Plant Nutrition, Soil Fertility and Fertilizers
Ali Reza Jafarnejadi; Farhad Moshiri; Fatemeh Meskini-Vishkaee
Abstract
Introduction: Arid and semi-arid areas such as Khuzestan province has highly fragile ecosystems that are characterized by low soil fertility, and high organic matter decomposition rates. Moreover, according to the FAO, around 12% of world soils and 65% of Iran's soils are calcareous and more than 20 ...
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Introduction: Arid and semi-arid areas such as Khuzestan province has highly fragile ecosystems that are characterized by low soil fertility, and high organic matter decomposition rates. Moreover, according to the FAO, around 12% of world soils and 65% of Iran's soils are calcareous and more than 20 % of the irrigated farms in the world is affected by salinity. Since soil carbon saturation is low in saline-calcareous soils, the use of organic manure can be effective in increasing soil organic carbon and supplying essential nutrients in crop production. Applying organic manure in agriculture has been considered during the last two decades due to its high-quality products, high price, and low market availability of synthetic fertilizers, chiefly in developing countries. The manure application, both alone or in combination with inorganic fertilizers, is effective in increasing soil organic carbon (SOC) content and improve in soil fertility, microbial activity, and soil water retention capacity. Now the integrated application of organic and chemical fertilizers is inevitable for sustainable production and soil conservation. Hence, comprehension of the response of the soil and crop to applying organic and inorganic fertilizer may help to determine proper manure management strategies to enhance SOC and improve soil health and its ecosystem services. Thus, the aim of the study was to investigate the effects of different fertilizer managements on nutrient content of soil and wheat in saline-calcareous soils of Khuzestan province.Materials and Methods: To evaluate the effect of the integrated and long-term application of chemical and organic fertilizers on the nutrient content of soil and wheat grain in fixed plots, this research was carried out in Khuzestan province (Ahvaz city) in a calcareous- saline soil with silty clay texture under wheat cultivation (Barat cultivar) as a randomized complete block design in six treatments with three replications for four years (2017-2021). The treatments included T1: unfertilized control, T2: application of nitrogenous, phosphorus and potassium chemical fertilizers based on soil test, T3: application of 20 tons of cattle manure every two years + 75% of recommended nitrogen + 50% of the recommended phosphorus and potassium, T4: application 20 tons of bagasse every two years + 75% of the recommended nitrogen + 50% of the recommended phosphorus and potassium, T5: annual application of 20 tons of cattle manure + 75% of the recommended nitrogen, T6: annual application of 20 tons of bagasse + 75% of the recommended nitrogen. In treatment T2 recommended dose of P2O5, K2O, and 30 % of recommended N were applied at the time of second irrigation; the remaining N dose was applied in two splits at tillering (40 % of recommended N) and booting stages (30 % of recommended N). The organic manures were incorporated in the soil (depth 0-15 cm) a week before sowing. At the end of the growing season, wheat yield components were measured. At the end of the growth season, some soil properties involved pH, salinity and SOC, and the concentration of nitrogen, phosphorous and potassium in soil and grain wheat were determined. SAS v.9.1 statistical software and LSD test were used to compare the means of the studied treatments.Results and Discussion: The mean values of SOC varied in range of 0.60 to 0.73 %. As a result of applying treatment T2 (inorganic fertilizers application as alone), no significant difference was observed in SOC compared to the control treatment (p< 0.05). Compared to unfertilized control treatment, the SOC content were increased significantly by the use of cattle manure at T3 treatment (0.13 %), which could be attributed to the larger proportion of tenacious organic compounds in organic fertilizers than in chemical fertilizer. The highest concentration of soil available phosphorus (19.8 mg kg-1) was obtained in the integrated application of chemical fertilizer and cattle manure (T3), which is 60 and 169 % higher than those in the exclusive chemical fertilizer application (12.35 mg kg-1) and control (7.35 mg kg-1) treatments, respectively. The highest average soil available potassium concentration (253.3 mg kg-1) was also observed in T3. The results showed that the application of different fertilizer treatments was significant only on the nitrogen concentration of wheat grain (p< 0.01). The increase in wheat grain nitrogen concentration due to the application of integrated fertilizer treatments (28-38% increase compared to the control treatment) was significantly higher than the chemical fertilizers treatment (19% increase compared to the control treatment).Conclusion: Based on the results of this research, it was found that the integrated application of organic and inorganic fertilizers has a more positive effect on improving soil fertility in the long term than using them alone. Moreover, the results indicated that the use of cattle manure was more effective than bagasse manure which may be due to its lower carbon to nitrogen ratio (21.3). The integrated use of organic and inorganic fertilizers not only improve soil fertility, but also increases the efficiency of chemical fertilizer use, which reduces the basic chemical fertilizers consumption. Therefore, it is recommended to application of 20 tons of cattle manure every two years + 75% of recommended nitrogen + 50% of the recommended phosphorus and potassium (T3) in the saline-calcareous soils under wheat cultivation in arid and semi-arid climates such as southern of Khuzestan province.
Plant Nutrition, Soil Fertility and Fertilizers
Fatemeh Meskini-Vishkaee; Ali Reza JAfarnejadi
Abstract
Introduction: In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, dust storms ...
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Introduction: In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, dust storms in arid and semi-arid climates are one of the most important environmental and pollution problems, as they directly and indirectly reduced the quality and quantity of agricultural products. Dust occurrence frequency in the country, especially in the western and southwestern regions increased in the last decades. Hence, increased dust occurrence frequency and intensity during the growth period of agricultural crops is one of the most substantial risks in agricultural sustainable production in Khuzestan province. Thus, the aim of the study was to investigate the effects of dust occurrence and farm management practices applied to reduce the effects of this stress on wheat yield indices as a strategic agricultural product in Khuzestan province. Materials and Methods: This study was carried out in Khuzestan province in a calcareous and saline soil with clay loam texture under wheat cultivation (Barat cultivar) as a split plat experiment in a randomized complete blocks design with three replications. Two agricultural farm managements included 1) the custom of the farmer (traditional farming) and 2) nutrition management (soil test, soil balanced and complementary nutrition) based on plant phenological growth stages. In each farm management operation, four leaf washing treatments including 1) without leaf washing, 2) leaf washing after the occurrence of dust phenomenon in the tillering stage, 3) leaf washing after the occurrence of dust phenomenon in the booting stage and 4) leaf washing after the occurrence of dust phenomenon in both the tillering and booting stages, in plots with an area of 20 m2 were applied in three replicates. At the end of the growth season, wheat yield indices involved thousand kernel weight, number of grains per spike, biomass weight, grain yield and the number of tillers per square meter in different treatments were determined. SAS v.9.1 statistical software and Duncan's multiple range test were used to compare the means of the studied treatments.Results and Discussion: The results showed that the highest wheat grain yield was observed in the treatment of balanced nutrition management and leaf washing after dust occurrence at two wheat growth stages (5180 kg ha-1), while the least wheat grain yield was in the traditional management and no leaf washing treatment (2830 kg ha-1). The interactions of farm management practices and different leaf washing treatments on biomass, grain yield, harvest index, thousand kernel weight and number of tillers per square meter were significant (p< 0.01). In the traditional management of the farmer, using the plant leaves washing at only one wheat growth stage after the occurrence of dust caused about 30% increase in wheat grain yield on average (24 and 35% increase in grain yield as a result of leaf washing after dust, respectively, in the tillering and booting stages). While in the traditional management and leaf washing at both two stages of wheat growth, it increased the wheat grain yield by 43%. In addition, the results showed that by using balanced nutrition management without leaf washing, wheat grain yield and harvest index increased by 10 and 9%, respectively. Application of balanced nutrition and leaf washing after the dust occurrence at both two wheat growth stages (tillering and booting) caused 32, 59, 21 and 11% increase in biomass, grain yield, harvest index and thousand kernel weight of wheat.Conclusion: Based on the results of this research, it was found that the use of different management operations in the farms, such as balanced nutrition of the crop based on the plant growth phenological stages and the leaves washing after the occurrence of dust, can significantly reduce the damage of wheat yield caused by the occurrence of dust. However, it should be noted that despite the positive and significant effect of washing the plant leaf surface after the occurrence of dust phenomenon on reducing wheat yield damage, the time of leaves washing application is very important. Because if immediately after washing the leaf surface of the plant, the dust phenomenon occurs again, the wetness of the plant leaf surface causes more dust particles to deposit on it and the damage caused by dust on wheat yield indices increases.All right reserved.
Ali Reza JAfarnejadi; Fatemeh Meskini-Vishkaee; Mohammad Hadi Mousavi Fazl; Gh. Lotfali Ayeneh; Leila Behbahani
Abstract
abstractIntroduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, being ...
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abstractIntroduction In Iran, salinity is a pervasive and limiting Factor of agricultural sustainable production. Plants in saline conditions are exposed to limited absorption of nutrients, water and toxicity of some elements and subsequently, their yield will be affected by salinity. Moreover, being calcareous, the salinity of soil and irrigation water, low organic matter in the country's arable soils, and excessive consumption of phosphate fertilizers cause a lack of available nutrients for the plant uptake. As regards more than three billion people in the world suffer from a lack of micro nutrients, the bio-enrichment in strategic products such as wheat is necessary.Materials and Methods This study was carried out in Khuzestan province in a calcareous and saline soil with silty clay texture under wheat cultivation as a factorial experiment in a randomized complete blocks design with three replications. Factors included four levels of zinc (zero, 30, 60 and 120 kilograms per hectare of zinc sulfate) and the four levels of iron (zero, 2.5, 5, 7.5 kilograms per hectare of Fe- EDDHA). Zinc fertilizer treatments were used as application in soil and simultaneously with basic fertilizers (phosphorus and potassium fertilizers). While, iron fertilizer treatments were applied as irrigation fertilizer during wheat tillering stage. At the end of the growth season, wheat yield components (1000-seed weight, number of grains per spike, biomass weight, grain yield, number of tillers per square meter) and quality characteristics including hectoliters, seedling number, protein percentage, grain hardness and moisture content in different treatments were determined. MSTAT-C statistical software and Duncan's multiple range test were used to compare the means of the studied treatments.Results and Discussion The results showed that the interactions of zinc and iron on 1000-grain weight, number of grains per panicle and number of tillers and simple effects of zinc on total yield were significant (p< 0.01). The highest wheat grain yield was obtained in the treatment of 120 kilograms per hectare of Zn and 2.5 kilograms per hectare of iron and was equal to 6723 kilograms per hectare. The results showed that increasing one element alone had a negative effect on the number of plants per square meter. So that the lowest number of tillers per square meter (489 tillers per square meter) was observed when 60 kilograms per hectare of zinc fertilizer was consumed without iron fertilizer application. In other words, the imbalance in the amount of nutrients caused a significant reduction in the number of plants per square meter. Although the role of iron in yield and yield components of wheat in saline conditions was less than the element zinc, but the combined use of zinc and iron in a certain ratio had a positive effect on the yield components of wheat. Despite the less effect of iron application than zinc on wheat yield and yield components in saline conditions, the combined application of zinc and iron in a certain ratio had a positive effect on the wheat yield components. Combined and separate application of iron and zinc had no significant effect on wheat grain quality indicators including hectoliters, hardness and moisture. While the application of the most value of zinc caused a significant decrease in the wheat grain zeleny index. Higher levels of zinc fertilizer reduced the zeleny number of wheat grain, but the results showed that iron fertilizer levels followed the opposite trend rather than the element zinc. The least protein content (12.8%) was obtained in the treatment of 120 kg zinc fertilizer per hectare, which showed a statistically significant difference with the control treatment. Based on economic analysis, the application of 30 kg of zinc fertilizer per hectare, 2.5 kg of iron fertilizer per hectare and the combined application of both zinc and iron fertilizers resulted in a benefit-to-cost ratio of 2.3, 3.1 and 2, respectively.Conclusion Based on the economic analysis of treatments, their effect on qualitative and quantitative yield of wheat and the role of these micronutrients in human health, application of 30 kg ha-1 Zn fertilizer (as application in soil) and 2.5 kg ha-1 Fe fertilizer (as Irrigation fertilizer) in the wheat tillering stage was suggested in saline soil and climate conditions of khuzestan province.All right reserved. All right reserved. All right reserved.
