The advent of nanotechnology has led to new achievements in the different fields of science and technology. The minified size of materials under this technology discloses certain novel or hitherto ignored features and properties of these materials. It is true that nanotechnology has helped enhance certain features of fertilizers as evidenced by a number of studies reporting their positive effects on different plants. However, it should be noted that most of these studies were performed under laboratory conditions and considered only short periods of plant life, in many cases only up to germination. This is while there are many reports showing the adverse consequences of using nano-materials. For example, nanoparticles of aluminum, iron, zinc, titanium, nickel, and silver or hydroxyapatite nanoparticles and carbon nanotubes have caused reduced growth in onions, vetch, rye, rice, beans, corn, cucumber, sorghum, and tomato plants. These inconsistent reports call for exhaustive investigations to determine the interactions between nano-materials and plants and their final fate in the plant and food chain before they can be used as fertilizers. Since plants stand at the beginning of the food chain, introduction and accumulation of nano-materials inside them might help transfer these materials to higher levels of the chain to end up in the human body. This paper studies the effects of high concentrations of nano-materials on plant growth in certain species, the associated damages, and the uptake and accumulation of nanoparticles in plant.

To investigate the response of corn to combined application of chemical fertilizers with rhizobacteria plant growth promoting, an experiment was conducted in 2017 at Research farm of Agricultural and Natural Resources Campus of Tehran University, Karaj, Iran, in a randomized complete block design with four replications. Four nutritional treatments including T1 (Control treatment without applying fertilizer), T2 (Just PGPRs), T3 (Use chemical fertilizers based on soil test) and T4 (T3 + PGPRs) were considered. According to the results, the highest total dry weight (3.9 kg/m2), crop growth rate (79.8 g.m-2.day-1), net assimilation rate (15.3 g.m-2.day-1) and grain yield (18.2 ton.ha-1) were observed in T4 treatment and T2 treatment produced the highest  leaf area index (5.3), leaf area duration (205.2) and specific leaf weight (78.5 g.m-2) . Also, the lowest value of all traits was observed in in T1 (control) treatment. The results showed that the presence of rhizobacteria plant growth promotioninduction in the corn nutrition program increased the growth and growth indices of the plant. Combined application of chemical fertilizers with rhizobacteria plant growth promoting resulted in the highest growth and final grain yield of corn.

In congruence with the idea of sustainable development, integrated soil fertility and plant nutrition management has received global attention. The challenges facing soil fertility and plant nutrition in Iran include low soil organic carbon and nutrient contents, imbalanced plant nutrition, low nutrient efficiency, ineffective soil fertility system, environmental stresses, non-efficient fertilizer application, and inadequate knowledge transfer to users. Under these conditions, recommending proper fertilizers will be a multi-faceted and complex task. The development of a framework that incorporates all the factors involved into a single management package is the prerequisite to the integrated soil fertility and plant nutrition management as a smart system for applying an optimal assortment of chemical, organic, and biological sources of nutrients well adapted to environmental and local conditions and aimed at optimized exploitation of inherent soil capacities in a cropping system while sparing negative effects on soil ecological services. The desired integrated management system must be capable of duly accounting for all the components including plant variety; chemical, organic, and biological fertilizers; cropping system; climatic and soil conditions; and socio-economic parameters. The present study introduces the following three steps to achieve an integrated management system: 1) participation of all the stakeholders in the design, prioritization, implementation, and monitoring processes; 2) integrated use of chemical, organic, and bio-fertilizers in terms of amounts, timing, and method of application well adapted to the nutritional requirements of the plant varieties grown in the established cropping system with due consideration of environmental stresses; and 3) dissemination of localized knowledge and know-how of the integrated management system with the help of local extensionists and volunteer farmers from a pilot farm for replication and achievement of the expected outcomes in other farming sites.

To evaluate the relationships between soil inorganic phosphorus P (Pi) fractions, the soil P test and plant parameters such as plant P uptake, dry matter yield, tissue P concentration and relative yield, glasshouse experiments and chemical analyses were conducted on 13 calcareous soils from six agricultural and seven adjacent bushland (virgin soil) sites. Four rates of P (0, 15, 30, 60 mg/kg soil) were applied as reagent-grade KH2PO4 to the soils in a randomised complete block design with three replications. Perennial ryegrass (Lolium perenne cv. Roper) was grown and forage was harvested five times over a period of 210 days. Successive harvesting resulted in the depletion of plant available P as measured by NaHCO3-extractable P, which coincided with the decrease in the plant dry matter yield and P uptake. After five harvests, the order of reduction in Pi fractions induced by cropping without added P was Ca10-P>Al-P>Ca2-P>Ca8-P>occluded-P>Fe-P for the virgin soils and Ca2-P>Al-P>Ca10-P>Ca8-P>Fe-P>occluded-P for the agricultural soils. The order of abundance of Pi fractions for P treated-soils was non-occluded Al and Fe phosphate (Al-P+Fe-P)>secondary Ca-bound P (Ca2-P+Ca8-P)>acid-extractable P (Ca10- P)>occluded-P for both virgin and agricultural soils. Although a marked proportion of added P was transformed into less soluble Al and Fe phosphates, successive harvesting had depleted considerable percentages of these fractions. Highly significant (p<0.001) relationships were found for P uptake vs. Olsen-P, P uptake vs. Pi fractions (Ca2-P, Ca10-P, Al-P, Ca8-P, Fe-P) and Olsen-P vs. Pi fractions. NaHCO3-extractable P seems to be adequate for evaluating plant available P in calcareous soils. However, the closer relationship for the Fe-P fraction vs plant P uptake than for Olsen-P versus plant P uptake indicates that NaHCO3 may not provide the best estimate of plant available P for calcareous soils. Using stepwise regression analysis, it was found that the Ca2-P fraction was most predictive of P uptake (60%), total dry matter (68%), relative yield (74%) and Olsen-P (69%), followed by the Fe-P fraction.

Phytoremediation of lead using plants in lead-contaminated soils is a new and safe environmental technology. By adding chelators and increasing plant extraction, the efficiency of this technology can be increased. In this regard, we evaluated the effect of adding EDTA chelates to lead-contaminated soils to investigate the amount of lead accumulation in a medicinal plant, Calendula officinalis. We designed a factorial experiment in the form of a completely randomized, with three replicates in pots and two factors including EDTA at two levels (0, 50 mg kg-1) and lead at four levels (0, 30, 90, and 270 mg kg-1). In this plant, the accumulation of lead was accompanied by an increase in the amount of lead in the soil due to the addition of EDTA to the soil. The results showed that EDTA significantly increased the lead translocation of lead from roots to the aerial part of the plant.Total Chl. and shoot dry weight decrease significantly in EDTA treatment than control specific at a high level of Pb in the soil. Also, the results showed that EDTA increased lead removal from soil to soil solution and increased lead translocation from roots to the aerial part of the plant of Calendula officinalis. In general, the results of this research showed that with the careful management and EDTA use in lead extraction, it has provided a cost-effective and safe environmentally strategy.

Development of saffron corm resources with higher ability to acquire nutrients and produce more dry matter may offer one solution to mitigate the yield loss problem in growing areas. In the present study, variability in growth, nutrition, and biomass production among saffron ecotypes grown for a two-year field experiment was investigated at Kerman, a semi-arid region of Iran, during the 2015-2016 and 2016-2017 growing seasons. The results indicated that the studied ecotypes significantly differed in the mentioned parameters and responded differently to growing seasons. High-agronomic performance (yield) and nutrient-efficient ecotypes, e.g. Ferdows, Sarayan, and Bajestan, accumulated more nutrients as a result of increased Relative Growth Rate (RGR) and Net Assimilation Rate (NAR) before the critical stage, resulting in higher dry matter production. In contrast, ecotypes with lower potential to acquire nutrients, e.g. Zarand and Torbat, had lower growth and dry matter. Further, the results showed that variation in nitrogen (N) concentration in corms and leaves was not significant, although significant variation existed in N uptake, N uptake efficiency, and N use efficiency. This can be due to variation observed in the ability of corms to utilize nutrients for dry matter production. Cluster analysis revealed the presence of highly efficient, moderately efficient, and inefficient ecotypes. Generally, the results indicated that ecotypes with higher growth rate before critical stage showed more potential to uptake and utilize nutrients to produce more dry matter, and exhibited more nutrients use efficiencies. Overall, this study suggested that the nutrient acquisition capacity of ecotypes, a desired feature associated with higher biomass production, can be an important factor in selection programs.

Introduction Landfill leachate, a liquid resulting from waste decomposition, contains nutrients like ammoniacal-N, Na, K, and organic matter. Biological treatments effectively remove degradable organics from young landfill leachate, but aged leachate with recalcitrant organics requires combined physical-chemical and biological methods or advanced technologies, leading to higher treatment costs. Even after treatment, leachate may not meet environmental standards for release. In arid and semi-arid regions with water scarcity and low soil organic matter, leachate application to soil presents a potential solution. Soil’s properties enable it to retain and degrade pollutants while utilizing leachate’s nutrients to enhance fertility and crop growth. However, leachate composition and application rates are critical factors due to potential negative impacts from total nitrogen, salinity, and heavy metals. Alkaline pH in aged leachate reduces heavy metal contamination risk. Detailed leachate characterization before soil application is crucial to prevent environmental and functional problems. This review examines existing research on leachate irrigation’s effects on soil properties and plant nutrition, contributing to sustainable leachate management and agricultural practices in water-limited regions. Additionally, the review explores potential risks associated with leachate irrigation, including soil salinization, heavy metal accumulation, and groundwater contamination. By understanding both the benefits and drawbacks, informed decisions can be made regarding the suitability and implementation of leachate irrigation in specific contexts.   Materials and Methods To carry out this study, keywords such as "Landfill leachate", "Composition of landfill leachate" and "Landfill leachate irrigation" were searched in the Web of Science, Google Scholar, ScienceDirect, and SID databases. For these keywords, 205 articles were found from 1989 to 2023. After the screening, quality review, and removal of repetitive and unrelated articles, 110 relevant articles were used. The main criterion for selecting articles was the effects of landfill leachate irrigation on the various properties of soil, and the nutrition of different plant species. The quality of the articles was evaluated through the Scimago Journal Rank (SJR) index, the citation, the Impact Factor, and the source normalized impact per paper (SNIP) index.   Results and Discussion Landfill leachate presents a complex environmental challenge due to its potential for both soil contamination and enrichment. Leachate's xenobiotic and heavy metal components can induce soil contamination, altering the natural environment. Studies have documented reduced hydraulic conductivity, increased gas production, and altered microbial communities, ultimately impacting soil productivity.  Leachate percolation can also modify physicochemical characteristics, including reduced microbial biomass, phosphorus-fixing capacity, and pH shifts, depending on waste composition. Conversely, research highlights the potential benefits of leachate application in arid and semi-arid regions facing water scarcity and low soil organic matter. Leachate can contribute to the increased organic content, improved soil structure, and regulated pH, enhancing soil fertility and crop productivity.  The presence of macro and micro-nutrients such as Fe, Mn, N, P, and Zn further supports leachate's potential as a fertilizer. However, concerns remain regarding inhibitory chemicals in leachate and their potential detrimental effects on plant growth and yield. Studies report instances of leaf injury, reduced yield, and poor survival rates in certain plant species.  In contrast, research demonstrates the positive effects of diluted or low-strength leachate application, stimulating plant growth and enhancing yield, particularly for Brassica species and tree species like Acacia confusa, Leucaena leptocephali, and Eucalyptus tortellini. These contradictory findings underscore the intricate interplay of factors influencing leachate irrigation outcomes. Soil characteristics, plant species, leachate source and composition, application methods, and their interactions all play significant roles in determining the success or failure of leachate irrigation. Conclusion Landfill leachate, characterized by its elevated nitrogen and nutrient levels, presents a potential alternative water and fertilizer source for agricultural practices, particularly in arid and semi-arid regions facing water scarcity. However, responsible leachate utilization necessitates a comprehensive approach that balances maximizing benefits with minimizing environmental risks. Prior to agricultural application, detailed leachate characterization is crucial to determine its precise composition and suitability for irrigation. This includes quantifying heavy metal concentrations, salinity levels, and the presence of potentially toxic organic compounds.  Concurrent plant selection is equally important, prioritizing species with demonstrated tolerance to leachate constituents. Given the potential for salinity and heavy metal accumulation, continuous application of raw leachate, especially for sensitive crops, should be avoided. Implementing alternating irrigation regimes with conventional water sources can mitigate these risks while providing essential nutrients for plant growth.  Monitoring soil health indicators, including pH, organic matter content, and microbial activity, is vital to assess long-term impacts and implement necessary soil amendments. Determining optimal leachate application rates requires a multifaceted approach that considers plant-specific nitrogen requirements, leachate toxicity levels, and soil infiltration capacity.  This ensures adequate nutrient supply without exceeding the assimilative capacity of plants and soil, preventing environmental contamination. Further research is needed to investigate the long-term impacts of leachate irrigation on soil health, crop quality, and potential groundwater contamination. Developing standardized guidelines for leachate treatment and application, tailored to specific regional contexts and crop types, is crucial for promoting sustainable and responsible leachate utilization in agriculture.