Ornamental plants
Mohadeseh Piri; Zohreh Jabbarzadeh
Abstract
Introduction Lisianthus (Eustoma grandiflorum) from Gentianaceae family is from wild flowers of north and west America. Lisianthus, a relatively new floral crop to the international market, quickly ranked in the top ten cut flowers worldwide due to its rose-like and blue flowers. It is also widely ...
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Introduction Lisianthus (Eustoma grandiflorum) from Gentianaceae family is from wild flowers of north and west America. Lisianthus, a relatively new floral crop to the international market, quickly ranked in the top ten cut flowers worldwide due to its rose-like and blue flowers. It is also widely used as a flowering potted and bedding plant. Lisianthus ‘Mariachi Blue’ is cultivated as a cut flower. Salicylates have very beneficial effects on plant growth and development. The effect of phenolic compounds in many biochemical and physiological processes including photosynthesis, ion adsorption, membrane permeability, enzyme activity, flowering, stimulation of plant resistance systems, heat production and plant development has been proven. The most famous member of this group is salicylic acid, which as a simple phenolic compound, is naturally produced by plants. Salicylic acid (SA) is considered to be plant signal molecule that plays a key role in plant growth, development, and defense responses. Polyamines (PAs) are ubiquitous and biogenic amines that have been implicated in cellular functions in living organisms. In plants they have been implicated in a wide range of biological processes including cell division, cell elongation, senescence, embryogenesis, root formation, floral initiation and development, fruit development and ripening, pollen tube growth and plant responses to biotic and abiotic stress. Sodium nitroprusside is a nitric oxide releasing agent. Nitric oxide is a gaseous free radical that can disperse very rapidly through cell membranes due to its gaseous nature and medium shelf life, without a carrier. Nitric oxide (NO) is an unstable environmentally-friendly gas radical that is used to protect the postharvest longevity of different horticultural crops. In addition to controlling harvested crop senescence, NO is involved in many plant processes, e.g., germination, growth and development, photosynthesis, pigment synthesis, defensive system, and many others. In the present study, we investigated the effects of foliar application of salicylic acid, spermidine and sodium nitroprusside on some morpho-physiological characteristics and vase life of lisianthus flowers ‘Mariachi Blue’.Materials and Methods This study was conducted based on a completely randomized design with 10 treatments, 4 replications which each replication containing 2 pots. The treatments were included spermidine at concentrations of 0.5, 1 and 2 mM, salicylic acid at concentrations of 0.5, 1 and 1.5 mM, sodium nitroprusside at concentrations of 50, 100 and 200 μM and control (without any application of growth regulators) as foliar application at intervals of 15 days for 2 months. Plant characteristics including leaf area, stem length, fresh and dry weight of leaves and flower, number of buds, flowers’ length and diameter, photosynthetic pigments and vase life were assayed. To perform analysis of variance and compare the mean of the studied traits, SAS software version 9.1 was used. The means were compared using the Tukey multi-domain method at a probability level of 1%. Also, Excel (2016) software was used to draw the chart. Results and Discussion The results obtained from analysis of variance in this study showed that the effect of growth regulators used in the study was significant at the level of 1% probability on all morphological traits measured, photosynthetic pigments and vase life of lisianthus flowers. Mean comparison graphs showed that salicylic acid, spermidine and sodium nitroprusside had a positive effect on some morphological traits, photosynthetic pigments and vase life compared to control. It can be concluded that, salicylic acid caused to increase all parameters except the flowers’ fresh weight compared to control. Spermidine increase stem length, leaf fresh weight, flowers’ fresh and dry weight, length, and diameter, chlorophyll index, chlorophyll b, and carotenoid and vase life of flowers. Also, sodium nitroprusside had beneficial effects on all parameters in this research except leaf area, leaf dry weight, chlorophyll a and vase life of flowers. Salicylic acid plays an important role in regulating some physiological processes of plants such as growth and development, ion uptake and transport, stomatal conductivity, and membrane permeability, which is effective in plant photosynthesis and with increasing photosynthesis, plant growth rate increases. Polyamines such as spermidine are involved in a wide range of developmental stages including cell division, embryogenesis, root growth, and flowering. Sodium nitroprusside is involved in the most important plant processes such as photosynthesis, respiration, growth and cell division. Probably, these growth regulators, due to their effect on plant growth, flowering, as well as photosynthetic pigments, have caused the increment of plant biomass and vase life.Conclusion In the present study, the effect of salicylic acid, spermidine and sodium nitroprusside on some growth and flowering characteristics, photosynthetic pigment and vase life of Eustoma grandiflorum ‘Mariachi Blue’ was assayed. According to the results of the present study, it can be concluded that these growth regulators improved growth indices, flowering parameters, photosynthetic pigment and vase life of flowers. According to the results, the appropriate concentrations for salicylic acid were 1 mM, for spermidine, 1 mM and for sodium nitroprusside were also 50 and 100 μM.
Maryam Haghighi; Bahareh Naghavi
Abstract
Introduction: Salinity has deleterious effect through ion toxicity and changes nutrient balance on plant growth parameter. For decreasing the hazardous effect of salinity stress, some effort has done to reduce uptake and accumulation of Na. Adding of Ca decreased these deleterious effect of salinity. ...
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Introduction: Salinity has deleterious effect through ion toxicity and changes nutrient balance on plant growth parameter. For decreasing the hazardous effect of salinity stress, some effort has done to reduce uptake and accumulation of Na. Adding of Ca decreased these deleterious effect of salinity. Calcium ions have significant effects on the physiological processes of plants and improve the morphological and biochemical factors of plants under salinity stress. The effect of calcium on reducing the harmful impacts of salinity from sodium depends on the plant type, calcium concentration and sodium source. Recently, the addition of nanoparticles to plants as fertilizers has attracted the attention of researchers because of its unpredictable effects, such as faster and easier penetration into the membrane of the cell. A few studies have examined the effect of different nanoparticles on the growth and physiology of plants. So, a research was conducted to investigate the effects of salinity and supplemental calcium in the form of spraying into two metal and nano-metal forms on vegetative growth of tomato plants under crop cultivation conditions.
Materials and Methods: To study the effect of CaCl2 and Nano-Ca on tomato (Lycopersicon escuhentum var. Falcato), a factorial experiment based on completely randomized design (CRD) with 4 replicates was designed with NaCl (0, 25 and 50 mM) and Ca and N-Ca (0, 150 and 200 mg/l) in Isfahan University of Technology greenhouse. Indicators include chlorophyll index, relative water content, ion leakage, leaf water potential, root and shoot dry weights, root and shoot length and root volume were measured. Finally, the analysis of the results was done by statistical statistic software and comparing the meanings by LSD test at 5% level.
Result and Discussion: Results showed that Ca and Nano-Ca was effective on decreasing hazardous effect of salinity on fresh and dry weight of shoot and root volume and Ca was more effective than Nano-Ca. In high salinity level (50mM NaCl), application of 150 mg/l Ca increased fresh and dry weight of root, fresh weigh of shoot and root volume by 60, 63, 50 and 70 % compare to control ,respectively. As well as, the highest root length and shoot was observed in this treatment. Application of 200 mg/l calcium and 150 mg/l of nano-calcium significantly improved chlorophyll content in 50 mM sodium chloride treatment. The plant's compatibility mechanism is very complex in the salinity conditions, from reasons for the growth of the plant under saline conditions are the accumulation of toxic ions, chlorine and sodium in plant tissues, which reduces enzyme activity and changes the pattern of carbohydrate distribution. Loss of the fresh and dry weight shoots and root of tomato has been reported in salinity conditions, which can be attributed to reduce plant growth due to the decrease in leaf area growth and thus the reduction of photosynthesis and the production of proteins. There is little research on the use of nanoparticles in plant growth and the use of nano-calcium has been used to reduce salinity stress for the first time, but the beneficial effects of some nano-materials on plants have been proven. With the use of titanium and nano-titanium in spinach, nano-titanium increases the fresh and dry weight of the plant relative to the use of titanium. In this study, the effects of calcium salinity stress were observed, but nano-calcium had less effects than calcium, and probably due to the fact that the concentrations of nano-calcium were used, using less concentrations in future research to achieve possible concentrations are suggested.
Conclusions: The use of nano-calcium to reduce salt stress was used for the first time in this experiment. The results of this experiment showed that the application of 150 mg calcium per liter on many tomato traits such as root and shoot fresh weight, root length shoots and root volume were effective under salinity stress, especially intense salinity (50 mM sodium chloride). The comparison of the effects of calcium and nano-calcium showed that the particle size reduction hadn’t shown a significant effect on calcium salt modification and may be due to the concentrations of nano-calcium. Therefore, nanotechnology needs more research in the application of nano-calcium and other nano-materials. Ca also alleviated the hazardous effects of salinity but comparing Ca and nano-Ca showed that nano-Ca has not significant alleviating effect on salinity stress.
Golnar GhazianTafrishi; Hossein Arouiee; Majid Azizi; Hamidreza Khazaie; Saeid Reza Vessal
Abstract
Introduction: Plants native to tropical and subtropical climates which grown in the temperate climate zone, suffer chilling injury when exposed to non-freezing temperatures for a certain period of time. The optimum growth temperature for cucumber (a tropical plant) is 20 to 25°C. Cucumber is sensitive ...
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Introduction: Plants native to tropical and subtropical climates which grown in the temperate climate zone, suffer chilling injury when exposed to non-freezing temperatures for a certain period of time. The optimum growth temperature for cucumber (a tropical plant) is 20 to 25°C. Cucumber is sensitive to temperatures lower than 10 °C. Cucumber area of production exposes to late spring and early autumn cold weather in Khorasan-e-Razavai, Iran. Studies showed that chilling leads to an alteration in fatty acid composition of membrane lipids and its permeability, changes in photosynthetic pigments content and decrease in photosynthesis. Many researchers pointed to a possible role of polyamine compounds in plant defense against environmental stresses. Exog enous application Spd could prevent the electrolyte and amino acid leakage or recovering the plasma membrane damage in rice and cucumber in response to salinity, chilling and water stressed conditions.
Materials and methods: A factorial experiment, based on completely randomized design was conducted to investigate the effect of short-term chilling on cucumber plantlets which was earlier treated with spermidine. Factors were included two levels of temperature (6 and 12°C) and four levels of spermidine (0, 0.25, 0.5 and .0.75 mg/L). The studied cultivar was ‘Super-Dominus’. In order to determine the extent of chilling injury, plants of each treatment were rated based on visual symptoms. By assigning values of 1, 2, 3, 4, and 5 while 1: no visible symptoms 2:5% of leaf area necrotic, 3: 5-25% of leaf area necrotic, 4: 26-50% of leaf area necrotic but plant still alive, 5: lost, entire plant necrotic and collapsed. Measured traits were root and shoot length, root and shoot dry weight, root and leaf electrical leakage, and leaf chlorophyll content.
Results and discussion: Plants which exposed to low temperature showed chilling injury symptoms (5-25% leaf area necrotic). The symptoms reduced (less than 5% leaf area necrotic) by using 0.25 and 0.5 mg/L spermidine. The symptoms enhanced by 50% by applying 0.75 mg/L spermidine at 6°C. Analysis of variance showed that there was significant difference between temperature levels, spermidine levels and interaction between them in respect to root length, shoot length, shoot dry weight and root and leaf electrical leakage. Root dry weight, root to shoot ratio and chlorophyll content just affected by temperature and spermidines levels but not by interaction between them. Root and shoot length and dry weight decreased by low temperature. At cold stress condition growth decreased due to a reduction in photosynthesis and carbohydrate metabolism .Root and shoot length decreased more than 79% at 6°C compare with 12°. Root to shoot ratio increased at cold condition which was the result of lower root weight loss in response to cold temperature compared with shoot weight losses. Electrical leakage (EL) enhanced in leaf and root cells at chilling temperature, but the enhancement was significantly more at root cells. Electrical leakage enhanced more than 52% in root cells at 6°C compared with 35% in leaf cells. EL suppressed, using 0.25 and 0.5 mg/L spermidine while an increase observed in El at 0.75 mg/L spermidine. The lowest EL percentage observed for leaf samples treated with 0.25 and 0.5 mg/L spermidine at 12°C. The highest EL percentage belonged to root samples treated with 0.75 mg/L Spd at 6°C .Chlorophyll content (ChlC) decreased at cold condition. ChlC was 52% at12°C compared with 37% at 6°C. High significant correlation observed between chlorophyll content and shoot dry matter (r2= 0.96**). Root and shoot length and dry weight and leaf chlorophyll content enhanced using 0.25 and 0.5 mg/L spermidine at both chilling and control temperatures. A decrease observed in measured traits applying 0.75mg/L spermidine. There was no significant difference between 0.25 and 0.5 mg/L spermidine levels in respect of measured traits expect for shoot dry weight. Spermidine enhances chilling tolerance in cucumber by prohibiting the activity of NADPH oxidase. The capacity of PAs to enhance the tolerance of cucumber to chilling injury is attributed to the scavenging of H2O2 production under chilling condition.
Conclusion: Results showed that root and shoot length and weight, root and leaf electrical leakage and chlorophyll content of leaf adversely affected by chilling stress. Using 0.25 mg/L spermidine modulates plant responses to chilling stress. There was no significant difference between 0.25 and 0.5 mg/L spermidine in respect of measured traits. But all measured traits adversely affected using 0.75 mg/L spermidine at both 6 and 12°C.
Mohammad Golrang; Mahmood Shoor; Ali Tehranifar; Seyed Mmohammad Javad Mousavi
Abstract
Since lawn cultivation is a laborious process, we need new and quick methods of cultivation such as sod production to revive and repair green spaces. Mean while, the kind of cultures media and the types of cultures net which are used tostreng then the lawn parts (sodding) may infiuence the quality pf ...
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Since lawn cultivation is a laborious process, we need new and quick methods of cultivation such as sod production to revive and repair green spaces. Mean while, the kind of cultures media and the types of cultures net which are used tostreng then the lawn parts (sodding) may infiuence the quality pf the produced sod. This study investigated the effect of four kinds of soil combinations including: clay, (30% compost + 70% clay), (30% clay + 40% sand + 30% compost) and (10% pitmass + 90% clay). Also, it aimd to study four types of network such as: plastic guid, metallic guid, plastic bag and guidless. This investigation was dcne without any control network in production. In addition, factorial analysis was used based on 16 random treatments in three replicates within two years (2009,2010). The lawn seed under investigation was in the form of the one used in sports, fields and it was a mixture of three species and five cultivar. The results displayed that the mean of color charactristics, chlorophyll a, total chlorophyll, level of chlorophyll after first winter frost and growth rate were significantly more in the bed cultuer ( 30% compost + 70% clay) than the last of bed cultuer. On the other hand bed cultuer containing hight percentage of clay displayed more uniformity and density of weed. Regarding color, chlorophyll b and level of chlorophyll after first winter frost, the bed cultuer with hight compost were better than the others in the growth rate. The highest rigidity obtained in plastic bag net and the level of weed in this treatment is compairing with others were lower in significant.
