of variance (SAS, 1996),and differences among the treatments were compared using Duncan’s multiple range test at 95% probability level.
Results and Discussion: The results showed that decreasein nitrogen level up to 0.5 gdid not significantly change density index,,whilethe index showed a significant reduction in treatment containing zero nitrogen application and the lowest irrigation regime (40% of the field capacity).Quality and color of the turf grass had no significant correlation with nitrogen treatment, while the factor was significantly decreased when irrigation regime of 40% of the field capacity was applied. It was determined that although color of the turf grass was greener with lower levels of water,a good color was found with high level of non-organic fertilizer at the time that the amount of nitrogen leaching was also limited. Therefore, regardless of the different nitrogen levels applied, quality and color indiceswerethe lowest when irrigation at 40% of field capacity was applied. Limiting the level of nitrogen up to 0.5 gramand irrigation up to 60% of field capacity was desirable to control and reduce the height of turf grass. Reduction in water level up to 80% of field capacity caused no significant changes in fresh weight, but a significant decreasewas resulted with the reduction of water consumption up to 60% of field capacity. The maximum fresh weight was found with 1.5 grams nitrogen. However, reducing nitrogen level upto 0.5 gramdid not bring about significant changes in this trait. Dry weight also followed the same pattern as fresh weight. Although reduction in the level of applied nitrogen did not reduce the height, it caused a significant reduction in fresh and dry weight of the turf grass. The highest chlorophyll content was found when 2 grams of nitrogen and irrigation regime of 40% of field capacity were used. Regardless of the nitrogen level, the highest chlorophyll content was found in irrigation of 40% of field capacity,while the lowest amount was observed in the treatment containing irrigation at100 and 80% of field capacity. Plants were dark green in 40% of field capacity. Proline content showedincreasealong with the decrease inirrigation as well as nitrogen levels.
Conclusion:Plant height, fresh and dry weight, chlorophyll and proline contents were significantly affected by limiting the use of nitrogen and water, but density and quality indices were not significantly influenced. Regardless of the nitrogen levels applied, quality and color traits were the lowest only in irrigation regime of 40% of field capacity. Therefore, it was concluded that reduction of nitrogen supply to 1 mg m-2 month-1and irrigation regime up to 60% of field capacity could result in thereduction ofvegetative growth of turf grass, while quality traits were not affected negatively.
