Pomology
Farhad Azarmi-Atajan; Mohammad Hossein Sayyari Zahan; Abdollah Mirzaei
Abstract
IntroductionPhosphorus (P) is one of the most important nutritional elements of plants and it is necessary for the development of plant roots. Due to the high cost of chemical fertilizers, it is important to use cheap sources such as rock phosphate (RP) to supply P needed by plants. The efficiency of ...
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IntroductionPhosphorus (P) is one of the most important nutritional elements of plants and it is necessary for the development of plant roots. Due to the high cost of chemical fertilizers, it is important to use cheap sources such as rock phosphate (RP) to supply P needed by plants. The efficiency of RP is low and its use alone cannot supply the P required by the plant. One of the ways to increase the efficiency of RP is to use phosphate solubilizing bacteria (PSB). Considering the salinity of soil and irrigation water in many pistachio-growing areas of Iran, the use of salt-resistant PSB can increase their resistance to salt stress in addition to supplying the P required by pistachios. Materials and MethodsIn order to investigate the role of PSB in supplying the required P of pistachio seedlings under saline conditions, a factorial experiment was conducted in the form of a completely randomized design with 3 replications in greenhouse conditions. The factors included PSB at three levels [control (PSB0), Pseudomonas sp. 1 (PSB1) and Pseudomonas sp. 2 (PSB2)], RP at two levels (0 and 30 mg P from rock RP) and irrigation water salinity at three levels (0, 5 and 10 dS/m). The bacteria used in this study were able to produce ACC-deaminase, indole acetic acid and dissolve tricalcium phosphate in vitro. For inoculation, inoculum containing each bacterium with a population of 108 cells/ml was prepared in the nutrient broth medium and each pistachio seed (P. vera L. cv. Badami) was inoculated with 500 µL of bacterial inoculum. The plants were irrigated with non-saline water for four weeks and then with saline water until harvesting based on experimental treatments. During the growth period, the soil moisture of the pots was kept at about 80% of the field capacity by weight method. Finally, shoot and root sampling was performed and various characteristics such as shoot and root dry weight, chlorophyll, carotenoids, proline, soluble sugars, RWC, MSI and phosphorus as well as sodium concentrations were measured. Analysis of variance of traits was performed using SAS software and the means were compared using the LSD method with a probability level of P≤0.05. Results and DiscussionThe results showed that water salinity decreased the dry weight of shoot and root, chlorophyll a, chlorophyll b, carotenoids, relative water content (RWC) and membrane stability index (MSI) of leaf and p concentration of shoot and root of pistachio seedlings. Auxin produced by bacteria can directly increase cell division and growth or indirectly increase ACC-deaminase production. On the other hand, proline, soluble sugars and sodium were accumulated in the leaves of seedlings with increasing water salinity. According to the results, although the use of RP alone did not show significant effect on the studied indicators, its simultaneous use with PSB had the greatest role in improving the growth of pistachio seedlings, especially in saline conditions. The highest amount of dry weight of shoot (1.89 g.plant) and root (1.59 g.plant), chlorophyll b (1.30 mg/g fresh weight), carotenoids (1.35 mg/g fresh weight), soluble sugars (59.1 mg/g fresh weight), proline (36.7 mg.g-1 fresh weight), leaf RWC (91 %), leaf MSI (84%) and the P concentration of shoot (0.39 %) and root (0.35 %) was obtained from the simultaneous application of RP and PSB (especially PSB2) in non-saline conditions. The PSB increase soil P availability by reducing of soil pH by release of protons and organic acids and mineralization by production of acid phosphatases. Bacteria, in addition to increasing soil P availability, improve phosphorus uptake and chlorophyll content in plants by affecting root morphology and its development in soil. On the other hand, inoculation with PSB (both separately and together with rock phosphate) reduced sodium accumulation in the aerial parts and roots of pistachio seedlings. ConclusionUnlike pistachio trees, the tolerance of pistachio seedlings to salt stress is low. According to the results, the salinity symptoms were visible in the pistachio seedling leaves at the water salinity level of 10 dS/m, which caused the drying of the lower leaves and the burning of the edges of the young leaves. On the other hand, although the application of RP alone did not have significant effect on increasing the tolerance of plants to salt stress, the simultaneous use of RP with PSB increased growth, the accumulation of proline and soluble sugars, the concentration of chlorophyll and carotenoids, the amount of RWC and MSI and P concentration of pistachio seedlings, especially in saline conditions. Therefore, the use of PSB can help the growth and establishment of pistachio seedlings under salinity stress conditions and increase the efficiency of RP and supply P needed by the seedlings.
Growing vegetables
Jaber Panahandeh; Mohammad Sedigh Zare far; Alireza Motallebi-Azar; Fariborz Zare Nahandi; Mina Amani
Abstract
IntroductionVarious methods of stress directly affected the growth and production yield of numerous plants. For example, environmental stress reduces the tomato manufacturing by the disrupting its natural metabolism, or, salinity stresses affect the it is growth and development from the germination stage ...
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IntroductionVarious methods of stress directly affected the growth and production yield of numerous plants. For example, environmental stress reduces the tomato manufacturing by the disrupting its natural metabolism, or, salinity stresses affect the it is growth and development from the germination stage to the fruit ripening stage. Salinity in tomatoes by stimulating the biosynthesis of growth regulators such as ethylene and abscisic acid leads to the acceleration of the aging of the leaves. Therefore, development of different methods to induce salinity stress tolerance in plants is necessary. Some approaches were studied to develop the salinity tolerant plants such as genetic breeding, environmental improvements and usage of phytohormones and signal molecules. Salicylic acid or orthohydroxybenzoic acid plays an important role in regulating the physiological and biochemical responses of plants to stress conditions, which improves the plant's resistance to adverse environmental conditions. For instance, salicylic acid is a facile and effective way to increase plant productivity under salt stress conditions. Considering the positive effects of salicylic acid in modulating the effects of salinity, this study was conducted with the aim of investigating the effects of salicylic acid’s usage in modulating the harmful effects of salinity on some vegetative, physiological, quantitative and qualitative characteristics of two tomato cultivars of Baneh local mass and Semi Dwarf line.Materials and MethodsTo investigate the effect of salicylic acid in modulating the effects of salinity stress in tomato, a factorial experiment was conducted in the form of a randomized complete block design, with 12 treatments, in 3 replications and with a total of 36 experimental units in the hydroponic greenhouse of the Department of Horticulture, Faculty of Agriculture, and university of Tabriz. The treatments included two levels of salicylic acid (0 and 1 mM) and salinity levels (0, 35 and 70 mM NaCl) on two tomato cultivars of Baneh and Semi Dwarf.Results and DiscussionThe results showed that in Baneh and Semi Dwarf cultivars, the increase in salinity levels caused a decrease in vegetative indices, meanwhile the treatment of salicylic acid along with salt stress increased same indices. Also, salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. By examining the qualitative indicators, it was observed that titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the amount of proline increased at different salinity levels with salicylic acid treatment, but the amount of leaf chlorophyll index decreased with the increase of same condition.ConclusionThe results of testing the effect of salicylic acid and the effects of salinity stress on vegetative, quantitative, qualitative and physiological indicators in Baneh and Semi Dwarf tomatoes showed a remarkable difference in terms of significance. In terms of vegetative traits; Plant height, leaf area index, shoot wet in Baneh and Semi Dwarf cultivars decreased with increasing salinity levels of vegetative indices, but salicylic acid treatment along with salinity stress increased same indices. Indicators such as yield, fresh weight of fruit, and percentage of dry matter of fruit showed different responses to different levels of salinity and salicylic acid treatment. The fresh weight of fruit increased with the application of salicylic acid. Also, salt stress caused an increase in the percentage of dry matter of the fruit. But salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. In terms of quality indicators; the amount of titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the level of proline increased across various salinity levels with salicylic acid treatment. However, the leaf chlorophyll index decreased with rising salinity levels, even in the presence of salicylic acid treatment. Overall, salinity stress caused a decrease in most analyzed traits in the Baneh and Semi Dwarf cultivars. Nevertheless, it led to improvements in certain quality traits. Additionally, salicylic acid treatment enhanced the mentioned indices in most of the examined traits in both cultivars. Therefore, considering the positive effects of salicylic acid treatment on Baneh and Semi Dwarf cultivars under salinity stress conditions, its use is recommended.
Medicinal Plants
Saeid Daghighi; Farhad Azarmi-Atajan; Nasibeh Chopani Aghech
Abstract
Introduction
Barberry is one of the important agricultural products of Iran and has an important role in the economy of farmers, especially in South Khorasan province. Salinity as abiotic stress can cause an ionic or osmotic imbalance in plant cells. Salt stress also restricts plant growth and ...
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Introduction
Barberry is one of the important agricultural products of Iran and has an important role in the economy of farmers, especially in South Khorasan province. Salinity as abiotic stress can cause an ionic or osmotic imbalance in plant cells. Salt stress also restricts plant growth and development by affecting water reducing availability and affecting plant production. Despite the relatively high tolerance of barberry to environmental stresses, increasing soil salinity and irrigation water in barberry growing areas, the growth, and yield of this agricultural product have decreased. The use of plant growth-promoting rhizobacteria (PGPR) is a new method that has been shown to increase the tolerance of various plants to salinity stress.
Materials and Methods
Due to the lack of information about the effect of salinity on the growth and establishment of barberry off-shoot and the role of beneficial soil bacteria in increasing the tolerance of this plant to salinity stress, this study aimed to investigate the role of bacteria on growth, physiological and biochemical properties and uptake of nutrients by barberry off-shoot at different levels of irrigation water salinity. For this purpose, a factorial study was conducted in a randomized complete block design with 3 replications. Experimental factors included plant growth-stimulating bacteria at three levels (control (Without inoculation) and inoculation with Pseudomonas sp. P1 and Pseudomonas sp. P2) and salinity of irrigation water at three levels (control, 6 and 12 dS/m from sodium chloride source). The bacteria used in this study were able to produce indole acetic acid, siderophore, ACC deaminase enzyme, and dissolve insoluble phosphate (tricalcium phosphate) in vitro. For inoculation, inoculum containing each bacterium with a population of 108 cells/ml was prepared in the Nutrient Broth medium and added to the root medium. The plants were irrigated with non-saline water for one month and then with saline water for two months based on experimental treatments. Finally, leaf sampling was performed and various characteristics such as leaf dry weight, chlorophyll, proline, total sugar, RWC and phosphorus, potassium, sodium, and chloride concentrations were measured. Analysis of variance of traits was performed using SAS software and the means were compared using the LSD method with a probability level of P≤0.05.
Results and Discussion
The results showed that the salinity of irrigation water reduced leaf dry weight, chlorophyll and carotenoid concentration, relative water content, and potassium to sodium ratio of barberry leaves. Decreased photosynthetic pigments under salinity may be due to decreased synthesis of the main chlorophyll pigment complex, oxidative damage to chloroplast lipids, pigments, and proteins, or increased chlorophyllase activity. In contrast, with increasing salinity, the amount of proline and total sugar and the concentration of phosphorus, sodium, and chlorine in leaves increased. Bacterial inoculation also increased leaf dry weight, chlorophyll, carotenoids, potassium concentration, relative water content, and potassium to sodium ratio, especially in saline conditions. Also in saline conditions, the concentrations of sodium, chlorine, phosphorus, proline, and total sugar in the leaves of barberry off-shoot inoculated with bacteria decreased. It seems that PGPR plays a significant role in the regulation of cellular osmolites, including proline and soluble sugars, by producing various metabolites and increasing the absorption of water and nutrients. The highest amount of leaf dry weight (0.70 g), total chlorophyll (0.92 mg g-1 fresh weight), carotenoids (0.51 mg g-1 fresh weight), leaf potassium (0.48 %), and total leaf sugar (43.7 mg g-1 dry weight) was obtained from the application of PGPR in conditions without salinity stress. Also, the use of bacteria in saline conditions decreased the amount of phosphorus and total sugar and in non-saline conditions increased the amount of these parameters. PGPR through various mechanisms such as the production of auxin, organic and mineral acids, and secretion of proton and phosphatase enzymes increase the availability of phosphorus for the plant, root growth, and absorption of water and nutrients. Increased absorption of water and nutrients has led to increased leaf growth and development and therefore reduced phosphorus concentration (dilution effect).
Conclusion
According to the results, PGPR by increasing the absorption of water and nutrients such as phosphorus and potassium caused osmotic regulation in the plant and thus increased the tolerance of barberry off-shoot to salinity stress of irrigation water. The ability of these bacteria to improve plant growth in saline conditions could be due to the production of auxin, siderophore, dissolution of tricalcium phosphate, and especially the production of the enzyme ACC-deaminase (as observed in vitro). Therefore, these bacteria can be used to improve the nutrition growth and establishment of barberry off-shoot.
Ali Momenpour; Ali Imani; Davoud Bakhshi; Hamed Rezaie
Abstract
Introduction: Almond (Prunus amygdalus B.) is one of the most important crops consumed as a dry fruit and it is mainly adaptable to arid and semi-arid regions mostly suffering from salinity stress (8). Soils with dry humidity regime are dominant in Iran and in the world at large and mostly include regions ...
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Introduction: Almond (Prunus amygdalus B.) is one of the most important crops consumed as a dry fruit and it is mainly adaptable to arid and semi-arid regions mostly suffering from salinity stress (8). Soils with dry humidity regime are dominant in Iran and in the world at large and mostly include regions with more evaporation than precipitation. This in turn leads to increased salinity of the soil (9 and 10). Based on available reports, roughly 12.5% of land areas in Iran are saline, which overwhelmingly contain sodium, while more than 800 million hectares of land area on the earth (6% of overall global land area) are affected by salinity (9 and 10). Therefore, compound of rootstock and scion may be used as one of the influence factors in sensitivity or tolerance to salinity of planted fruit trees including almonds (8 and 11). In recent years, for various reasons including the uniformity of trees, instead of sexual rootstock, vegetative rootstock is used. Rootstock GF677 an inter-specific hybrid (Almond Peach) is propagated asexually as clone (8). It has been reported that rootstock GF677 is tolerant to salinity while rootstock nemagard (P. persica X P. davidiana) is sensitive to salinity (16). It has been reported that rootstock GF677 tolerated salinity (5.5 ds/m), (19) or 5.2 ds/m (17 and 14).However, as plant species and different cultivars within the same plant species vary considerably in their tolerance to salinity (10), properly selecting plants and/or cultivars that can be grown well under adverse conditions, created in the root zone by salinization, is the most efficient and environmentally friendly agricultural practice for a more permanent solution of the problem of salinity (10).
Despite the presence of information on the effect of salinity on concentration of nutrition elements of almond cultivars leaves and roots, tolerantscion/rootstock combinationshave not been introduced for this plant. Therefore, the aim of the present study is to evaluate the effects of salt stress on concentration of nutritional elements of selected almond genotypes leaves and roots, grafted on GF677 rootstock and introducing most tolerant genotypes to it.
Materials and Methods: In this research, the effects of salinity stress were investigated on nutrient of almond leaves and roots by a completely randomized design (CRD), with two factors, genotype (in the four levels) and irrigation water salinity (in the five levels) with tree replications in the research greenhouse of Seed and Plant Institute in the year 2013. Studied Genotypes included ‘Shokofeh’, ‘Sahand’ and ‘13-40’ budded on GF677 and ‘GF677’ (none budded as control) and irrigation water salinity included 0, 1.2, 2.4, 3.6 and 4.8 g/l of natural salt (whose electrical conductivity are equal to 0.5, 2.5, 4.9, 7.3 and 9.8 ds/m, respectively).Nutrition elements such as K+, Ca++, Mg++, P, Na+, Cl-, Zn++, Cu++, Fe++, Na+to K+ ratio, Na+ to Ca++ ratio, Na+ to Mg++ ratio, Na+ to P ratio, were investigated in selected almond genotypes leaves and roots. Then salinity stress was applied.
Results and Discussion:The results showed that type of scion and level of salinity had affected nutrient concentration of leaves and roots. Evaluation of nutrition elements concentration in leaves and roots showed that in the total studied genotypes, the highest percentage of Na+, Cl-, Na+to K+ ratio, Na+ to Ca++ ratio, Na+ to Mg++ ratio, Na+ to P ratio and the lowest percentage of Ca++, Mg++, P and concentration of Cu++ in leaves and roots and the lowest concentration of Zn++ in leaves were observed in treatment 9.8 ds/m. The result showed that the type of scion was effective in obstruction of Na+absorptionby therootsand their transportationtoleaves.Percentageof Na+, Cl-, Na+ to K+ ratio and Na+ to P ratio in levels of salinity 3.6 and 4.8 g/l and Na+ to Ca++ ratio, Na+ to Mg++ ratio in level of salinity 4.8 g/l in ‘Shokofeh’ cultivar were significantly lessthan other genotypes. Also, this cultivar could compare with control plants at levels of salinity 3.6 and 4.8 g/l by increasing the percentage of K+and concentration of Fe++ ,and it could tolerate the harmful effects of Na+ more than other genotypes.
Conclusion: Overall, the results showed that both rootstock and type of scion were effective in tolerance to salinity. GF677 rootstocks (non-budded) tolerated salinity of 2.4 g/l (4.9 ds/m), but withincreasingsalt concentration, plants were severely damaged. The results showed that the type of scion affected tolerance to salinity. In this research,at base concentration of nutritional elements,‘Shokofeh’ cultivar was the most tolerant cultivar against salinity stress. This cultivar could well tolerate salinity of 3.6 g/l (7.3 ds/m) and partly salinity 4.8 g/l (9.8 ds/m). In contrast, Sahand cultivar was the most sensitive cultivar to salinity stress. These cultivar as GF677 rootstocks (non-budded as control) only could tolerate salinity of 2.4 g/l.
Fatemeh Salimi; Farid Shekari; Javad Hamzei
Abstract
Using plant growth regulators at the stresses environment can improve plant growth and crop production. Hence, in this research response of photosynthesis rate, chlorophyll, soluble sugar and flower dry weight of chamomile to methyl jasmonate under different salinity levels was studied. Values of 0 (control), ...
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Using plant growth regulators at the stresses environment can improve plant growth and crop production. Hence, in this research response of photosynthesis rate, chlorophyll, soluble sugar and flower dry weight of chamomile to methyl jasmonate under different salinity levels was studied. Values of 0 (control), 75, 150, 225 and 300μM methyl jasmonate (MeJA) with salinity levels of 2, 6, 10 and 14 dS/m was evaluated as a factorial experiment based on a randomized complete block design with three replications. The effect of MeJA and salinity was significant for photosynthesis rate, leaf temperature difference (T), relative water content (RWC), chlorophyll a, chlorophyll b, total chlorophyll, soluble sugar and flower dry weight. Also, MeJA × salinity interaction affected all traits except T. The highest value of photosynthetic rate (9.99 µmol CO2 m-2 s-1 ), chlorophyll a, b and total chlorophyll, in averaging 5.98, 41.18 and 45.10 mg g-1, respectively, and flower dry weight (3.73 g pot-1) were obtained at 75μM MeJA and 6 dS/m salinity. But, there was no significant difference between 75μM MeJA×6 dS/m and 75μM MeJA×2dS/m for RWC and flower dry weight traits. Maximum soluble sugar was achieved at 75μM MeJA×14 dS/m treatment. In general, using of MeJA increased RWC and decreased undesirable effects of salinity. With decreasing RWC photosynthetic rate, chlorophyll and flower dry weight decreased, but T increased.
Maryam Kamali; Mahmood Shoor; Yahya Selahvarzi; Morteza Goldani; Ali Tehranifar
Abstract
To evaluate the effects of various concentration of carbon dioxide and salinity stress on morphophysiological characteristics of Amaranthus tricolor L. an experiment was conducted in greenhouse conditions in Faculity of Agriculture Ferdowsi University of Mashhad. the experiment was split plot based on ...
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To evaluate the effects of various concentration of carbon dioxide and salinity stress on morphophysiological characteristics of Amaranthus tricolor L. an experiment was conducted in greenhouse conditions in Faculity of Agriculture Ferdowsi University of Mashhad. the experiment was split plot based on completely randomized design with three levels of CO2 (380, 700, 1050 µl/L) and three concentrations of sodium chloride (0,150, 300 mM) with 3 replications. The results showed that in control carbone dioxide (380 µl/L), application of salinity to 300 mM, reduced shoot dry weight, plant height and leaf area from 9.34, 53.83 and 1001 to 3.71, 35.3 and 158 respectively. Interaction effects of salinity and carbon dioxide showed that in control salinity and 1050 µl/L carbon dioxide, shoot dry weight and plant height increased 46 and 38% respectively. in level of 150 mM sodium chloride, with increasing concentrations of carbon dioxide from 380 to 700 µl/L, leaf area increased from 134 to 358 cm2. at this salinity level, in concentration of 1050 µl/L carbon dioxide, leaf area was 287 cm2. The final results showed that increasing concentrations of carbon dioxide improves adverse effects of salinity. in characteristics such as leaf area and electrolyte leakage, carbon dioxide in 700 µl/L and in characteristics such as root dry weight, shoot dry weight and plant height concentrations of 1050 µl/L carbon dioxide showed a better reaction to salinity.
