Soil Micronutrients Research Articles

Food waste digestate as biofertilizer and their direct applications in agriculture

A useful way to reduce food waste (FW) environmental impact is by turning it into biofertilizer. The conversion of FW into biogas can be used for agricultural applications after being converted into biofertilizer through techniques such as anaerobic digestion (AD), composting, and vermicomposting. Through use of food waste digestate (FWD) as a biofertilizer, nutrient loops are closed and waste is reduced. Instead of dumping FW into landfills, which contributes to greenhouse gas emissions, the waste is processed into digestate and fed to plants, creating a sustainable cycle. In addition to enhancing soil micronutrients, reducing environmental pollution, and reducing the need for chemical fertilizers, FW biofertilizers contribute to the circular economy. There are several methods for applying FWD to agricultural fields, including surface spreading, injection, and incorporation into the soil. Technology for converting FW to biofertilizers is sustainable, and invention productivity can be increased through well-procedure regulatory approaches and innovative machinery.

Assessment of Physico-chemical Properties of Soil from Different Departments of NAI, SHUATS, Prayagraj, U.P., India

An Assessment of Physico-chemical properties of soil from different departments of NAI, SHUATS, Prayagraj carried out 2022-23. The prime objectives of this study were to carry out the physico-chemical properties of soil at different depths of various department research farms to determine the availability of macronutrients and micronutrients in soil of these soil sample provide the assessment 6 sampling locations were selected. Soil samples were collected with depth of 0-15 and 15-30 cm respectively. The soil colour dry condition varied from light yellowish brown, pale olive, light olive brown, yellowish brown, olive yellow, dark brown and in wet condition varied from olive brown, dark brown, olive yellow and dark yellowish. The sand, silt and clay varied from 53 to 65 %, 19 to 27 % and 15 to 20 % respectively, soil texture was dominantly sandy loam in every site. The bulk density ranged from 1.20 to 1.34 Mg m⁻3. The practical density ranged from 2.68 to 2.94 Mg m⁻3. The pore space ranged from 43.25 to 49.50 %. The water holding capacity ranged from 41.75 to 48.25 %. The soil pH ranged from 7.37 to 7.71. The electrical conductivity ranged from 0.21 to 0.48 dS m-1. The soil organic carbon ranged from 0.32 to 0.45 %. The available nitrogen ranged from 235.17 to 261.12 kg ha-1. The available phosphorous ranged from 19.66 to 25.50 kg ha-1. The available potassium ranged from 152.00 to 214.00 kg ha-1. The available Sulphur ranged from 8.80 to 14.42 mg kg-1. The available zinc ranged from 0.58 to 0.93 mg kg-1. The available boron ranged from 0.58 to 1.10 mg kg-1. The available iron ranged from 5.92 to 8.70 mg kg-1. The available manganese ranged from 3.21 to 3.61 mg kg-1. The available copper ranged from 2.00 to 2.94 mg kg-1. There is an including awareness of the need to pay greater attention in the role of macronutrients enhancement in the soil for good soil health and proper nutrition of plant so as to attain optimum economic yield and soil is suitable for all major tropical and sub-tropical crops.

Soil micronutrients and their functions

Soil micronutrients and their functions

Modeling and mapping the spatial variability of soil micronutrients in the Tigris basin

BackgroundCrop production is negatively impacted by excess and lack of soil micronutrients. Due to anthropogenic and natural factors, soil micronutrients vary greatly in space, necessitating time- and money-consuming large-scale sampling. Therefore, modeling their spatial distributions and forecasting in non-sampled areas are essential for high crop production. MethodsIn this study, regional variations in soil micronutrient content of the Upper Tigris Basin were modeled to produce local change maps for the development of site-specific nutrient management systems. The concentrations of extractable zinc (Zn), copper (Cu), manganese (Mn), and iron (Fe) in soil samples taken at 388 different sites between 0 and 20 cm deep were determined. Using variogram and kriging analyses, the spatial distribution of the micro element concentrations was modeled and mapped in a GIS environment. ResultsThe micronutrients demonstrated significant variability with a high coefficient of variation (CV > 35%). It was found that the spatial dependence of the samples ranged from low for Fe and Cu to high for Zn and Mn. The spatial distribution of soil micronutrients was influenced by soil texture in addition to distance. Overall, the results demonstrated that the management of site-specific micronutrients may be aided by the integration of geostatistics and GIS, which is particularly beneficial in terms of effective management of the lands and the optimal use of inputs. ConclusionOverall, the findings showed that the integration of geostatistics and GIS may be helpful in the management of site-specific micronutrients, which is especially advantageous in terms of efficient management of the lands and the best use of inputs.

Micronutrient Indexing of Soils Located in Attock District of Pakistan: A Guide to Replenish the Nutrient Deficiency

The agricultural land of Attock district falls in Pothwar area of the Punjab Pakistan which is mostly rainfed (barani) and agriculture in the area depends on rainfall which is erratic and scanty. Therefore, soil health becomes more crucial for crop growth while application of micronutrients is negligible in this area. During the years from 2016 to2018, 15,337 soil samples were collected from the district Attack to determine micronutrient status of the soil. These soil samples were analyzed for Zinc (Zn), copper (Cu), Iron (Fe) and Manganse (Mn) using DTPA extraction method while dilute HCl method for Boron (B). The results indicated that nutrient index value of plant available Zn was in the marginal category (1.84) with 30.7% soil samples falling in low, 54.1% in marginal and 15.2% in adequate category. Nutrient index value of plant available Cu was in the adequate category (2.18) with 16.9 % soil samples in low, 47.9% in marginal and 35.2% in adequate category. Nutrient index value of plant available Fe was 1.46 (low) where 76.8% soil samples were found to be low and 23.2% adequate. Nutrient index value of plant available Mn was 1.11 (very low) where 89.3% soil samples were low, 9.9% marginal and only 0.8% adequate. Nutrient index value of plant available B was also in very low category (1.25) with 74.2% soil samples low and 25.8% marginal. The results indicated depletion and low concentration of micronutrient in most soil of Attock district which ultimately urges the use of balanced fertilizer for higher crop yield.

Suitability of Different Extractants for Estimation of Cationic Micronutrients in Lateritic Soils of West Bengal

The present study was conducted at Institute of Agriculture (Palli Siksha Bhavana), Visva-Bharati West Bengal, India during 2019–20 to evaluate the extractability of different extractants for extraction of cationic micronutrients in lateritic soils of West Bengal under rice based cropping system. Fifty surface (0‒15 cm) samples were collected from rice-based cropping systems from five different blocks of Birbhum district. The pH of the soil was found extremely acidic to slightly acidic. The organic carbon content (%) were low to medium range. Among major nutrients available phosphorus and sulphur showed deficiency under study area. The micronutrients cations were extracted from the soils using five different extractants, namely, Mehlich 3, HCl, AB-DTPA and the conventional extractant DTPA. The greatest mean concentration for all the micronutrients was obtained by Melich 3 extractant followed by HCl whereas the lower values were obtained when DTPA extractant used. Themagnitude of extraction for all cationic micronutrients was Mehlich 3>HCl>AB-DTPA>DTPA. Melich 3 has a higher extractability due to its high pH and ability to displace exchangeable cations due to the presence of the NH4+ ion in the extractant. The low extractability of the DTPA extractant may be due to disruption of metal-chelate equilibria in acidic soils. A higher positive significant correlation observed among the extractants from the study indicated that, they were able to extract the micronutrients from remarkably similar pools.

Immobilization of Cr3+, Cd2+, and Pb2+ added to calcareous soil amended with composted agro-industrial residues

The bioavailability of trace metals in soils poses a major threat to the environment, especially with massive mineral fertilizers added to increase plant yield. A plot experiment was conducted for the effectiveness evaluation of compost and vermicompost, recycled from agro-industrial wastes, in immobilizing chromium, cadmium, and lead added to calcareous soil (artificially contaminated). Moreover, immobilization efficiency was compared to the natural occurrence of these metals in the soil without metal addition (uncontaminated soil). In both soils, amendments and mineral fertilizers were applied at three different levels alone and combined to each other. The experimental design was arranged in factorial complete randomized blocks using contamination, organic and mineral fertilizer levels, and their combination as categorical factors. The distribution of metal fractions and their bioavailability in soils and bioaccumulation in wheat grains were evaluated. Soil alkalinity, the contents of soil organic carbon and nitrogen, available phosphorus, and soil micronutrients were significantly improved under vermicompost and compost compared to mineral fertilizer and control. Vermicompost was more effective than compost in reducing metals bioavailability in contaminated soils by increasing the immobilized organic fractions, but it regressed when combined with mineral fertilizers. The bioavailability of the naturally occurring metal levels in uncontaminated soil did not change significantly compared to contaminated soil. Likewise, wheat yield, plant biomass, and nutrient enrichment in wheat grains improved due to enhanced soil nutrient availability. These composted agro-industrial residues, by-products from food industries, can be classified as environmentally-friendly soil amendments for their great potential to enrich soil nutrients, reduce mineral fertilizer addition, enhance plant growth, and stabilize Cr, Cd, and Pb in contaminated calcareous soils under wheat plants.

Effect of Inorganic and Integrated Long-term Nutrient Management on DTPA-extractable Micronutrients in a Vertisol under Soybean-wheat Cropping System across the Soil Depth

The status of DTPA extractable micronutrient (Zn, Cu, Fe and Mn) in response of continuous application of different inorganic and organic fertilizer combination in a 48 years old ongoing long-term fertilizer experiment (AICRP-LTFE) were investigated in Vertisol at Department of Soil Science, and Agricultural Chemistry, JNKVV, Jabalpur under intensive cultivation of soybean- wheat cropping system in 2021. The treatments selected for the study were: control (T1); 100% NP(T2); 100% NPK (T3); 100% NPK+FYM (T4); 100% N(T5); 50% NPK (T6); 150% NPK (T7). Application of FYM along with balance fertilizer (100% NPK) significantly increased the micronutrients availability in soil. On contrast, Imbalance fertilization caused a lower level of micronutrients in soil even below to the critical limit in case of zinc. A decreasing trend with increase in soil depth irrespective of type of nutrient management and micronutrient type was evident in the study. Findings of the present study emphasized the application of balance fertilization along with organic sources like FYM for sustaining micronutrients availability in Vertisol under soybean-wheat cropping system.

Performance of moringa (Moringa oleifera) and soil health under organic nutrition

A field trial was conducted during 2016–17, 2017–18, 2018–19 and 2019–20 at the Main Horticultural Research and Extension Centre, Bagalkot under Northern Dry Zone-3 of the Agroclimatic zones of Karnataka with an intention to study the response of moringa (Moringa oleifera L.) crop to different organic sources of nutrients. There were five nutrition treatments, viz. T1, 100% RDN through FYM; T2, 100% RDN through vermicompost; T3, 100% RDN through neem cake; T4, 1/3 RDN through FYM+1/3 RDN through vermicompost+1/3 RDN through neem cake and; T5, 50: 125: 30 kg NPK+20 tonnes FYM/ha (RDF) and replicated four times. The treatment T4 recorded significantly higher green pod yield (87.99 q/ha) which was on par with RDF (83.83 q/ha) and T3 (82.66 q/ha). However, most of the growth (except height) and yield contributing parameters, in all the organic treatments, were on par with RDF.Application of organic manures helped in improving available nutrients status, including micronutrients in soil. Among the different organic manures, the effect of FYM and VC in increasing the population of rhizosphere microorganisms was more than other treatments. Net return was found more in T4 (`124446/ha) followed by T3 (`118179/ha) and RDF (`114079/ha). It was found that organic manure applied in equal proportion (T4) and 100% substitution of N through neem cake (T3) was found better in getting higher yield and returns.

Spatial variability of soil micronutrients under paddy (Oryza sativa)-wheat (Triticum aestivum) cropping system in irrigated plains

Soil properties vary spatially over short distances and sometimes prove detrimental to crop productivity in farmlands even after uniform application of balanced nutrients. In the present study, spatial variability of micronutrients was studied in Chakroi farm of Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu (SKUASTJammu) during 2016 and 2017. Results indicated that mean concentrations of micronutrients were in the order of Fe > Mn > Cu > Zn both in surface and sub-surface layers. Exponential model was the best fit for all micronutrients in surface soil layer. Linear model was best fit for Cu and Gaussian model for Mn in the sub-surface layer. Whereas for Zn and Fe, the best fit was defined by exponential model. All the four micronutrients showed strong spatial dependence in surface layer, whereas in sub-surface layer Mn and Zn showed strong spatial dependence as compared to Cu. More than 60% of the area in the surface layer had Cu in the range of 2.0–2.8 mg/kg of soil. A very small area was under high range on the eastern side of the farm while in the sub-surface layer, Cu was unevenly distributed. The soil maps of Zn showed that it is above the critical value in surface layer while in sub-surface layer nearly 40% of the area had Zn in the deficient range. Fe was unevenly distributed and in the sub-surface layer it was higher in the southern and north-western parts of the farm. Mn was above the critical limit in both surface and sub-surface soils of the farm.

Developing regional soil micronutrient management strategies through ensemble learning based digital soil mapping

Mapping of soil micronutrient variability is critical for improving agronomic biofortification. This study used 1778 surface soil samples collected from four agro-climatic regions of the Indo-Gangetic Plain of India to produce digital soil maps of available Zn, Cu, Fe, and Mn using 52 environmental covariates at a resolution of 150 m. The micronutrient prediction accuracy was compared for 14 machine learning approaches and their ensemble model. The hybrid ensemble model outperformed all 14 base learners and was subsequently used for producing micronutrient maps. All four micronutrients exhibited sufficient spatial variability. Both available Zn and Fe maps exhibited lower prediction uncertainties. Moreover, the inter-relationship between micronutrient concentration in soil and rice grain was explored to understand the Zn and Fe biofortification potential. The linear regression models revealed moderate agreement between soil available and grain micronutrient concentrations, with R2 values of 0.52–0.63 for Zn and Fe, respectively. The developed models were used to predict grain Zn and Fe content from their respective soil concentrations, indicating the potential of the tested approach to identify specific pockets where rice varieties with biofortification potential can be planted. In the future, the digital soil mapping approach tested herein can help policymakers with regional decision-making, encouraging nutrient-based subsidy and investment opportunities and sustainable micronutrient recommendations toward micronutrient-enriched food. Further research is needed to develop a digital soil intelligence platform using micronutrient DSM products in resource-poor countries.

Short-Term Biochar Impacts on Crop Performance and Soil Quality in Arid Sandy Loam Soil

A two-year field study was conducted in sandy loam soil to evaluate the impacts of biochar on soil quality and the growth and yields of pinto bean (Phaseolus vulgaris) and sorghum–Sudan (Sorghum × drummondii). A wood-derived commercial biochar was applied at three rates to pinto bean (PB) and sorghum–Sudan (SS) plots. The biochar application rates applied annually for two years to PB plots were 0, 2.2, and 11.2 Mg ha−1, whereas the rates for SS plots were 0, 3.4, and 6.7 Mg ha−1. Crop growth and harvest parameters were evaluated. Assessed soil measurements included pH, electrical conductivity, available nutrients, soil organic matter (SOM), permanganate oxidizable carbon (POXC), soil aggregates, and volumetric soil moisture content. The results showed no significant differences in plant growth parameters and yields over the two growing seasons for both PB and SS. Compared to the control treatment, the biochar at 11.2 Mg ha−1 in PB plots improved soil moisture retention after irrigation by 19% in the first year and 25% in the second year. The SOM in the SS plot at 6.7 Mg ha−1 biochar rate was higher (1.02%) compared to the control plot (0.82%), whereas a similar increase was not observed in the PB plot. Although biochar rates did not affect most of the soil measurements, there were significant changes in soil properties over time, regardless of biochar treatments: POXC increased in the PB and SS plots; SOM increased in the SS plot; and electrical conductivity, sodium adsorption ratio, and most soil micronutrients decreased. This research was conducted over two years; the effects of biochar can persist for much longer, indicating the need for longer-term biochar field studies in arid agroecosystems.

Explaining the Soil Quality Using Different Assessment Techniques

Soil quality serves as the basis for both food security and environmental sustainability. To optimize production and implement soil management interventions, understanding the state of the soil quality is fundamental. Thus, this study was conducted to assess the soil quality of arable lands situated in the Nitisols and Luvisols using different assessment techniques. A total of 57 georeferenced soil samples were taken at a depth of 20 cm (18 from Nitisols and 39 from Luvisols land). The soil samples were analyzed for particle size distribution (PSD), texture, pH, organic carbon (OC), total nitrogen (TN), available phosphorus (P), sulfur (S), exchangeable bases (calcium (Ca), magnesium (Mg), and potassium (K)), soil micronutrients (boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn)), and cation exchange capacity (CEC). The techniques used to estimate soil quality includes principal component analysis (PCA), a normalized PCA, and common soil parameters (soil texture, pH, OC, N, P, and K). The results were expressed in terms of soil quality index (SQI). In addition, the soil fertility/nutrient/index (NI) approach was used. The result showed that the SQI values using the common parameters approach were 0.17 and 0.30 for the lands belonging to Nitisols and Luvisols and categorized as very poor (<0.2) and poor (0.2–0.4) quality soils, respectively. PCA-SQI and normalized PCA-SQI values for lands in the Nitisols were 0.36 and 0.42, while for Luvisols they were 0.38 and 0.40, respectively. The soil quality of lands in the Luvisols was rated low (0.38–0.44), while lands in the Nitisols qualified under very low (<0.38) and low soil quality, respectively. In addition, the value of 1.42 and 1.78 in their order for lands belonging to Nitisols and Luvisols were recorded using the NI method that indicated low and medium soil quality. In conclusion, PCA and common soil parameters techniques regardless of soil types offered consistently similar information and could be taken as useful techniques for aiding soil management interventions. Furthermore, the result also calls for the need for applying soil management practices.

The Impact of Integrated Nutrient Management Practices on Post-harvest Soil Micronutrient Status of Upland Paddy

The Impact of Integrated Nutrient Management Practices on Post-harvest Soil Micronutrient Status of Upland Paddy

Shifts in functional traits and interactions patterns of soil methane-cycling communities following forest-to-pasture conversion in the Amazon Basin.

Deforestation threatens the integrity of the Amazon biome and the ecosystem services it provides, including greenhouse gas mitigation. Forest-to-pasture conversion has been shown to alter the flux of methane gas (CH4 ) in Amazonian soils, driving a switch from acting as a sink to a source of atmospheric CH4 . This study aimed to better understand this phenomenon by investigating soil microbial metagenomes, focusing on the taxonomic and functional structure of methane-cycling communities. Metagenomic data from forest and pasture soils were combined with in situ CH4 fluxes and soil edaphic factors measurements and analysed using multivariate statistical approaches. We found a significantly higher abundance and diversity of methanogens in pasture soils. As inferred by co-occurrence networks, these microorganisms seem to be less interconnected within the soil microbiota in pasture soils. Metabolic traits were also different between land uses, with increased hydrogenotrophic and methylotrophic pathways of methanogenesis in pasture soils. Land-use change also induced shifts in taxonomic and functional traits of methanotrophs, with bacteria harboring genes encoding the soluble form of methane monooxygenase enzyme (sMMO) depleted in pasture soils. Redundancy analysis and multimodel inference revealed that the shift in methane-cycling communities was associated with high pH, organic matter, soil porosity, and micronutrients in pasture soils. These results comprehensively characterize the effect of forest-to-pasture conversion on the microbial communities driving the methane-cycling microorganisms in the Amazon rainforest, which will contribute to the efforts to preserve this important biome.

Spatio-temporal variability of available sulphur and micronutrients (Zn, Fe, Cu, Mn, B and Mo) in soils of a hilly region of northern India

Knowledge about spatio-temporal variabilities of plant available (hereafter called available) nutrients in soils is important for undertaking revised and efficient site-specific soil nutrient management practices in order to achieve higher crop production and nutrient use efficiency in different parts of the world. Despite emerging deficiencies of available sulphur (AS) and micronutrients in various soil-crop situations, the information pertaining to temporal changes in spatial variability of AS and available micronutrients in soils of different parts of the world is limited due to scarce studies in the said area. The present study was carried out to assess and compare the status and spatial as well as temporal distribution pattern of AS, available micronutrients, and some selected soil properties [soil pH, electrical conductivity (EC), and soil organic carbon (SOC)] in cultivated soils of a hilly region of India, in 6 years (2015–2021). We also visualized correlations among soil properties, AS, and available micronutrients, and studied spatial structures of the soil parameters. We collected altogether 2, 871 (1, 127 in 2015 and 1, 774 in 2021) georeferenced representative topsoil (0–15 cm depth) samples from cultivated areas of Uttarakhand state of India and analysed. Soil properties, AS and available micronutrients exhibited moderate variability with coefficient of variation (CV) values ranging from 10 to 100%. The mean values of AS and available micronutrients in 2015 and 2021 differed significantly, as revealed by t-test. The mean concentrations of AS (13.2 mg kg−1), available iron (AFe) (36.5 mg kg−1), available boron (AB) (0.92 mg kg−1) and available molybdenum (AMo) (0.40 mg kg−1) in 2021 were significantly lower than the concentrations of AS (44.7 mg kg−1), AFe (42.8 mg kg−1), AB (1.46 mg kg−1), and Amo (0.94 mg kg−1) in 2015. The AS concentration was positively and significantly correlated (r = 0.064 p < 0.05 in 2015, r = 0.261 p < 0.01 in 2021) with soil pH and negatively and significantly correlated (r = −0.082 p < 0.01 in 2015, r = −0.125 p < 0.01 in 2021) with SOC in both the years. There were positive and significant correlations of SOC with available zinc (AZn) (r = 0.111 p < 0.01), available copper (ACu) (r = 0.062 p < 0.05) and AB (r = 0.159 p < 0.01) in 2015 and with AZn (r = 0.101 p < 0.01), AFe (r = 0.187 p < 0.01), ACu (r = 0.164 p < 0.01), available manganese (AMn) (r = 0.169 p < 0.01) and AMo (r = 0.266 p < 0.01) in 2021. The exponential model was found to be best fitted for all of soil parameters with lower MSE values (−0.007 to 0.006 in 2015 and −0.010 to 0.012 in 2021) in both the years of estimation. The nugget/sill ratios (varied from 0.32 to 0.74 in 2015 and from 0.29 to 0.57 in 2021) indicated the moderate spatial dependence for all the soil parameters except AFe (nugget/sill ratio 0.14, strong spatial dependence) in 2015 and EC (nugget/sill ratio 0.24, strong spatial dependence) in 2021.There were varied distribution patterns of soil properties, AS and available micronutrients in the study area for both the years of estimation. The distribution patterns of AS, AB and AMo changed to a greater extent over the period of time. Thus, the study highlighted the change in spatial variability of AS and available micronutrients in the study area over a period of 6 years.

Comparative assessment of selected micronutrients under three different land use systems in Odighi, Edo State, Nigeria

This study carried out a comparative assessment of selected micronutrients under mixed tree plantation, cassava and secondary forest land use systems in Odighi, Edo State, Nigeria. The objectives of the study were to determine the concentrations of selected micronutrients under each of the three land use systems; evaluate the distribution of these micronutrients among the three land use systems; and examine the impact of the three land use systems on the selected micronutrients. Using transect sampling design, 18 soil samples were collected from each of the three land use systems giving a total of 54 soil samples for the study. The cassava land use was 7-10-year-old, mixed tree plantation was 10-15-year-old, while secondary forest was 25-year-old and above. Results showed that the concentrations of the selected soil micronutrients (iron, copper, manganese, and zinc) increased with increasing soil depth in all the examined sites except for manganese under cassava land use. The status of iron and zinc were rated excess while copper and manganese were rated optimum for crop production. The study observed significant (p &lt; 0.05) variations for iron and manganese contents across the examined land uses and concluded that the direction and magnitude of changes in the status of micronutrients were a reflection of long-term impact of the different land uses and soil management measures. Liming of the soil and limited use of nitrogen-containing fertilizers are recommended to ameliorate zinc toxicity in the study area. Also, farmers in collaboration with agriculture extension workers should regulate the usage of organic and inorganic fertilizers as soil treatments to avoid excessive concentrations of iron and zinc in the study area.

Effect of Nano-Phosphorus Formulation on Growth, Yield and Nutritional Quality of Wheat under Semi-Arid Climate

Appropriate phosphorus (P) management techniques increase yield and nutritional properties while minimizing environmental concerns. The widespread use of nano-fertilizers (NFs) in agriculture endangers soil and plants. It is vital to research the behavior of nano-phosphors (nano-P) on plant growth and quality, as well as their technique of interaction with soil properties in order to obtain key ecosystem benefits. With this in mind, a field experiment was conducted using wheat as a test crop to explore the impact of nano phosphorus (nano-P) on soil. The study’s goal was to examine how the foliar application of nano-P to wheat affects its growth, yield and nutrient concentration. Treatments consisted of: T1: 100% NPK (120:137:72 kg N:P2O5:K2O ha−1) by RDF (recommended dose of fertilizer); T2: 100% NPK by RDF + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T3: 100% NK + 0% P (no foliar); T4: 100% NK + 75% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T5: 100% NK + 50% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1;T6: 100% NK + 0% P + 2 foliar sprays of nano-P @ 494.21 mL ha−1; T7: 100% NPK by RDF + 1 foliar spray of nano-P @ 494.21 mL ha−1; T8: 100% NK + 75% P + 1 foliar spray of nano-P @ 494.21 mL ha−1; T9: 100% NPK + 1 foliar spray of nano-P @ 494.21 mL ha−1; T10-100% NK + 75% P + 1 foliar spray of nano-P @ 494.21 mL ha−1. According to the findings, applying 100% NK + 75% P + 2 foliar applications of nano-P at the tillering and panicle initiation stages increased yield over 100% RDF by 37.1%. Additionally, the highest micronutrient concentration (Zn (36.4 mg kg−1), Cu (21.2 mg kg−1), Mn (22.9 mg kg−1) and Fe (61.1 mg kg−1)) in grain were noticed in T3 (100% NK + 0% P no foliar spray of nano-P) treatment, which was superior to T1 (100% NPK). Furthermore, foliar application of nano-P fertilizer in combination with different levels of diammonium phosphate (DAP) slightly increased the amount of N, P and K, as well as micronutrients in post-harvest soil. In summary, the use of 100% NK + 75% + 2 foliar applications of nano-P saved 25% recommendation dose P if supplied as nano-P as a form of phosphorus, and can be a suitable substitute for DAP, especially in smart agriculture, as it possibly reduces P leaching into groundwater, while maintaining or increasing wheat crop yield over the 100% RDF.

Variability analysis of soil properties, mapping, and crop test responses in Southern Ethiopia

Agricultural productivity is significantly impacted by soil properties, which vary spatially from a small to a larger area. This variation may be caused by a combination of intrinsic and extrinsic factors, including human activities like soil management practices. The aim of the current study was to analyze soil spatial variability, create a Digital Soil Map (DSM), and test map information with crop in Southern Ethiopia. A total of 18 geo-referenced surface soil samples at depth of 20 cm were collected. Selected soil Physico-chemical properties such as soil texture, pH, organic carbon (OC), total nitrogen (TN), available phosphorus (av. P), sulfur (S), exchangeable bases [calcium (Ca), magnesium (Mg), and potassium (K)], soil micronutrients [boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn)] and cation exchange capacity (CEC) were analyzed. The results revealed clay texture with a mean pH value of 4.6 (strong acidity). About 50% of essential nutrients [N, P, S, Ca, Mg, B & Fe] were deficient. The geostatistical analysis has shown that the best-fitted models were exponential for (OC, TN, available P, S, Mg, CEC, B, Fe, and Zn), spherical for (pH, Ca, Cu and Mn), and Gaussian for (C:N, K, K:Mg, and PBS). The range of all soil properties varied from 50 m to 84 m which was above the actual distance between soil samples (i.e., 46 m). The result showed that the spatial dependence values for soil properties of [OC, TN, CEC, PBS, ESP, and Cu]; [pH, C: N ratio, available P, S, Ca, Mg, K, Na, K: Mg ratio and Zn] and [B, Fe, M n] were strong (<25%]; weak (>75%) and moderate (25%–75%), respectively. Model performance using indicators such as prediction mean error (PME), root mean square standardized error (RMSSE), mean standard error (MSE), and root-mean-square error (RMSE) also confirmed the acceptable prediction. The DSM demonstrated the limitation of N, P, S, and B nutrients for intervention. The DSM information was tested under field conditions using haricot bean (Phaseolus vulgaris) with lime and organic fertilizers as treatments. The experiment consists of lime rates (0, 3, 6 t/ha), rhizobium inoculation (inoculated and non-inoculated), and fertilizer types (0, 150 kg ha−1 NPSB, 5 t/ha vermi compost, 10t/ha farmyard manure (FYM)) in Randomized Complete Block Design with three replications. The result exhibited interaction effects of lime, inoculation, and fertilizer types significantly influenced (p < 0.05) biomass and grain yield of haricot beans. Rhizobium inoculation x 6t/ha lime x 150 kg ha−1 NPSB recorded the maximum grain yield (3186.1 kg/ha) which was 26.3 fold over the non-treated soil (117 kg ha−1). In conclusion, the DSM classified the area into distinct management zones which were tested with a crop trial. The results of the trial confirm the importance of site-specific nutrients/amendment application for sustainable soil management.

Influence of Zinc and Boron on Physico-chemical Properties of Soil under Maize Crop in an Inceptisol of Prayagraj, Uttar Pradesh, India

The research was conducted during the Rabi 2020-2021 and 2021-2022. The experiment was laid out in Randomized Block Design with sixteen treatments and three replications with four levels of Zinc and Boron along with NPK as RDF. The non-significant findings were B.D, P.D, % pore space, water holding capacity, and pH were as, the present macro- micro nutrients in soil and also the morphological parameters have significant findings which comprises color is yellowish brown sandy loam textured neutral to alkaline soil that is non- saline in nature among all the treatment combination applied. The OC, NK observed significantly medium to high in treatment T16 RDF (120:60:40 NPK kg ha-1) + Zinc@20 kg ha-1+ Boron @5 kg ha-1), micro-nutrients such as Zinc, Boron were knowingly medium to high in T16 RDF (120:60:40 NPK kg ha-1) + Zinc@20 kg ha-1+ Boron @5 kg ha-1). The maximum mean value for bulk density (1.33 Mg m-3), particle density (2.589 Mg m-3) percent pore space (47.98%), and percent maximum water holding capacity (45.87%) were found. The chemical soil parameters with a cumulative mean of slightly saline soil pH (7.93), average Electrical conductivity (0.41 dS m-1), maximum percent OC (0.42), high Available N (288.52 kg ha-1), high Available P in T2 (16.85 kg ha-1) due to the antagonistic effect of zinc on Phosphorous, high Available K (207.98 kg ha-1), high Available Zn (1.144 mg kg-1), and high Available B (1.243 mg kg-1) were categorized in evaluation to other NPK and micronutrients levels treatments.