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.
Seyyed Najmodin Mortazavi; Fatemeh Khodabandelu; Mohammad Hossein Azimi
Abstract
Introduction: Brassica Oleracea L. is biennial of cabbages family. This plant is valuable for its leaves and resistivity against cold weather. Cabbages are resistant to cold and suitable for landscape in cold areas. In some ornamental plants, the control of plant size, vegetative growth and size reduction ...
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Introduction: Brassica Oleracea L. is biennial of cabbages family. This plant is valuable for its leaves and resistivity against cold weather. Cabbages are resistant to cold and suitable for landscape in cold areas. In some ornamental plants, the control of plant size, vegetative growth and size reduction is necessary to enhance sale. Salicylic acid is a phenolic compound that is produced naturally in plants and on multiple factors affect. Cycocel is one of the retarder material to the growth. This research was performed in order to best retarder concentration of growth factors to improve the quantity and quality of ornamental cabbage landscape.
Materials and Methods: This study was done as factorial experiment in a randomized complete block design with three replications. Experiment was performed with two factors of cycocel with four levels (0, 50, 100, 150 mg.lit-1) and salicylic acid with four levels ( 0, 50, 100, 200 mg.lit-1) by spraying and every of them with three replications. In this experiment, traits such as plant height, antocianin, resistivity against cold weather, electrolyte leakage, rational component of water, chlorophyll, wet and dry weight of leaves, wet and dry weight of roots and the number of leaves were investigated. 80 numbers of uniform seedlings of ornamental cauliflower varieties of purple were prepared and after the reached the stage of 5 and 4 leaves to the pot of 10 to 15 cm and then after a short growing period for the the main land (bed) in loam soil with distance of 30 cm they were transferred. The treatment of salicylic acid and CCC two times and as foliar application on the leaves of cabbage was performed them with an interval 24 to 48 hours. The first stage of treatment on 18 and 19 November and after a few days of planting cabbage and establish them in the land, was performed. Statistical analysis using software MSTATC and comparing the average results using Duncan's multiple range test was performed.
Results and Discussion: Result from variance analysis showed that using of cycocel and salisilic acid have effect on growing, antocianin, number of leaves, rational component of water, chlorophyll, net weight of wet and dry leaves and roots, is significant in the level of one percent. The highest percentage of electrolyte leakage, leaf number, leaf and root dry weight and fresh weight were observed at 200 mg/ liter. The plant height, anthocyanin, cold resistance and Fresh weight of root were in control. High levels of chlorophyll and relative water content were observed in 100 mg/ liter. The use of Cycocel had a significant effect on growth traits. The highest dry weight of leaves, root dry weight and the highest percentage of electrolyte leakage in the treatment of 150 mg/ liter and the highest plant height, the highest percentage of relative water content and chlorophyll was observed in control. Most of the leaves, anthocyanin and cold resistance at the level of 50 mg/litter and highest fresh weight were observed at 100 mg/litter. The cycocel had no significant effect the growth traits.
Results showed that significant interactions SA and CCC one percent of levels on plant height, electrolyte leakage, number of leaves, anthocyanins, relative water content, chlorophyll content, leaf dry weight and root dry weight and the significant other traits has not. The results showed that spray application separately SA and CCC and the interaction of these compounds had significant effects on the plant height, anthocyanin extract, chlorophyll conten, fresh weight of root and dry weight of root. The results showed that the Cycocel and interaction of SA and CCC had a significant effect on the relative water content, but salicylic acid alone had no significant effect, which may be no significant in this experiment due to lack of relative water content in the presence of a low level of salicylic acid and or the duration of treatment was low. Cycocel alone and combination of SA and CCC had significant effects on dry weight of leaves, but salicylic acid alone had no significant effect.
Conclusions: Therefore, to increase the quantity and quality characteristics of ornamental cabbage treatments Salyslyk acid concentration of 200 mg l cycocel concentration of 150 mg per liter is recommended
