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
Vali Rabiei; Sogra Heydari; Asghar Soleimani; Fahime Nasr
Abstract
Introduction
The Persian walnut (Juglans regia L.) is a valuable commercial crop with high economic and nutritional value. Nutrition management is one of the most important factors affecting the growth and performance of modern walnut orchards. The demand for high-quality walnuts is increasing day by ...
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Introduction
The Persian walnut (Juglans regia L.) is a valuable commercial crop with high economic and nutritional value. Nutrition management is one of the most important factors affecting the growth and performance of modern walnut orchards. The demand for high-quality walnuts is increasing day by day in the national and international markets. Horticultural production has undergone tremendous changes in recent years due to the development of innovative technologies, including nutrient management practices. Nutrient management of walnuts is one of the important factors for increasing yield and improving the quality of walnut kernels. The use of nitrogen, phosphorus and potassium fertilizers is essential for tree growth and the production of fruits such as walnuts. The enhancement in the use of fertilizers in an irrational manner has led to a decrease in soil productivity and multiple nutrient deficiencies. Minimizing the use of chemical fertilizers in fruit cultivation is the goal of integrated fruit production. The gravity of environmental degradation caused by the faulty cultivation practices has led to focus on ecologically sound, viable and sustainable farming systemsIn this study, in order to investigate the efficiency and feasibility of replacing sulfate-containing fertilizers with thiosulfate-based fertilizers, the effect of calcium thiosulfate and potassium thiosulfate fertilizers on increasing the yield and quality of walnut fruit was evaluated in an experiment.
Materials and Methods
This experiment was conducted in 1402, in a randomized complete block design with three replications and 5 trees per experimental unit in an orchard with 6-year-old Chandler trees grown from tissue culture seedlings in the Khoramdareh Agro-Industrial Complex. The experimental treatments included T1: regular orchard nutrition (control) including 50 kg/ha potassium nitrate calcium + 200 kg/ha potassium sulfate, T2: 100 L/ha calcium thiosulfate plus 200 kg/ha potassium sulfate, T3: 50 kg/ha potassium nitrate and calcium plus 100 L/ha potassium thiosulfate plus 125 kg potassium sulfate, T4: 100 L/ha calcium thiosulfate plus 100 L/ha potassium thiosulfate plus 125 kg potassium sulfate. After applying the treatments, after observing signs of ripening, the fruits of the tree were harvested and transferred to the laboratory for evaluation of biochemical and physical traits.
Results and Discussion
Analysis of variance for fruit and yield traits showed significant differences at the 1 and 5 % levels. Comparison of the means of these traits showed that the highest fruit dry weight, fresh and dry kernel weights, and kernel percentage were obtained in the calcium and potassium thiosulfate treatment, and the highest tree yield and yield efficiency per trunk cross-section were obtained in the calcium thiosulfate treatment. Calcium increases the growth of hairy roots, root cell division, root length and also enhance the absorption and transfer of nutrients and water to the plant, This led to an improvement in fresh and dry weight of the plant and yield. Calcium also increases the fresh and dry weight of the plant by increasing the transfer of carbohydrates from leaves to fruit. On the other side, potassium increases fresh and dry weight and yield by enhancing photosynthesis, carbohydrate formation and transport, maintaining intracellular pH, and absorbing nutrients from the soil. In addition, the results of the comparison of means showed that all treatments used increased the total phenol and flavonoid content of walnut fruit compared to the control, so that the highest total phenol and flavonoid content were obtained in the potassium thiosulfate and potassium and calcium thiosulfate treatments. Calcium reduces oxidative stress in the membrane through membrane strength and delays the degradation and reduction of phenolic compounds by strengthening the membrane and cell wall. Moreover, Potassium increases plant growth and photosynthetic activity, increasing the allocation of additional carbon to the shikimic acid pathway, thereby increasing phenolic substances such as phenols and total flavonoids. Potassium also increases phenolic compounds and antioxidants by increasing the activity of the enzyme phenylalanine ammonia lyase, which is a key enzyme in the synthesis of phenolic compounds. Analysis of variance of data related to crude fiber, total protein and crude fat of fruit showed significant difference between treatments at 1% level, but the effect of treatments on ash content of samples was not significant. Results of mean comparison showed that the highest amount of crude fiber was related to potassium and calcium thiosulfate treatment. Increased absorption and transport of nutrients is one of the important factors in increasing crude fiber in plants, and it seems that rapid absorption and transport of thiosulfate-containing compounds has led to improved fiber production. Analysis of variance of data related to linoleic and oleic acid traits of walnut fruit showed significant difference between treatments at 1% level and results of mean comparison also showed significant increase in linoleic acid content in fruits under calcium and potassium thiosulfate treatment and potassium thiosulfate treatment. There are two important sources for assimilation and oil formation. The first is the carbohydrate pathway that is produced in the leaf after photosynthesis and transferred to the fruit, and the second is the carbohydrate pathway that is formed during photosynthesis in the walnut fruit, which is converted into fatty acids after enzymatic processes. In this study, increasing sulfur, potassium, and calcium and increasing the absorption of trace elements due to thiosulfate consumption increased photosynthetic activity and increased the production of plant metabolites, which increased the fatty acids in walnuts. Therefore, the obtained results indicate high efficiency of calcium and potassium thiosulfate fertilizers in increasing quality and yield of walnut fruit.
Conclusions
Our findings indicated that calcium thiosulfate - potassium thiosulfate combination were the best treatments for increasing quantitative and qualitative characteristics of walnut fruit. These findings demonstrate the potential of calcium and potassium thiosulfate fertilizers to enhance walnut orchard productivity and fruit quality, making them a recommended choice for nutrient management strategies.
Keywords: Fatty acids, Nutrition, Biochemical traits of fruit, Yield efficiency
Niaz Gholi Firozbakht; Mehdi Rezaei
Abstract
Introduction: Size of fruit in Japanese plum has an important role in marketability and fruit quality. In Golestan province, one of the most important areas of plum production in Iran, due to high temperatures in summer that led to unfavorable conditions in fruit ripening stage, final fruit size are ...
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Introduction: Size of fruit in Japanese plum has an important role in marketability and fruit quality. In Golestan province, one of the most important areas of plum production in Iran, due to high temperatures in summer that led to unfavorable conditions in fruit ripening stage, final fruit size are reduced in commercial scale. In this respect, the large financial loss is imposed to plum growers. Today, synthetic auxins are widely applied in the commercial gardens of the world in order to increasing fruit size and improving fruit growth . Auxins can promotes cell division, cell enlargement in fruit growth stages and it also acts as sink for nutrients absorption. In this study, the effects of the foliar application of two synthetic auxins were investigated on fruit qualitative and quantitative of Japanese plums in Golestan province climatic conditions.
Material and Methods: A split-plot factorial experiment based on randomized complete block design with four replications was conducted in a commercial orchard from Run Agri Company in Golestan province, Iran for two years (2015 and 2016). The main factor was considered four plum cultivars including ‘Ghatreh Tala’, ‘Shablon Zodras’, ‘Shablon Mianras’ and ‘Shablon Dirras’ which were spraying by two synthetic auxins: NAA (0, 300 and 400 mg/l) and 2, 4-D (0, 10 and 30 mg/l) along and in combination. Fruit length, diameter, length to diameter ratio and fruit weight, yield, yield efficiency and percentage of first and second fruit grade production characteristics were evaluated. Data analysis was performed by SAS 9.1 software and the comparison of mean values was done by Duncan's multiple range tests at 0.05 of probability level.
Results and Discussion: The results showed that foliar application of auxin significantly increased fruit size and weight. The results showed that the response of plum cultivars to synthetic auxins was different. Fruit length and width of ‘Shablon Dirras’ cultivar were increased with the 2,4-D application at 10 and 30 mg/l , but in the ‘Shablon Mianras’ cultivar, the combination of 2,4-D with NAA improved fruit size. NAA at its highest concentration (400 mg/l) plus 2, 4-D at its highest concentration (30 mg/l) produced the largest fruits and the highest yield in ‘Shablon Mianras’ cultivar. Stern et al. (16) also obtained similar results from NAA and 2, 4-D treatments in plum, which is confirmed our results. The yield (kg/tree) and yield efficiency in plum cultivars increased significantly by synthetic auxin treatments. The average of yield (kg/tree) by 2, 4-D and NAA foliar application increased 30, 60, 28 and 34 percent in ‘Shablon Zodras’, ‘Shablon Mianras’, ‘Shablon Dirras’ and ‘GhatrehTala’ cultivars, respectively. The highest yield efficiency was obtained in ‘Shablon Mianras’ cultivar (0.38 kg/cm2) in 30 mg/L of 2, 4-D plus 400mg/L of NAA, which showed a 120 % increasing in comparison to control trees. Denis (7) reported increases the quantitative characteristics of stone fruits such as fruit size and weight by using synthetic auxin spray. The effect of auxin on increase cell proliferation and cell size are main reason for increasing the length and weight of the fruits (7). The results showed that 2, 4-D and NAA auxins were able to increase the percentage of first grade fruit relative in all plum cultivars in comparison to the control trees, but the concentrations and composition of plant growth regulators that increased the percentage of first grad fruits were not completely same to best treatments on fruit size, weight or yield. It referred to the first-grade fruits selection criteria. In selecting of best marketable fruits, in addition to the size of the fruit, others feature such as fruit appearance, color, physical damage and the absence of symptoms of diseases are also taken into grading. Temperature, water, nutritional and genetic conditions can affect the effect of plant growth regulator treatments (13).
Conclusions: Plum cultivars showed different reactions to synthetic auxin treatments. The largest fruit, highest yield and yield efficiency obtained in 2,4-D (30 mg/l ) with NAA (400 mg/l) in ‘Shablon Mianras’, ‘Shablon Dirras’ and ‘Ghatreh Tala’ cultivars and 2,4-D at 30 mg/l with NAA at 300 mg/l concentration in ‘Shablon Dirras’ and ‘Ghatreh Tala’ Cultivars. The highest degree of first grad-fruit was observed at 10 mg/l 2,4-D in ‘Shablon Zodras’ and ‘Dirrras’ cultivars and 300 mg/l of NAA in ‘Shabolon Mianras’ and ‘Ghatreh Tala’ cultivars.
