Growing vegetables
S. Parsajoo; F. Dashti
Abstract
Introduction
Plants are sometimes exposed to several stresses during their growth and development. Salinity stress is one of the most common abiotic stresses that significantly reduces the growth and yield of most plant species. A large part of the soils and a significant volume of all water resources ...
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Introduction
Plants are sometimes exposed to several stresses during their growth and development. Salinity stress is one of the most common abiotic stresses that significantly reduces the growth and yield of most plant species. A large part of the soils and a significant volume of all water resources in Iran are affected by salinity to varying degrees. Due to the rapid population growth and the need for more food and the water crisis, the use of unconventional water such as salt water or wells and treated wastewater in agriculture has received more attention. Soil and water salinity is one of the integrative problems in agriculture and is one of the most important barriers to crop production in the world. Salinity stress reduces the ratio of carbon dioxide to oxygen in the leaves by closing the leaves stomata and prevents the stabilization of carbon dioxide. Under these conditions, the formation rate of reactive oxygen species in chloroplasts and mitochondria increases, the electrons produced react with oxygen by photosynthesis and lead to the production of oxygen free radicals. These affects the growth, yield and quality of agricultural products. The use of antioxidant compounds can moderate the effects of this stress. Many compounds have been used to reduce the harmful effects of salinity stress. Ascorbic acid is a water soluble antioxidant and has some effects on plant resistance against environmental stresses by neutralizing free radicals. Researches showed that ascorbic acid increased plant resistance on various stresses such as salinity and drought. It has been widely used to control the effects of salinity stress. The aim of this study was to investigate the effect of ascorbic acid on resistance to salinity stress in bell pepper seedlings.
Materials and Methods
This study was done as a factorial experiment in a completely randomized design including ascorbic acid treatment (0, 1, 3 and 5 mM) and salinity stress of sodium chloride (0 and 100 mM) in 3 replications. The seeds of bell pepper Cv. California Wonder were planted in a seedling tray containing cocopeat. After emergence of cotyledons, they were fertilized with complete fertilizer (N20, P20, K20). At the stage of three true leaves the salinity treatment were started. One week before the beginning of salinity treatment, ascorbic acid was sprayed on plants and repeated two more times by seven days interval. Salinity treatment was applied by irigation for three weeks. After producing 5 leaves, a few growth properties (plant fresh and dry weight, root fresh and dry weight, leaf number and leaf area), biochemical characteristics (amounts of total chlorophyll, proline, soluble proteins, ion leakage and malondialdehyde and activity of Catalase an Proxidase enzymes) and amounts of some elements (K, P, Na, Fe, Zn and Cu) were measured.
Results and Discussion
Based on the results, the simple effect of salinity stress, ascorbic acid and the combined effect of them on ion leakage and amounts of malondialdehyde were significant at the level of 1% probability. Salinity stress increased the amounts of ion leakage and malondialdehyde and application of 5 mM ascorbic acid reduced the amount of these traits to 41.01% and 46.58% compared to the control respectively. The effect of salinity stress, ascorbic acid and the combined effect of them on the concentration of proline and chlorophyll in the leaves of bell pepper were significant at the level of 1% probability. Salinity stress increased the amount of proline but decreased chlorophyll and leaf protein of pepper seedlings and application of 5 mM ascorbic acid increased them to 79.42% and 46.57% compare to control respectively. Under salinity stress the uptake of iron, zinc, copper and phosphorus decreased; using of 5 mM ascorbic acid increasing accumulation of these elements in leaves .On the other hand ascorbic asid could decrease the amounts of sodium accumulation in seedling,s leaves. The results showed that, salinity decreased growth indices (number of leaves, leaf surface, fresh weight of roots and plants) and ascorbic acid reduced the effect of salinity stress on growth parameters. Under salinity stress, 5 mM ascorbic acid treatment increased the leaf surface to 36.30% compared to salinity without ascorbic acid tretment. The effects of salinity stress and the combined effect of salinity stress and ascorbic acid on the amount of catalase and peroxidase enzymes were significant at the level of 1% probability. The effect of ascorbic acid was significant for catalase at 5% probability level and peroxidase at 1% probability level. Although salinity increased the amounts of the antioxidant catalase and peroxidase enzymes but ascorbic acid could increased the activity of them in saline condition.
Conclusion
It seems that application of ascorbic acid as an antioxidant could reduce the effects of salinity stress by increasing the activity of catalase and peroxidase enzymes, reducing sodium uptake and increasing the uptake of phosphorus, potassium, iron, zinc and copper. These could have positive effects on the growth parameters of bell pepper seedlings in salinity conditions. Generally, on based of obtained results, spraying 5 mM Ascorbic acid on bell pepper seedlings modified the resistance of them in salinity stress conditions.
E. Rajabipour; M. Raghami; H.R. Karimi; R. Salehi
Abstract
Introduction: Varieties of melons have long been the most important crops in Iran and have a special place in Iran's agricultural economy which is the third major producers in the world. Different types of melons belong to various botanical groups of Cucumis melo. Salinity stress is one of the limiting ...
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Introduction: Varieties of melons have long been the most important crops in Iran and have a special place in Iran's agricultural economy which is the third major producers in the world. Different types of melons belong to various botanical groups of Cucumis melo. Salinity stress is one of the limiting factors in the production of crops. Majority lands in Iran have arid and semi-arid conditions. The characteristics of these regions are high evaporation and low rainfall, which causes the accumulation of different salts in the surface layer of the earth. Salinity is one of the most important issues in the world, and millions of tons of salt are come annually from irrigation water into agricultural land. Therefore, many plants are encountered to saline soils. Grafting is developing as a new and effective way to increase the tolerance of plants to salinity in advanced countries. Several reports indicate that the rootstock type has a significant role in the resistance of the scion to environmental stresses. In the present study, salinity tolerance of two Iranian melon accessions (‘Garmak’ and ‘Samsouri’) were investigated based on eco-physiological traits, on three commercial rootstocks and a local variety of cucurbit, as well as comparing them with non-grafting plant of ‘Garmak’ and ‘Samsouri’,.
Materials and Methods: This experiment was conducted as factorial in a completely randomized design with three factors including salinity stress (in three levels) and four rootstocks and two scions with three replications in greenhouse and field of the faculty of agriculture, Vali-e-Asr University of Rafsanjan, Iran. In this study, two melon accessions (‘Garmak’ and ‘Samsouri’) were grafted on commercial hybrids rootstocks (‘Ferro’, ‘Shintozwa’ and ‘Ergo’) and a local variety of bottle gourd and subjected to salinity treatments (0, 20 and 40 mM levels of sodium chloride) in the field. One month after adaptation of grafted plants, grafted and non-grafted plants were transferred to the field and salinity treatment (sodium chloride) was applied one week after planting in the field. The evaluated traits at the end of the experiment were: photosynthetic parameters (total chlorophyll, total carotenoids, photosynthetic efficiency index), relative water content, vascular pressure potential, proline and soluble sugars.
Results and Discussion: The results showed that in salinity treatments, grafted plants were superior to non-grafted plants in studied traits. Differences were also observed between the tested rootstocks, so that the ‘Ergo’ hybrid was weaker in many features than other rootstocks and even non-grafted plants. The results showed that salinity increased the amount of proline and carotenoids in the leaf, which was lower in grafted than non-grafted plants. With increasing salinity, the pressure of vascular pressure decreased. This amount was lower in non-grafted than in plants grafted on ‘Ferro’ and ‘bottle gourd’. Also, the total chlorophyll content and relative water content of leaf decreased, which this reduction was higher in non-grafted plants. Among the traits mentioned, the best studied rootstocks were ‘Ferro’ and ‘Shintozwa’ that were better than other rootstocks as well as non-grafted plants. By increasing salinity, the soluble sugars of grafted plants on ‘Ferro’ and ‘bottle gourd’ decreased, but in grafted plants on ‘Shintozwa’ hybrid, increased salinity increased the soluble sugars content.
Conclusions The results of this study showed that salinity stress significantly reduced the relative water content of leaves, photosynthetic pigments and carotenoids. Salinity also increased the potency of vascular pressure potential and proline concentration. Compared to non-grafted plants, the negative effects of salinity stress on non-grafted plants were more prominent than grafted plants. Also, the amount of photosynthetic parameters in grafted plants decreased less than non-grafted plants. Comparing the two evaluated accessions, ‘Samsouri’ was more appropriate than stress conditions. Compared to non-grafted and grafted plants in non-stress conditions, the best rootstock was ‘Ferro’, which showed the best result for all traits except for proline content in both ‘Samsouri’ and ‘Garmak’. At a salinity level of 40 mM, the ‘Ferro’ and ‘Shintozwa’ were superior to other rootstocks, which showed satisfactory results in most traits. Also, due to the poor reaction of the grafted plants on the bottle gourd rootstock under salt stress conditions, it seems that this rootstock probably due to low compatibility is not a suitable rootstock for two evaluated accessions in the present study. Based on the findings of the present study, ‘Ferrero’ and Shintozwa’ in combination with ‘Samsouri’ and ‘Garmak’ showed more tolerance to salinity.
Hamid Alipour; Mohammad Kafi; Ahmad Nezami; Amir hossein mohammadi
Abstract
Introduction: In Iran, main pistachio cultivation areas are located in the edge of desert. The major problem of these areas is the salinity of soil and irrigation water, which affects the growth and performance of plants and reduce yield.
Material and methods: In the present study, the effects of salinity ...
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Introduction: In Iran, main pistachio cultivation areas are located in the edge of desert. The major problem of these areas is the salinity of soil and irrigation water, which affects the growth and performance of plants and reduce yield.
Material and methods: In the present study, the effects of salinity on growth characteristics and mineral contents of seedlings of seven pistachio cultivars and three genotypes (Akbari, Ahmad-Aghaei, Kaleh-Ghoochi, Fandoghi, Badami, Ebrahimi, Seyfadini and G1, G2 and G3 genotypes) were evaluated. The study was conducted in split plot based on randomized complete block design in three replications. The main plots were salinity levels of the irrigation water (0.6, 15 and 30 dS/m) by adding sodium chloride to tap water, and the sub plots were the pistachio cultivars. After germination of seeds in the lab, the seedlings were transplanted into new vases in the greenhouse. At 3rd leaf stage, the salinity treatments were imposed for a period of four months. At the end of the experiment, all samples were collected for growth and cation contents of shoots and roots and data were analyzed by analysis of variance and correlation method, using SAS statistical software and Duncan’s Multiple Range Test was employed at probability level of 5%.
Results and discussions: The results showed that increasing salinity levels reduced stem, root and leaf dry weight as well as stem height and diameter. Salinity also caused a reduction in leaf number and leaf area. At the salinity level of 30 dS/m, dry weights of root and leaf decreased by more than 70%. The length and diameter of seedlings were decreased by 17.2 % and 37.9 % under the mentioned condition. According to the measured growth characteristics, Akbari and Kaleh-Ghoochi, considered as fast growing cultivars, while G3 genotype and Seyfoddini cultivar were considered as slow growing cultivars. By increasing salinity, sodium and calcium concentrations in root, stem and leaf increased significantly, and the ratio of potassium to sodium decreased in the mentioned parts of the plant. Fandoghi and Kaleh-Ghoochi cultivars accumulated the highest amounts of sodium in leaf, while G1 and G2 genotypes had the lowest sodium level. An important fact is that G3 variety had minimum stem and leaf sodium content and maximum root sodium content. In contrast, Kaleh-Ghoochi cultivar had maximum leaf sodium content and minimum root sodium content. This obviously indicates that G3 variety accumulates sodium in the root and avoids sodium transmission to stem and leaf, and Kaleh-Ghoochi variety acted conversely. G2 genotype and Kaleh-Ghoochi variety contain the highest (3%) and lowest (1.4%) levels of leaf potassium. At salinity levels of 15 and 30 dS/m, the index of potassium to sodium ratio decreased by 93% and 87%, respectively, in comparison to the control salinity level (0.6 dS/m2). Generally, local genotypes of pistachio (G1, G2 and G3) showed lower sodium absorption and transport to leaf, while G3 genotype had the highest sodium content in the root and the lowest concentration of sodium in stem and leaf. G2 genotype and Ahmad-Aghaei cultivar had the highest leaf potassium to sodium ratios of 7/8 and 6/3, respectively, while Kaleh-Ghoochi cultivar had the lowest leaf potassium to sodium ratio (3/95). It seems that Kaleh-Ghoochi, Fandoghi and Akbari cultivars are relatively sensitive and G1, G2 and G3 genotypes and Ahmad-Aghaei cultivar are relatively tolerant to salinity at seedling stage. Results of correlation analysis showed a significant negative correlation between the levels of salinity and growth characteristics of pistachio. Leaf sodium content has a significant negative correlation with leaf potassium content as well as the potassium to sodium ratio in root, stem and leaf. Reduced or stunted growth of the pistachio seedlings can be a result of water stress as well as sodium and chlorine toxicities. The impaired balance of nutrient uptake through the root in salt stress conditions leads to reduced growth characteristic of the pistachio seedlings. As the salinity of the irrigating water increases, concentrations of sodium and chlorine ions in soil solution increases, therefore, balance of nutrients is impaired and the root absorption of sodium and chlorine increases and potassium uptake decreases. Hence, the concentrations of sodium and chlorine ions increased in root, stem and leaf, andpotassium concentration decreased. Salinity tolerance in many plants is attributed to non-transmission or limited transmission of sodium to aerial parts of the plant. Various pistachio cultivars acted differently in absorption and accumulation of these elements in the parts of plant. The pistachio varieties with less sodium absorption and transmission to the leaf, but more potassium absorption and transmission, increased potassium to sodium ratio in the leaf and showed more tolerance to salinity. The mechanism is not clearly recognized, perhaps sodium is re-absorbed from the xylem sap and remained in the root and stem, without transmission to leaf. A similar mechanism probably occurs in local genotypes of pistachio (G1, G2, and G3) and results in improved tolerance to salinity.
hassan Farhadi; majid Azizi; hossein Nemati
Abstract
Introduction: Fenugreek (Trigonalla foenum-graecum L.), an annual herbaceous plant belonging to the Coleoidea (Fabaceae) family, has numerous medicinal properties such as decreasing blood glucose, laxative, appetizer, mucus, antipyretic and increasing the amount of milk during lactation . Among the most ...
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Introduction: Fenugreek (Trigonalla foenum-graecum L.), an annual herbaceous plant belonging to the Coleoidea (Fabaceae) family, has numerous medicinal properties such as decreasing blood glucose, laxative, appetizer, mucus, antipyretic and increasing the amount of milk during lactation . Among the most important problems in arid and semi-arid regions, drought stress or water shortage will have negative effects on plant growth. Drought stress occurs mostly because of reducing water availability in the soil. This may be due to excessive water loss or absorption problems, or both of them. One of the major factors limiting germination, which occurs in more arid and semi-arid regions, is salt stress. The study was done to evaluate germination of four Iranian population of fenugreek (Amol, Tabriz, Sari and Mashhad) under drought and salinity stresses.
Materials and methods: To investigate the effect of salinity and drought stresses on germination and seedling growth characteristics of native landrace fenugreek, two separate experiments were conducted in a Completely Randomized Design with three replications in Seed Laboratory of University of Mashhad in 2014. The experiment treatments consisted of four levels of salinity (0, 60, 120, 180 mM) that was induced by different concentrations of sodium chloride and drought stress induced by polyethylene glycol 6000 (PEG 6000) at four levels (0, -3, -6 and -9 Bar) with three replications. The drought stress levels were simulation by polyethylene glycol 6000 and using the Michel and Kaufmann formula. Distilled water was applied as control. Iranian seed population of fenugreek were purchased from the city of Amol, Tabriz, Sari and Mashhad then the seeds were washed with sodium hypochlorite (3 % v/v) for two minutes for disinfestation and washed three times with distilled water. On the twelfth day of experiment, seedling traits such as plumule and root length and weight in Petri dishes were measured.
Results and Discussion: The results of ANOVA showed that salinity and drought stress significantly (p≤0.01) affect germination process. The results of the means comparison confirmed that fenugreek germination in all seed population was reduced by increasing salinity levels. The lowest germination was detected under 180 mM salt stress in “Tabriz” population (12.04%), while the highest germination (95/26%) was calculated in “Mashhad” population at control. Seeds of “Mashhad” population in comparison to other population showed higher germination at other salinity levels. Germination rate also was significantly affected by salinity (p≤0.01). Decreasing of germination rate in fenugreek population of Amol, Tabriz, Sari and Mashhad under 180 mM salinity stress in comparison to control (0 mM) were 84/62, 87/80, 85/93, 82/59, respectively. Mashhad and Amol (second order) populations showed more germination rate stability after changes in salinity levels. The results of analysis of variance from this study showed that interaction effect of salinity and population significantly (p≤0.05) affect root length of the fenugreek. The root length of Mashhad and Amol populations were more stable at high level of salinity. Other researcher also reported that the root length decreased after salinity treatments (10, 13). Salinity stress affect water absorption by seed and decreasing Amylase and lipase activity caused degradation of stored material in seeds and then decreasing root length (23). Salinity, population and interaction between these factors significantly (p≤0.01) affected length of plumule. The results showed that Mashhad population had the highest and Tabriz revealed the lowest length of plumule. Interaction effects of treatments on seedling dry weight showed significant (p≤0.01) differences. Mashhad in comparison to the other populations had the highest seedling dry weight as 9.26, 8.10, 7.22 and 3.6 mg/seedling at different salinity treatments (0, 60, 120, 180 mM), respectively.
Interaction effects of drought stress and population on germination percentage was significant (p≤0.01). Mashhad and Amol (second order) populations were the best populations. At the highest level of drought stress (-9 Bar), these two populations had the lowest decrease in germination percentage. The mechanism of the results was the same as salinity which explained in above. According to the results of analysis of variance (ANOVA), all treatments and all interaction had significant effect (p≤0.01) on germination rate. The Mashhad and Sari populations were more tolerant than other populations against drought stress examined as germination rate as concerned. Analysis of variance showed that the simple effects of drought stress and population on root length were significant at one percent but interaction effect of drought stress and population was not significant statistically. The root length was in the range of 26.78 to 50.29 mm in the tested population. Mashhad population was more tolerant against drought stress in comparison to the other tested populations. Analysis of variance showed that simple effect of drought and population were significant (p≤0.01) on this trait but their interaction was not significant. Length of plumule mean comparison showed that the traite was in the range of 21.74 to 43.31 mm in Tabriz and Mashhad populations, respectively.Acoording to the length of plumule,Mashhad population in comparison to other tested populations under drought stress was tolerant . The water potential (drought stress), population and interaction between them showed significant effect (p≤0.01) on seedling dry weight. Among the evaluated population the Mashhad population was tolerant to drought stress when seedling dry weight was concerned. The highest correlation coefficient (r=0.96) was detected between germination percentage and root length and in second order the correlation coefficient between germination percentage and seedling dry weight was 0.93. The lowest correlation coefficient (0.61) was observed between germination rates and seedling dry weight.
Conclusions: The decline in germination percentage, germination rate, root length, shoot length and dry weight of seedlings with increased water osmotic potential in Mashhad population was less than other evaluated populations. Seed germination rate was more sensitive than seed germination percentage in both salt and drought stress therefore this trait is a suitable criterion for screening of tolerant population for future breeding purpose. The order for tolerance to salinity and drought stress in evaluated population was Mashhad, Tabriz, Sari and Amol.
M. Goldani; E. Keshmiri
Abstract
Introduction: Salinity has been recognized as one of the major abiotic factors affecting crop yields in arid and semi-arid irrigated areas of the world and efforts for breeding salt-resistant crop plants have been made. Approximately one-third of the world irrigated soils and a large proportion of soils ...
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Introduction: Salinity has been recognized as one of the major abiotic factors affecting crop yields in arid and semi-arid irrigated areas of the world and efforts for breeding salt-resistant crop plants have been made. Approximately one-third of the world irrigated soils and a large proportion of soils in dry land are saline. Two major effects have been identified as the probable causes of high salt toxicity in crop plant i.e., the ionic effect and the osmotic effect. The ionic effect results in alterations in enzymatic processes, disturbances in accumulation and transport of different ions or a combination of all these factors. As a result, shoot and root growing reduce and uptake of nutrient elements by plants is adversely affected. While excess Na accumulated in plants under salinity stress conditions hinders K uptake; Cl hinders NO3 uptake by plants and destroys ionic balance in plants. Evening primrose is a plant which belongs to Onagraceae. Its seed oil has a special arrangement in Glycerol molecule, so it has been used a lot in medical treatments and also feeding. Researchers showed that using the best techniques and methods in farming can increase the amount of oil in the seeds of this plant. The wrong method of agricultural activities in Iran caused increasing salt in the soil, so growing plants in this situation isn’t possible. For confronting with this phenomenon knowing and choosing kinds of plants that can resist the situation of salt is really a necessary.
Materials and Methods: This study was conducted as a factorial experiment based on completely randomized design with three replicates was performed with five levels of NaCl salinity on Oenothera macrocarpa (0, 30, 60, 90 and 120 mM) and potassium chloride levels (zero and 15.02 mM) and three times in the Faculty of Agriculture, Ferdowsi University of Mashhad in 1390. Salt treatment to prevent osmotic shock was applied to four-leaf stage and treated with potassium was gradually simultaneously with irrigation water applied. 6 weeks after the treatments, the rate of photosynthesis, chlorophyll relative content and stomata conductance was measured. The analysis of variance was estimated using SAS software. The statistical comparison was done by Duncan's multiple range tests. Charts were drawn using Excel software.
Results and Discussion: According to the result of the analysis of variance, increasing the density of sodium chloride in the planting areas had a special effect on the size of the leaves and the weight of dried plant and the weight of each leaf and dried root. This effect showed a meaningful variation between the weight of dried leaves and its dried root and shoots. The salty areas have a lot of negative ions like Magnesium, Chlorine, sodium and sulfate. These materials are harmful by themselves or cause effective disorder in the plants metabolism. Salinity treatments applied to significant influence (01/0> p) on the characteristics of photosynthesis, stomata conductance and numbers were read out by spade. For example, sodium and potassium competition and competition between chlorine and nitrate impairs the absorption of nutrients. The result of this reaction is that the plant needs more energy for producing organic matter so it loses most of its energy to resist against salt. This situation of the plant causes a low activity of the root and the growing of the shoot consequently reduce. At this situation the weight and length of the plant reduce too. For example existing potassium in salty lands cause the reduction of sodium in the shoot of the plants. This research was done in a pot with the same amount of salt. Potassium causes the reduction of Toxicity effects of sodium. Research has shown that the potassium in regulating osmotic pressure and permeability of plant cell membranes is effective and cause Increase plant tolerance to salinity.
Conclusion: Some biological indexes of evening primrose plant were negatively affected by increasing rates of NaCl and KCl applications. In salty condition, increasing the amount of sodium causes the reduction of potassium, comparing with sodium. As a matter of fact, this kind of reaction causes the reduction of potassium comparing with sodium. We know that potassium causes a suitable osmotic pressure and reduce the destructive effect of oxidation. So having more potassium than sodium in salty lands is known as the standard resistance. NaCl and KCl compounds should be applied in a precise amount to evening primrose. Otherwise, quantity and quality of evening primrose plant will be decreased.
B. Golein; V. Rabiei; F. Mirabbasi; Reza Fifaei; M. F. Halaji Sani
Abstract
Introduction: Citrus (L.) is a large genus that covers several major cultivatedspecies, including Citrussinensis (sweet orange), C.reticulata (tangerine and mandarin), C. limon (lemon), C.grandis (pummelo), and C. paradisi (grapefruit).Citrus is one of the world’s important fruit crops and grown inmost ...
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Introduction: Citrus (L.) is a large genus that covers several major cultivatedspecies, including Citrussinensis (sweet orange), C.reticulata (tangerine and mandarin), C. limon (lemon), C.grandis (pummelo), and C. paradisi (grapefruit).Citrus is one of the world’s important fruit crops and grown inmost areas with suitable climates between latitude 35◦N–35◦S. InIran, citrus industry is of paramount importance. Citrus species have been classified as salt-sensitive crops, although their relative tolerance can be influenced by climate, fertilization, soil type, irrigation method and rootstock. Citrus rootstocks differ in their ability to exclude Cl−and/or Na+from the scion. Many authors have contrasted the relative abilities of rootstocks to restrict movement of salts to the scions. The rootstocks Cleopatra mandarin (C. reshni), Rangpur lime (C. limonia) and Severiniabuxifolia (Poir) Tenore were relatively effective in restricting Cl−transport to scions, whereas the rootstocks Swingle citrumelo and Carrizo citrange were found to be less restrictive. Although the mechanism by which some rootstocks reduce concentrations of ions in the scion is still unknown, it seems to depend on the vigor of the scion and on water requirements. There are a number of reports demonstrating that both scion and rootstock may influence Cl−accumulation in leaves. Several papers reported that accumulation of Na+ in shoots seemed to be more dependent on rootstock–scion combinations. Since, citrus species are different in salt tolerance and use of tolerant rootstocks can decrease salinity damages, sothis study was conducted to identify tolerant genotypes among unknown types from the Kotra Citrus Research Station, Citrus and Sub-Tropical Fruits Research Center (Ramsar).
Materials and Methods: The experiment was –arrangedin afactorial, based on completely randomized design in three replications with two plantsin each experimental unit in Iran Citrus Research Institute.Treatment included 10 citrus natural genotypes along with two varieties of Cleopatra mandarin (tolerant plant) and Swinglecitrumelo (sensitive plant) with six-month old and four salinity levels of sodium chloride: 0(control), 2, 4 and 6 dsm-1, for 16 weeks in the greenhouse condition. Effect of salinity on fresh and dry weight of shoot and root, relative water content (using upper leaves), stomatal density (with counting of stomata using microscope), concentration ofCl (with titration method of silver nitrate) and Na (by flame photometry) in roots and leaves, content of total chlorophyll (using acetone 80%), proline (spectrophotometry at wavelength of 520 nm), lipid peroxidation (spectrophotometry at wavelength of 532 nm) and activity of peroxidase enzyme (spectrophotometry at wavelength of 470 nm)were investigated. Data analysis was done by SAS 9.1 software.
Results and Discussion: The results indicated that, the interaction of genotypes and salinity levels hadnot significant difference in relative water content, stomatal density and Na+concentration - in roots but, other traits except total chlorophyll content which was significant at 5% level, were significant at 1% level. Shoot fresh and dry weight of genotypes No. 4 and 6 were significantly (P
V. Rouhi; A. Nikbakht; Sadollah. Hooshmand
Abstract
Introduction: Pomegranate (Punica granatum L.) belong to Punicaceae family is native to Iran and grown extensively in arid and semi-arid regions worldwide. Pomegranate is also important in human medicine and its components have a wide range of clinical applications. Cracking causes a major fruit loss, ...
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Introduction: Pomegranate (Punica granatum L.) belong to Punicaceae family is native to Iran and grown extensively in arid and semi-arid regions worldwide. Pomegranate is also important in human medicine and its components have a wide range of clinical applications. Cracking causes a major fruit loss, which is a serious commercial loss to farmers. Fruit cracking, seems to be a problem that lessens the marketability to a great extent. Fruit cracking is one of the physiological disorders wherever pomegranate trees are grown. It may be due to moisture imbalances as this fruit is very sensitive to variation in soil moisture prolonged drought causes hardening of skin and if this is followed by heavy irrigation the pulp grows then skin grows and cracks. Many factors i.e., climate, soil and irrigation, varieties, pruning, insects and nutrition statues influence the growth and production of fruit trees. Deficiencies of various nutrients are related to soil types, plants and even to various cultivars. Most nutrients are readily fixed in soil having different PH. Plant roots are unable to absorb these nutrients adequately from the dry topsoil. Foliar fertilization is particularly useful under conditions where the absorption of nutrients through the soil and this difficult situation to be present in the nutrients such as calcium. Since the calcium element is needed, so spraying them at the right time is correct way to save the plant requirements. Therefore, a research conducted on effect of sodium chloride concentrations and its foliar application time on quantitative and qualitative characteristics of pomegranate fruit (Punica granatum L.) CV. “Malas Saveh”.
Materials and Methods: An experiment conducted at Jarghoyeh, Esfahan, Iran in 2012. The factors were Sodium chloride (0, 5 and 10 g/L) and times of spray (15, 45 and 75 days before harvest). The study was factorial experiment in the base of randomized complete blocks design with three replications. The measured traits were cracking and sun scald percentage, seed dry and fresh weight, total fruit weight, vitamin C and titratable acidity (TA) using titration method, total soluble solids (TSS) using hand refractometer, skin fruit firmness using hand penetrometre, pH using pH meter and dry material. Data analyzed using SAS and MSTAT-C statistical program and means compared using an LSD test (p < 0.05).
Results and Discussion: Analysis of variance showed that calcium chloride had significant effect on creaking percentage. Mean comparison was conducted using LSD range test (at 5% level). Sodium chloride decreased cracking percentage compared to control. Different stages of sodium chloride application show significant effect on cracking percentage. Sodium chloride decreased the cracking rate by increasing of its concentrations. Effect of calcium chloride was significant on sun scald. The lowest sun scald occurred inthe second time and the highest in the third time of calcium chloride spraying. The effects of sodium chloride at different stages and concentrations were significant on the total fruit weight and seed fresh weight. The highest total fruit weight and seed fresh weight obtained in the first time and the lowest in the third time of calcium chloride spraying. The effects of sodium chloride at different stages and concentrations were significant on the skin firmness. The highest skin firmness obtained in the third time of calcium chloride spraying and 10 sodium chloride concentrations and the lowest in the first time of calcium chloride spraying and control. The time of calcium chloride spraying had significant effect on total acidity, pH and vitamin C. The highest and lowest fruit total acidity and pH obtained in first and third time of calcium chloride spraying, respectively. However, the highest and lowest fruit vitamin C observed in third and first time of calcium chloride spraying, respectively. Fruits treated with Sodium chloride showed a reduction in vitamin C and fruit firmness, but increased total soluble solids (TSS). In fruit traits increased by higher sodium concentration and earlier spraying time. In addition, later spraying time increased fruit skin firmness conclusion sodium chloride decreased cracking and sun scald percentage Quantitative.
Conclusion: In conclusion, higher sodium chloride concentration reduced fruit creaking and sun scald. In addition, earlier time and higher sodium chloride concentration caused improve quantitative fruit traits. Finally, skin firmness increased with higher sodium chloride concentration and later spraying time.
M. Babalar; J. Hashemi; Y. Mostufi
Abstract
Sulforaphane is a strong anticarsenogen compound which is produced in broccoli. It seems salt stress improves sulforaphane production via systemic acquired resistance. To obtain suitable salt concentration and for having more content of sulforaphane with controlling germination percentage, NaCl in 5 ...
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Sulforaphane is a strong anticarsenogen compound which is produced in broccoli. It seems salt stress improves sulforaphane production via systemic acquired resistance. To obtain suitable salt concentration and for having more content of sulforaphane with controlling germination percentage, NaCl in 5 levels 0, 50, 100, 150, 200 mM (0, 4.53, 9.125, 13.68, 18.25 dS/m ) and salicylic acid in 3 levels (0,100, 200 µM) were examined. A logistic regression model was used to assess the effects of treatments on the maximum cumulative germination percentages, rate of increase, and germination lag times. Sulphoraphan and vitamin C were determind by HPLC method. Combination between salicylic acid and chloride sodium improved sulforaphane concentration. The 100 µM salicylic acid with 100 mM chloride sodium was the best treatment as the highest concentration of sulforaphane and vitamin C with perfect growth factors achieved in the treatment.
