Pomology
afsaneh Salehi; Fatemeh Nekounam; Farhang Razavi
Abstract
Introduction
Apple (Malus domestica) belongs to the Rosacea family and is one of the most important fruit trees in temperate regions. Apple fruit is a rich source of vitamins, sugars, organic acids, minerals, fibers, and bioactive compounds and is widely cultivated due to its pleasant taste, aroma, and ...
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Introduction
Apple (Malus domestica) belongs to the Rosacea family and is one of the most important fruit trees in temperate regions. Apple fruit is a rich source of vitamins, sugars, organic acids, minerals, fibers, and bioactive compounds and is widely cultivated due to its pleasant taste, aroma, and texture. Due to the rising need for food and fiber per unit of land area, chemical fertilizers are becoming increasingly popular to increase yields from small plots of land. Chemical fertilizers pose major health risks and harm the environment when they are used in excess. Because of this, research in this area is heavily focused on finding and evaluating the efficiency of new products. One such approach is using biostimulants that can enhance the effectiveness of conventional mineral fertilizers. Plant biostimulants contain some nutrients (marine plant extracts, humic acids, amino acids and other natural products such as saponins and compost teas) that stimulate plant growth, even when administered in small amounts. Foliar application of seaweed extracts at 0.2% recorded maximum no. of fruits/tree, fruit weight, and yield/tree in valencia orange.
Materials and methods
In order to investigate the effect of biofertilizers on growth, yield and leaf nutrient contents of apple under climatic conditions of Zanjan, the experiment was carried out in a completely randomized block design with three replicates in 2023. Different concentration of seaweed (Alg; 0.075 and 0.15%), amino acid (GF Amino; 0.1 and 0.2%), humic acid (HA; 0.3%), commercial fertilizer Homarang, (Homa fert; 0.5%), combined chemical fertilizer (nitrogen, zinc and boron (Combinate fert; 1% urea, 0.3% zinc chelate and 0.1% boric acid)) and distilled water as a control were sprayed on the trees at 40 days after full bloom stage until runoff using a mechanical mist sprayer, and repeated three times with an 30 days interval until the physiological ripening of fruits. The experiment was carried out on 10-year-old Red Delicious apple trees grafted on M9 rootstocks. Shoot length, chlorophyll index, fruit drop percentage, yield efficiency, leaf area, leaf dry matter, leaf macro and micro nutrient were measured. The analysis of variance (ANOVA) and least significant difference test (P≤ 0.05) used to compare means within each sampling date. The Statistical analysis and standard error calculation were carried out using SAS software (V. 9.3).
Results and Discussion
The results showed that the foliar application of bio and chemical fertilizers significantly increased growth and fruit yield. So that, the highest increase in shoot length (39%) and leaf area (74.30%) compared to the control was obtained with application of seaweed 0.075%. Also, seaweed 0.15%, amino acid 0.2%, humic acid and amino acid 0.1% caused a significant increase in leaf area (42.02, 35.57, 22.27 and 16.20%, respectively) compared to the control. Foliar spray of seaweed, amino acid and chemical fertilizer increased chlorophyll index. The highest increase in chlorophyll index (50%) compared to the control was obtained with application of combined chemical fertilizer at 130 days after full bloom. These results are in agreement with the outcomes of other experiments conducted with seaweed on apple and on other crops such as grapevine. Therefore, this represents a further evidence of a possible role of seaweed extracts in the reduction of chlorophyll degradation and in delaying leaf senescence. The highest amount of nitrogen (1.66%), potassium (1.03%) zinc (150 mg g-1DW) and boron (82.5 mg g-1DW) and the lowest amount of phosphorus (0.44%) were obtained with application of combined chemical fertilizer. The highest value of iron was observed in leaf of trees treated with seaweed 0.15%, humic acid and commercial biofertilizer. Based on the results, it was observed that the amino acid, seaweed and combined chemical fertilizer have the greatest effect in reducing fruit drop (36.97, 33.37, 29.07%, respectively) compared to control) and increasing yield efficiency (respectively 2.75, 2.73 and 2.8 compared to control with 0.22 fruits No. cm-2 SCSA). These results partially are in agreement with another research performed on apple, where the use of a similar seaweed extract (Ascophyllum nodosum) was found able to induce a higher final yield. The hormonal components found in the extracts, particularly cytokinins, are assumed to be responsible for the increased yield in plants treated with seaweed. Previous studies mentioned that the application of biological fertilizers alone or in combination with the mineral fertilizers had positive influences on the leaf plate area, mean fruit weight and fruit chemical composition.
Conclusions
According to the results of this research, the use of biofertilizers, especially seaweed (0.15%) and amino acid (0.1%), are suitable and nature-friendly substitutes for chemical fertilizers and can play a significant role in increasing growth indices and yield of apples.
Pomology
Masud Fattahi; Abdolrahman Mohammadkhani
Abstract
Introduction
UCB-1 hybrid rootstock is propagated from the seed of a controlled cross between a P. atlantica female and a P. integerrima male. Clonal propagation of this rootstock is also necessary since it produces identical genotypes. UCB1 has recently been introduced in Iran. However, little ...
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Introduction
UCB-1 hybrid rootstock is propagated from the seed of a controlled cross between a P. atlantica female and a P. integerrima male. Clonal propagation of this rootstock is also necessary since it produces identical genotypes. UCB1 has recently been introduced in Iran. However, little research has been done on this subject. Water stress is one of the most important environmental stresses and occurs for several reasons, including low rainfall, high and low temperatures, salinity, and high intensity of light, among others. Drought stress is a multidimensional stress and causes changes in the physiological, morphological, biochemical, and molecular traits in plants. Proline is also found widely in plants and accumulates in large quantities in response to environmental stresses such as drought. It is the essential amino acids that accumulate in different tissues of the plant, especially in the leaves through the effect of water stress, and that the accumulation of it has a function in the regulation of osmosis in the cell as the proline is increased in the cytoplasm to counterbalance effort osmosis cell sap. Proline is an indicator of water stress tolerance and its increase in the leaf proof that the plant suffered drought stress, also is the way the plant tolerance to drought stress.
Materials and Methods
A pot experiment was conducted, to investigate the effectiveness of foliar applied proline in mitigating the concurrent effects of drought stresses on UCB1 rootstock, at greenhouse of Faculty of Agriculture, University of Shahrekord. Experiment was carried out in a completely randomized design with split arrangement having three replications. Chl. and carotenoid contents were determined according to Lichtenthaler (1987). Leaf discs were obtained from expanded leaves of each pot in the morning. The leaf discs were weighed immediately to obtain the fresh weight (FW), and submerged in distilled water for 4 h at 4◦C in dark condition and then weighed to prepare turgor weight (TW). The leaves were dried in a forced-air oven at 70◦C for 24 h, and the dry weight (DW) was recorded. The RWC of samples was calculated using the following equation (Bastam et al., 2012): RWC = [(FW–DW)/(TW–DW)] × 100
Levels of glycine betaine were quantified as described previously by Arakawa et al. (1990). To determine the free-proline concentration, leaves were homogenized in 5 ml of ethanol at 95%. Proline concentration was calculated with a standard curve and expressed as µg g−1fresh mass (Paquin and Lechasseur, 1979).
Results and Discussion
The UCB1 proximate analysis in the present study depicted that imposition of drought stress increased the leaf and root proline content and electrolyte leakage. Exogenous application of proline as foliar spray significantly increased the moisture content of leaf and root, RWC, Chl a and total chlorophyll. Exogenous proline application upregulated leaf and root proline contents and decreased the lipid peroxidation (decrease electrolyte leakage), resulting into improvement in chlorophyll contents. 150 mg. l-1 proline application gave maximum alleviation against stress.
Numerous reports depict that the exogenous application of proline as a foliar spray can play an important role in enhancing plant tolerance against drought stress, and our results are consistent with them. This ameliorating effect of exogenously applied proline can take the form of osmoprotection, cryoprotection, or protection against reactive oxygen species.For example, in various plant species growing under stress conditions, exogenously supplied proline provided osmoprotection and facilitated plant growth. Normally, proline accumulation in plants, is in response to drought or salinity stress occurs in the cytosol where it contributes substantially to the cytoplasmic osmotic adjustment. It actively takes part in plant osmotic adjustment under stressful environmental conditions. In addition to its role as an osmolyte for osmotic adjustment, it actively takes part to stabilize subcellular structures, biological membranes, proteins, and scavenge free radicals. It also plays a vital role in buffering cellular redox potential under stressful environmental conditions.
Conclusion
In summary, our results showed that, drought induces a decrease in moisture content, RWC, T Chl and carotenoids and an increase in some osmoregulators (proline, glycine betaine, TSC). The most favorable treatment was 150 mg.l-1 proline foliar spray. 150 mg.l-1 proline application gave maximum alleviation against stress. Foliar application increased the moisture content of leaf and root, as well as increased the Chl a, total, RWC and proline content of leaf and root. It can be suggested that the foliar application of proline (150 mg L-1) used as a plants defense factor against drought stress conditions.
Pomology
Salahodin Maslahati fard; Hamid Hassanpoor
Abstract
Introduction
Strawberries with the scientific name Fragaria × ananassa Dutch. It belongs to the Rosaceae family. Strawberry is one of the fruits that has found many fans around the world due to its aroma, taste and nutritional value. The main characteristics of strawberry fruit quality are ...
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Introduction
Strawberries with the scientific name Fragaria × ananassa Dutch. It belongs to the Rosaceae family. Strawberry is one of the fruits that has found many fans around the world due to its aroma, taste and nutritional value. The main characteristics of strawberry fruit quality are flavor (ratio of sugar to acid and volatile compounds) and color. Excellent plants need nitrogen in addition to carbon to meet their growth and food needs. The most vital compounds in plant living cells are proteins, which are made up of amino acid building blocks. Different amino acid sequences cause variation in the resulting proteins. Arginine is a multifunctional amino acid found in living cells and is an important storage and transport form for organic nitrogen in plants. In addition to its function as a major component of protein, it is an essential metabolite for many cellular and growth processes. Studies have shown that arginine increases the synthesis of flowering hormones related to flowering and fruiting. This amino acid is also involved in the activity of various plant enzymes. This amino acid binds to membrane nucleic acids and phospholipids and increases the activity of enzymes such as catalase. Due to the importance of producing organic products and also due to the fact that so far no study has been done on the effect of arginine on the growth and physiological characteristics of strawberry cultivar Albion. Therefore, in this study, the role of arginine on some quantitative and qualitative characteristics of albumin strawberry fruit in hydroponic conditions was investigated.
Materials and Methods
The present study was conducted in the greenhouse of the Faculty of Agriculture, Urmia University, Iran. In this study, the effect of arginine with three levels (0, 100 and 200 mg / l) on the quantitative and qualitative characteristics of Albion strawberry fruit under deficit fertigation conditions with two levels (140 and 180 ml) in a completely randomized design with 4 replications. In this study, traits such as fruit flavor, titratable acidity, soluble solids, fruit firmness, vitamin C, total phenol, total flavonoids, total anthocyanins and total antioxidant capacity were investigated. XTPlus-TA tissue analysis device was used to measure the firmness of fruit texture. Vitamin C content of fruit extract was measured by ascorbic acid based on dye reduction of 2,6 dichlorophenol indophenol (DCPIP). The Titration method was used to measure titratable acidity (TA). ATAGO manual refractometer was used to measure the amount of soluble solids. Also for measuring the taste of fruit by Voca et al. used. The Absorption difference method at different pHs was used to measure total anthocyanin. Total antioxidant capacity was assessed using the DPPH (1,1-diphenyl-2-picrylhydrazyl) method. Folin-ciocalteau method was used to measure the total phenol content. Shin et al. Method was used to measure the total flavonoid content of fruit.
Results and Discussion
The results obtained from the analysis of variance of the data showed that the measured indices were affected by different treatments of arginine and deficit fertigation. Based on the results, arginine treatment on fruit flavor, titratable acidity, soluble solids, fruit firmness, total anthocyanin, vitamin C, phenol, flavonoids and total antioxidant capacity showed a significant difference. The highest amount of soluble solids, fruit flavor and firmness of fruit texture were recorded in arginine treatment with a concentration of 100 mg / l under normal fertigation conditions (180 ml). Also, the highest amount of phenol and total flavonoids was observed at the same level of fertigation, albeit with arginine treatment at a concentration of 200 mg / l. Also, the highest amount of anthocyanin, vitamin C and total antioxidant capacity were recorded in arginine treatment with a concentration of 200 mg / l, in conditions of mild deficit fertigation (140 ml).
Conclusion
Excessive use of chemical fertilizers in agricultural production, especially in hydroponic cultivation in greenhouses, causes fertilizer wastage and as a result increases production costs as well as increases greenhouse drainage. Therefore, it has destructive effects on the environment, so reducing the amount of nutrient solution can be a management option to reduce the harmful effects on the environment and save water. Also, due to the importance of producing organic products and increasing demand, the use of healthy and organic compounds such as amino acids (arginine) to increase the quality and quality of the product, is very necessary. In the present study, arginine treatment increased the quality of strawberry fruit by affecting its photochemical content such as total antioxidant activity, vitamin C, total phenol, anthocyanin, etc. in low solubility conditions. Also, by increasing the firmness of the fruit texture, it improved the appearance quality of the fruit, which is important for attracting the consumer's attention. In general, the results showed that arginine spraying (200 mg / l) in normal solution and mild dissolution conditions can be effective in improving the quality of strawberries cultivated in hydroponic conditions.
Growing vegetables
Saeid Khosravi; Maryam Haghighi
Abstract
Introduction: Brassinosteroids promote plant growth by enhancing some metabolic activities such as photosynthesis, nucleic acid biosynthesis, proteins and carbohydrates. Mechanisms of resistance and tolerance in plants have been developed to tolerate water deficit stress. One way to deal with drought ...
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Introduction: Brassinosteroids promote plant growth by enhancing some metabolic activities such as photosynthesis, nucleic acid biosynthesis, proteins and carbohydrates. Mechanisms of resistance and tolerance in plants have been developed to tolerate water deficit stress. One way to deal with drought is to use plant growth regulators. Brassinosteroids were first extracted from the pollen of turnip (Brassica napus) and were considered as the sixth group of plant growth regulators. These compounds stimulate growth and cell division and affect electrical properties, membrane permeability, stability and activity of membrane enzymes. Nowadays, brassinosteroids have been extracted from various plants and their structure and function have been identified.Materials and Methods: This experiment was conducted in a factorial experiment based on a completely randomized design on Capsicum annuum L. Castello cultivar under the average daily temperature of 25 °C and 18 °C at 75% relative humidity in greenhouses. Research conducted by the College of Agriculture, Isfahan University of Technology, with four drought treatments using polyethylene glycol 6000 solutions at four levels of 0, -6, -7, and -8 bar. Brassinosteroids were sprayed in two 1 μM control levels. Pepper seeds planted in transplanting trays containing 1 to 2 volumes perlite and vermiculite substrate. When the actual leaf of seedlings appeared, the root thoroughly rinsed with distilled water and then were transferred to black plastic containers with a diameter of 16 and height 13cm and 1L volume containing Johnson's nutrient solution including four dry treatments using 6000 polyethylene glycol solution and aerated in control for 15 minutes every 5 minutes. At the end of the experiment, vegetative factors such as fresh and dry weight of different parts of the plant, plant length, and volume, and physiological factors such as proline and abscisic acid content and chlorophyll fluorescence changes were measured.Results: The results of the analysis of variance table showed that brassinosteroid had no significant effect on most vegetative traits except root volume and weight and all physiological traits except chlorophyll fluorescence and the mentioned traits increased with the application of 1 mM brassinosteroid. However, the main effects of drought except for amino acid and the interaction of drought and brassinosteroids were significant on all traits. The results of the main drought effects showed that the root fresh weight at -8 bar and dry weight at -7 bar significantly decreased, whereas fresh and dry weight of the shoots at lower than -6 bar. The onset of decline showed that the root length and volume appeared to decrease with the onset of stress by -6 bar and the plant length also reduced with the first stress level. Drought stress at -6 bar level decreased chlorophyll fluorescence, chlorophyll index and Abscisic acid while at -7 bar decreased protein and increased proline. The results also showed that the amount of sulfuric, essential and unnecessary amino acids were significantly reduced by drought stress and brassinosteroid had no effect. Total amino acid content decreased with drought stress but there was no significant difference with control. With increasing drought stress, the fresh and dry weights of shoots decreased and the intensity of shoots decreased. The intensity of shoot growth decreased with the use of brassinosteroids at moderate stress but the mentioned trait showed the same adverse effects at all levels of stress. Brasinosteroid application decreased stress indices such as proline (7%) and abscisic acid (50%) and this decrease was more pronounced in proline, especially in more severe treatments. Amino acid and protein levels decreased with drought stress, and the use of brassinosteroids could not be effectively affected by this reduction, especially for the compounds and the amount of amino acids.The results of biplot analysis showed that the vegetative and protein traits had better mean in stress condition in the presence and absence of stress and in higher stress severity and application of brassinosteroid affected root fresh weight and abscisic acid content more than the other traits. While in mild stress it seemed to be more effectively on the steroid and most of the vegetative and physiological traits than the control.Conclusion: It seems that the application of brassinosteroids on pepper seedling in drought stress at a concentration of 1 μM is effective in maintaining vegetative properties and reducing negative effects of stress and reducing stress indices.
َAysan Samadi; Akbar Hassani; Majid Gholamhoseini
Abstract
Introduction: Plant growth promoting bacteria are beneficial microorganisms that produce plant resistance to a variety of biological and non-biological stresses, including drought, extreme temperatures, salinity, toxic metals, etc, and increase plant productivity and yield. The use of these microorganisms ...
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Introduction: Plant growth promoting bacteria are beneficial microorganisms that produce plant resistance to a variety of biological and non-biological stresses, including drought, extreme temperatures, salinity, toxic metals, etc, and increase plant productivity and yield. The use of these microorganisms as biological agents in increasing soil fertility and improving agricultural productivity has been studied by many researchers, so a proper understanding of their effect on drought resistance can be effective in water resources management. Useful in field and reducing environmental effects of using chemical fertilizers. The purpose of this study was to investigate the effect of some bio-fertilizers on growth and some physiological and biochemical characteristics of red radish and in comparison with potassium sulfate application under drought stress.
Material and Methods: In other to investigate the effect of application of bio-fertilizers containing potassium-soluble bacteria (Pseudomonas koreensis and Pseudomonas vancouverensis), phosphorus-solubilizing bacteria (Pseudomonas putida) and nitrogen-fixing bacteria (Pantoea agglomerans) on plant growth and function, this experiment was done with 10 treatments and three replications in the form of completely randomized design in greenhouse. Finally the statistical population consisted of 30 pots of 10 treatments and three replications for red radish. Drought stress was applied in such a way that the apparent symptoms of stress were seen in the plants and the amount of water used was the same for all plants. The experiment was carried out in greenhouses and nylon pots with a capacity of 6.5 kg were used. The soil was prepared using a calcareous soil of Zanjan University research field. Its absorption was less than critical. Organic matter content was 0.4% and lime equivalent was 14.1% pH of soil 7.57 and EC of abstract soil paste was 2.21. Pots were treated with municipal water for 25 days after planting. EC values of water was 400 µS / cm that irrigated the plants every three days. The desired bio-fertilizers were added to the pots with irrigation water. After 25 days, 15 pots of treatments 4 to 6 were subjected to drought stress. 40 days after planting before drying of the plants, weight, moisture content of plant tissue, leaf proline content, total free amino acid, and total soluble sugars in leaf extract were measured. Analysis of variance was performed using SAS software and LSD test at the 5% level was used to compare the means.
Results and Discussion: Results of analysis of variance showed that the effect of different treatments on aerial fresh weight was significant at 1% level. Fertilizer treatments under stress and non-stress conditions significantly increased aerial fresh weight. Among non-stress treatments, the highest fresh weight was obtained from treatment 2 (10.03 g / pot) and the lowest was in control treatment (6.55 g / pot). Among the drought stress treatments with application of different fertilizers used, treatment 8 (9.19 g / pot) had the highest and treatment 6 (7.04 g / pot) had the lowest fresh weight. Application of potassium sulfate fertilizer increased the fresh weight of aerial part both under stress and non-stress condition. Potassium soluble bio-fertilizer alone and in combination with other bio-fertilizers increased radish aerial fresh weight, which was not significantly different from potassium sulfate fertilizer. In radish, drought stress affected the tuber fresh weight more. The radish plant uses the water of the tuber reserve in drought stress so that the leaves are less susceptible to stress. In non-stress conditions, application of potassium sulfate fertilizer and bio-fertilizers in radish increased yield. Potassium sulfate effect was greater. In stress conditions, the effect of bio-fertilizers was more than potassium sulfate in stress condition. The effect of potassium soluble bio-fertilizer application was almost identical with the combined application of different biofertilizers. Drought stress increased the concentration of proline, amino acids and soluble sugars in leaves and tubers of radish. Increasing concentration of these compounds indicated that plants were resistant to drought. Application of potassium sulfate and bio-fertilizers decreased these concentration and the effect of bio-fertilizers was more than that of potassium sulfate. The amount of ion leakage also increased under drought stress but leakage decreased by using potassium sulfate and bio-fertilizers. Drought stress also reduced the starch concentration in leaves and tubers of radish, which is a consequence of drought stress.
Conclusion: In general, application of potassium sulfate and bio-fertilizers moderated the effects of drought stress and in some cases the effect of biofertilizers was greater. Integrated use of bio-fertilizers was not significantly different from the use of potassium soluble bio-fertilizer alone. So, the results of this study showed that the use of bio-fertilizers can be included in the plant nutrition program as a factor in reducing the negative effects of stress on plants.
