Urea Application Research Articles

Effect of Planting Geometry and Inorganic Fertilizers with Nano Urea Quality and Nutrient Uptake of Rice Crop (Oryza sativa L.)

The present investigation entitled “Influence of planting geometry and inorganic fertilizers with nano urea on productivity of rice crop (Oryza sativa L.).” was conducted at Agronomy Research Farm of Narendra Deva University of Agriculture and Technology, Narendra Nagar (Kumarganj), Faizabad-224229 (U.P.) during Kharif seasons of 2022 and 2023. Fifteen treatment combinations comprised of three planting geometry C1 (20 cm × 10 cm), C2 (20 cm × 15 cm) and C3 (20 cm × 20 cm) in main plot with five fertility levels F1 - 100% RDF (150:60:40), F2 [100% RDF + Two foliar spray of nano urea @ 3000 ml ha-1(Tillering and Panicle initiation stage)], F3 [75% RDF + Two foliar spray of nano urea @ 3000 ml ha-1(Tillering and Panicle initiation stage)], F4 [50% RDF + Two foliar spray of nano urea @ 3000 ml ha-1(Tillering and Panicle initiation stage)] and F5 - Control [no fertilizers] were executed in split plot design keeping fertility levels in sub plot with three replications. The soil of experimental plot was silty loam in texture with low in orgainic carbon and nitrogen médium in phosphorus and high in potassium. The treatment combination C1 (20 cm × 10 cm) along with F2 [100% RDF + two foliar applications of nano urea at 3000 ml ha-1 (during Tillering and Panicle initiation stages)] demonstrated significantly elevated levels of quality and nutrient uptake, including protein content (%), yield (kg ha-1), NPK content (%), and NPK uptake (kg ha-1). This performance was comparable to the combination of C1 (20 cm × 10 cm) with F3 [75% RDF + two foliar applications of nano urea at 3000 ml ha-1 (during Tillering and Panicle initiation stages)], and notably surpassed other treatments. In summary, the utilization of C1 (20 cm × 10 cm) coupled with F2 [100% RDF + foliar spray of nano urea @ 3000 ml ha-1 (during Tillering and Panicle initiation stages)] exhibited superior outcomes across all parameters of quality and nutrient absorption, leading to increased rice crop yield and profitability over both study years.

Liquid Nano Urea: Step Forward to Smart Agriculture- A Review

Chemical fertilizer is necessary for the growth and development of crops. However, the efficiency of conventional chemical fertilizers is very low. Nowadays, fertilizer use efficiency (FUE) is the focus of agriculture cultivation practices to meet economic and environmental challenges. Around half of the total agricultural production relies on urea fertilizer, and the reduction in soil fertility has led to 3.56%. Liquid Nano Urea (LNU) can play a vital role in ensuring food security in Bangladesh. It can replace 50 % of conventional urea and can save subsidies to the govt. In addition, it is environmentally safe and reduces production costs, ensuring an increase in the total yield of 8-20%. Ensuring 90% work efficiency, the utilization of cutting-edge technologies and modern innovation in agricultural practices to enhance sustainability and efficiency in farming. Only two sprays of LNU can change the whole scenario of food safety. Recommended dose of optimize the use of nano urea for improved crop productivity and sustainability. The proper application of nano urea holds immense potential for enhancing crop production efficiency and sustainability.

Effects of Applying Different N Sources on Cd Accumulation, Mineral Micronutrients, and Grain Yield of Durum Wheat

This study aimed to investigate the effects of different nitrogen sources on Cd concentration in durum wheat grains in soils with low and high Cd contamination. Triticum turgidum L. durum, cv. Balcali-2000 was sown as test plant material in plastic pots containing 3.2 kg of soil. Low (0.5) and high Cd (5.0 mg Cd kg− 1 soil) were added to the culture media in the form of 3(CdSO4).8H2O. Nitrogen was also added in the form of Ca(NO3)2.4 H2O in low, sufficient, and high concentrations. In addition, a foliar application of 0.5% urea was used as a further nitrogen supply. The results showed that the total nitrogen content and the Cd concentration of the grains increased with increasing nitrogen application. This increase was more pronounced with a combination of soil nitrogen and foliar urea. While the Cd concentration in the grains was 354 µg kg− 1 at low soil Cd concentration and insufficient nitrogen supply, the Cd concentration in the grains increased by 40% to 498 µg kg− 1 at low Cd concentration and high nitrogen supply. This increase in Cd concentration in the grains was 32% higher under high nitrogen applications than at high Cd-insufficient conditions. In addition, foliar application of urea to durum wheat leaves at low soil Cd concentrations increased the Cd concentration in the grains from 354 µg kg− 1 to 484 µg kg− 1. This study showed that different treatments and amounts of nitrogen sources can affect the uptake and accumulation of Cd in wheat grains at different Cd levels.

15N-DNA stable isotope probing reveals niche differentiation of ammonia oxidizers in paddy soils

Chemoautotrophic canonical ammonia oxidizers (ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB)) and complete ammonia oxidizers (comammox Nitrospira) are accountable for ammonia oxidation, which is a fundamental process of nitrification in terrestrial ecosystems. However, the relationship between autotrophic nitrification and the active nitrifying populations during 15N-urea incubation has not been totally clarified. The 15N-labeled DNA stable isotope probing (DNA-SIP) technique was utilized in order to study the response from the soil nitrification process and the active nitrifying populations, in both acidic and neutral paddy soils, to the application of urea. The presence of C2H2 almost completely inhibited NO3−-N production, indicating that autotrophic ammonia oxidation was dominant in both paddy soils. 15N-DNA-SIP technology could effectively distinguish active nitrifying populations in both soils. The active ammonia oxidation groups in both soils were significantly different, AOA (NS (Nitrososphaerales)-Alpha, NS-Gamma, NS-Beta, NS-Delta, NS-Zeta and NT (Ca. Nitrosotaleales)-Alpha), and AOB (Nitrosospira) were functionally active in the acidic paddy soil, whereas comammox Nitrospira clade A and Nitrosospira AOB were functionally active in the neutral paddy soil. This study highlights the effective discriminative effect of 15N-DNA-SIP and niche differentiation of nitrifying populations in these paddy soils.Key points• 15N-DNA-SIP technology could effectively distinguish active ammonia oxidizers.• Comammox Nitrospira clade A plays a lesser role than canonical ammonia oxidizers.• The active groups in the acidic and neutral paddy soils were significantly different.Graphical

Modeling maize growth and nitrogen dynamics using CERES-Maize (DSSAT) under diverse nitrogen management options in a conservation agriculture-based maize-wheat system

Agricultural field experiments are costly and time-consuming, and often struggling to capture spatial and temporal variability. Mechanistic crop growth models offer a solution to understand intricate crop-soil-weather system, aiding farm-level management decisions throughout the growing season. The objective of this study was to calibrate and the Crop Environment Resource Synthesis CERES-Maize (DSSAT v 4.8) model to simulate crop growth, yield, and nitrogen dynamics in a long-term conservation agriculture (CA) based maize system. The model was also used to investigate the relationship between, temperature, nitrate and ammoniacal concentration in soil, and nitrogen uptake by the crop. Additionally, the study explored the impact of contrasting tillage practices and fertilizer nitrogen management options on maize yields. Using field data from 2019 and 2020, the DSSAT-CERES-Maize model was calibrated for plant growth stages, leaf area index-LAI, biomass, and yield. Data from 2021 were used to evaluate the model's performance. The treatments consisted of four nitrogen management options, viz., N0 (without nitrogen), N150 (150 kg N/ha through urea), GS (Green seeker-based urea application) and USG (urea super granules @150kg N/ha) in two contrasting tillage systems, i.e., CA-based zero tillage-ZT and conventional tillage-CT. The model accurately simulated maize cultivar’s anthesis and physiological maturity, with observed value falling within 5% of the model’s predictions range. LAI predictions by the model aligned well with measured values (RMSE 0.57 and nRMSE 10.33%), with a 14.6% prediction error at 60 days. The simulated grain yields generally matched with measured values (with prediction error ranging from 0 to 3%), except for plots without nitrogen application, where the model overestimated yields by 9–16%. The study also demonstrated the model's ability to accurately capture soil nitrate–N levels (RMSE 12.63 kg/ha and nRMSE 12.84%). The study concludes that the DSSAT-CERES-Maize model accurately assessed the impacts of tillage and nitrogen management practices on maize crop’s growth, yield, and soil nitrogen dynamics. By providing reliable simulations during the growing season, this modelling approach can facilitate better planning and more efficient resource management. Future research should focus on expanding the model's capabilities and improving its predictions further.

Application of Urea and Ammonium Nitrate Solution with Potassium Thiosulfate as a Factor Determining Macroelement Contents in Plants

The following research hypotheses were established in this study: the applied urea and ammonium nitrate solution with potassium thiosulfate (UAN-KTS) has a positive effect on the chemical composition of spring wheat, spring rape and maize; fertilization with nitrogen, potassium and sulfur increases their contents in the usable parts of plants; the forms of applied fertilizers reduce the antagonistic effect of nitrogen and potassium on the content of other elements in plants. Two doses of nitrogen (N 1—optimal dose of nitrogen for a plant species; N 2—25% lower dose of nitrogen) and different ratios of N:K:S elements (N:K:S—without K and S; N:K1:S1—a narrowed ratio; N:K2:S2—the optimal ratio; N:K3:S3—an expanded ratio) were applied. The experiment was carried out on two soils of different quality. The improved soil quality resulted in a significant increase in the calcium (as opposed to magnesium) content of the three crops, in the nitrogen and sulfate–sulfur (VI) content of spring wheat grain and spring rapeseed, and in the phosphorus content of spring rapeseed and maize aerial parts. Reducing the dose (N 2) had a negative effect on the nitrogen content of spring wheat and on the sulfate–sulfur (VI) content of spring rape, maize and especially spring wheat. Increasing the N:K:S ratio had a small but usually antagonistic effect on the nitrogen content of all plant species, but a synergistic one on the potassium content of spring wheat, maize and partly of spring rape, and especially on the content of sulfate–sulfur (VI) in the crops. The effect of type of soil and fertilizers with different N:K:S ratios on the content of other macronutrients was related to plant species. The new fertilizer with the N:K2:S2 ratio had the greatest effect on the content of the tested macronutrients in spring wheat, spring rape and maize. In order to confirm the obtained relationships, it seems justified to carry out field experiments and studies with other plant species.

Polypeptide urea increases rice yield and nitrogen use efficiency through root growth improvement

ContextElucidating rice root growth and development characteristics is essential for improving nitrogen use efficiency (NUE) and grain yield (GY) of crops, particularly in light of innovations such as polyaspartic acid (PASP)–urea formulations. However, the effectiveness of PASP–urea on the morphological properties of rice roots is insufficiently explored. ObjectiveWe aimed to examine the effect of PASP–urea on root morphology properties, NUE, and grain yield of mid-season rice in southwest China. MethodsIn 2016 and 2017, a two-factor randomized block design experiment was conducted in Sichuan, China, during the rice planting season. Three N treatments: no N (control), conventional urea [CU], and polyaspartic acid–urea [PU] were administered to two rice varieties: Yixiangyou 2115 and Fyou 498. ResultsOur findings showed that grain yield and nitrogen recovery efficiency (NRE) of rice were closely related to the root surface area density (RSAD), root length density (RLD), and root volume density (RVD) of rice. Compared to the CU treatment, the PU application significantly boosted the root dry matter weight, RLD, RVD, and RSAD of both varieties by 12.00–16.87 %, 0.16–28.98 %, 12.41–37.06 %, and 8.14–33.66 % at the jointing, heading, and maturity stages, respectively. This contributed to a 0.37–15.63 % and 23.45–48.12 % increase in grain yield and NRE, respectively, in both years, and a 12.26–15.69 % increase in N partial productivity efficiency (NPPE) in 2017 by improving the effective panicle number per unit area, spikelets per panicle, and N uptake. ConclusionNRE and grain yield of rice were significantly increased by PU application by improving the rice root system. ImplicationsThe study findings offer insight on how PASP–urea application influences the root morphology of rice and its relationship with grain yield and NRE while offering novel strategies and concepts for optimizing N use in rice cultivation.

The Effect of Mannitol and Nano Urea on Terminal Heat Stress on Wheat (Triticum aestivum L.)

The present investigation was conducted during Rabi season, 2022-23 & 2023-24 at the student instructional farm (SIF) of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya- 224229 (U.P.). The experiment was conducted in randomized block design with three replications, seven treatments and wheat variety (HD 2967). The treatment was comprised of control distilled water spray, Mannitol 25, 50, 100 ppm and Nano urea 25, 50, 100 ppm respectively, which was foliar sprayed at 30 DAS. The observations have been studied on growth, bio-chemical, yield and yield attributes of wheat. Observations were recorded at 60, 90 DAS and at maturity stages for timely sowing (15 November) and late sowing (15 December). However, yield and yield parameters were taken at the time of harvesting of the crop. Foliar spray of mannitol and nano urea were performed well at 60, 90 DAS and at maturity parameters. Foliar application of nano urea with 25 ppm was recorded superior on plant height (cm), dry weight plant-1 (g), chlorophyll content in leaves (SPAD value), Catalase activity (g-1 fresh weight min-1), Peroxidase activity (mg g-1 fresh weight min-1), Super oxide dismutase activity (mg g-1 fresh weight min-1) However, yield and yield attributes viz length of spike, number of tillers plant-1, number of grains spike-1, grain yield plant-1 It is concluded from the result that foliar spray of nano urea 25 ppm was found most effective to increasing all characters and yield parameters of wheat.

Alterations in the Nutrient Status of Soil and Enzymatic Activity of Finger Millet Cultivated Soil Accompanying to Nano Urea Application

An experiment was conducted at the Zonal Agricultural Research Station, Gandhi Krishi Vigyan Kendra, University of Agricultural Sciences, Bangalore, with the aim of assessing the impact of nano nitrogen on growth, yield, nutrient uptake, nitrogen use efficiency and enzymatic activity in finger millet cultivation. Among different treatments, application of 75% RDN + seed treatment with nano urea + foliar spray of nano urea at 30 and 50 DAS showed significant improvements in various growth and yield parameters of finger millet. At 90 DAS, it resulted in a remarkable increase in the number of leaves hill-1 (36.73), leaf area (982.90 cm2 hill-1) and leaf area index (3.28). The treatment also led to enhanced growth indices viz., absolute growth rate of 0.74 g day-1, a relative growth rate of 0.029 g g-1 day-1 and a crop growth rate of 24.80 g m2 day-1 during 60-90 DAS period. Significantly, it boosted the grain yield of 3,397 kg ha-1 for finger millet over control. Notably, this treatment exhibited higher NPK (86.56, 25.93 and 55.36 kg ha-1 respectively) uptake at harvest. It also demonstrated superior agronomic efficiency, internal utilization efficiency and nutrient increment efficiency of nitrogen (52.57, 39.24 and 1.40 kg kg-1 respectively). These findings underscore the potential of nano nitrogen in enhancing finger millet growth, increasing yield, optimizing nutrient uptake and improving nitrogen use efficiency in finger millet cultivation.

Improving upland rice (Oryza sativa l.) performance through enhanced soil fertility and water conservation methods

The experiment was conducted at Experimental sites of Tanzania Agricultural Research Institute (TARI) – Ukiriguru, Mwanza, Tanzania. The objective was to improve performance of upland rice through enhanced soil fertility and water conservation methods. A split–split plot experiment in a randomized complete block design with three replications and three factors that were (a) upland rice cultivars (WAB 450, NERICA1 and NERICA4) (b) fertilizer types, (Urea 80Kg N/ha, farm yard manure 5 t/ha and control) (c) three water conservation methods (flat cultivation, open ridge and tie ridge were applied). Rice was sown in seven rows at 30 cm inter–and intra–row spacing. Data on soil, weather, crop growth, yield components and grain yield were collected. Rainfall was 651.2 mm during the cropping season which was poorly distributed. Average temperature was 24oC with mean relative humidity of 75%. Soil analysis results showed that total nitrogen was 0.08 %, phosphorus 2.09mgP/Kg and organic carbon 0.58%. The soil calcium was 3.38 cmolc/Kg and potassium was 0.36cmolc/Kg, while zinc was 0.39 mg/Kg. Cultivars had significant effect on yields which were 2856, 2507 and 2140 Kg/ha for WAB 450, NERICA4 and NERICA1 respectively. Fertilizer types also significantly affected grain yield in the order of urea (3368 Kg/ha) > FYM (2723 Kg/ha) and > control (1421 Kg/ha). Moisture conservation methods significantly affected yield in this order: tie ridges (2710 Kg/ha) > open ridge (2398 Kg/ha) > flat cultivation (2394 Kg/ha). Overall, the study results indicated low fertility status in the soil, although it was found to be suitable for upland rice production with further improvement. It is concluded that rice cultivar, WAB 450 had the highest yield potential, while application of Urea at 80 Kg N/ha gave high grain yield, while tie ridges were the best in soil moisture conservation.

Enhancing the use of coated urea fertilizer and assessing its effect on growth and yield performance in grain corn

Use of urea fertilizer is currently increasing to meet the agricultural demand. However, the efficiency and optimization of urea application in agriculture is uncertain. Therefore, this study was conducted to compare the efficacy of slow-release urea and standard urea fertilizer. Reductions in the N rate of the slow release was assessed by measuring the different growth performance and yield at the field. A 25% reduction in N content using coated urea gave similar growth performance and yield compared to standard practice The findings indicated that there was no significant difference in stem diameter, number of leaves and chlorophyll content between the control treatment and slow-release urea. Grain yield and yield components like cob length, number of grains per cob, weight of grain per cob and 1000 grain weight obtained in the field was similar when applying the slow-release urea with the yield and yield components obtained from standard practice as a control. We conclude that this slow-release urea can be used in extensive cropping of corn while promising at least the same yields than standard practices with reducing impact on environment and nitrogen losses in the soil.

Blended controlled-release nitrogen fertilizer increases rice post-anthesis nitrogen accumulation, translocation and nitrogen-use efficiency.

One-time application of blended controlled-release nitrogen fertilizer (CRN) has the potential to solve the difficulty of top-dressing fertilizer in the cultivation of rice and reduce the cost of CRN fertilizer application. However, its effects on rice dry matter and nitrogen (N) accumulation and translocation, yield and N-use efficiency (NUE) remain uncertain. Field experiments were carried out at three sites (Mingguang, Chaohu, and Guichi) in the Yangtze River Delta in China to compare the effects of the conventional split applications of urea and the blended CRN and on post-anthesis dry matter and N accumulation and translocation, yield, and NUE in rice at 0, 60, 120, 180, and 240kg N ha-1. The results showed that at the equal N application rates, compared under the conventional N fertilizer treatment, the blended CRN application significantly increased the rice yield by an average of 0.9-6.9%, mainly due to increase the number of spikelets per panicle. The highest yield achieved with blended CRN treatment occurred at 200kg N ha-1, with an NUE of 45.9%. Moreover, in comparison to the conventional N fertilizer, the blended CRN treatment increased pre-anthesis N translocation (Pre-NT) by 1.0-19.8%, and the contribution of pre-NT to grain N by 0.2-8.7%, and NUE by 3.2-28.4%. Meanwhile, the blended CRN treatment reduced labor costs by 1800 Yuan ha-1 and enhanced the economic gains by 21.5-68.8%. Therefore, one-time application of blended CRN ≤ 200kg N ha-1 application rate improved rice yield, NUE, and economic profit compared to equivalent rates of split applied conventional N fertilizers.

Response of spring rice (Oryza sativa L.) varieties to different nitrogen application methods at Nawalparasi West, Nepal

Rice (Oryza sativa L.) cultivation necessitates an adequate supply of nitrogen to achieve optimal growth and yield. This study, conducted in Nawalparasi West from February to June 2023, aimed to assess the effects of nitrogen management through a foliar spray of nano urea, compared to need-based nitrogen management using the Leaf Color Chart (LCC) and the Recommended Dose of urea Fertilizer (RDF) application. The experiment followed a Randomized Complete Block Design (RCBD) with three replications, incorporating four nitrogen management levels (Control, RDF through urea fertilizer (120 kg/ha), 25% of RDF through basal urea (30 kg/ha) + nano urea, and 25% of RDF through basal urea (30 kg/ha) + (LCC) and two rice varieties (Chaite-5 and Hardinath-1). The results indicated that the LCC-based treatment produced the highest grain yield at 5.18 mt/ha, statistically similar to the yield of the nano urea-based treatment (5.04 mt/ha). The enhanced yields were attributed to more effective tillers per m² (260.17 tillers/m² and 253.17 tillers/m², respectively), longer panicle length (28.12 cm and 25.99 cm), more filled grains per panicle (210.03 and 215.73), and lower sterility percentage (24.93% and 26.95%). Despite comparable yields, nano urea application proved to be more cost-effective [97,926.10 Nepalese Rupees (NRs)] with a higher benefit-cost ratio (1.78) and greater ease of application for farmers compared to the LCC. Varietal responses varied, with Hardinath-1 exhibiting the highest yield with LCC-based nitrogen application (5.37 mt/ha), and Chaite-5 demonstrating the highest yield (4.778 mt/ha); with nano urea-based nitrogen application (5.31 mt/ha). Chaite-5 displayed a greater effective number of tillers per m² (241.42 tillers/m²) and filled grains per panicle (224.56). Consequently, it is suggested that nano urea-based nitrogen application, particularly in conjunction with a variety of Chaite-5, holds the potential for improved productivity.

Evaluating machine learning models and identifying key factors influencing spatial maize yield predictions in data intensive farm management

Understanding the relationships between crop yields, soil properties, weather patterns and input applications is important for optimizing agricultural production. Data variation analysis using statistical and machine learning (ML) approaches can help identify and understand the practices that optimize yield. The objectives of this study were (i) to evaluate the predictive accuracy of selected ML models for estimating grain yields in on-farm maize (Zea mays L.) trials with different combinations of seeding and fertilizer rates in a commercial field, and (ii) to investigate the ability of ML models to assist in identifying yield-limiting factors in the same field. Multiple linear regression, multilayer perceptron, decision tree, and random forest (RF) ML models were trained and tested using crop management and soil from a data-intensive farm management (DIFM) trial and remotely sensed data. The dataset consisted of multiple subplot treatment observations of crop management, soil properties and normalized difference vegetation index (NDVI), linked to final grain yield for the 2019/2020 and 2020/2021 seasons. The RF had the best combination of high correlation (R2 = 0.69 and 0.80) and low error (MAPE = 5.4 and 8.4% and RMSE = 0.69 and 0.95 t ha−1) when compared to other models for both seasons. Feature importance analysis revealed that urea application was consistently the most critical variable and explained yield variations to the greatest extent, whereas soil phosphorus (P), plant population, and sodium in 2020, and soil P, soil pH, clay content, and plant population in 2021 emerged as the most influential factors for explaining yields. This study concluded that the RF model was the best for spatial yield predictions using DIFM trial datasets. There was also variability between seasons in yield limiting factors resulting from temporal variations in growing conditions. To effectively apply insights from yield prediction models, it is crucial that the variables incorporated into these models have a significant connection to yield and the findings can be translated into actionable management decisions. The DIFM trials combined with ML can play an important role in advancing the field of precision agriculture by providing valuable insights into the complex interactions between crops, soils, and management practices, and identifying new opportunities for improving crop yields and environmental sustainability.

Fertilizer application alters cadmium and selenium bioavailability in soil-rice system with high geological background levels

The co-occurrence of cadmium (Cd) pollution and selenium (Se) deficiency commonly exists in global soils, especially in China. As a result, there is great interest in developing practical agronomic strategies to simultaneously achieve Cd remediation and Se mobilization in paddy soils, thereby enhancing food quality/safety. To this end, we conducted a field-plot trial on soils having high geological background levels of Cd (0.67 mg kg−1) and Se (0.50 mg kg−1). We explored 12 contrasting fertilizers (urea, potassium sulfate (K2SO4), calcium-magnesium-phosphate (CMP)), amendments (manure and biochar) and their combinations on Cd/Se bioavailability. Soil pH, total organic carbon (TOC), soil available Cd/Se, Cd/Se fractions and Cd/Se accumulation in different rice components were determined. No significant differences existed in mean grain yield among treatments. Results showed that application of urea and K2SO4 decreased soil pH, whereas the CMP fertilizer and biochar treatments increased soil pH. There were no significant changes in TOC concentrations. Three treatments (CMP, manure, biochar) significantly decreased soil available Cd, whereas no treatment affected soil available Se at the maturity stage. Four treatments (CMP, manure, biochar and manure＋urea＋CMP＋K2SO4) achieved our dual goal of Cd reduction and Se enrichment in rice grain. Structural equation modeling (SEM) demonstrated that soil available Cd and root Cd were negatively affected by pH and organic matter (OM), whereas soil available Se was positively affected by pH. Moreover, redundancy analysis (RDA) showed strong positive correlations between soil available Cd, exchangeable Cd and reducible Cd with grain Cd concentration, as well as between pH and soil available Se with grain Se concentration. Further, there was a strong negative correlation between residual Cd/Se (non-available fraction) and grain Cd/Se concentrations. Overall, this study identified the primary factors affecting Cd/Se bioavailability, thereby providing new guidance for achieving safe production of Se-enriched rice through fertilizer/amendment management of Cd-enriched soils.

Comparative Evaluation of Nano Urea and Urea Foliar Sprays on Nutrient Uptake and Soil Fertility in Fodder Maize (Zea mays L.) Production

An investigation on “Comparative Evaluation of Nano Urea and Urea Foliar Sprays on Nutrient Uptake and Soil Fertility in Fodder Maize (Zea mays L.) Production” was conducted during kharif 2022 at ZARS, V. C. Farm, Mandya, on sandy loam soil. The experiment was laid out in RCBD with eleven treatments replicated thrice. Treatments include combinations of basal application of urea at 50, 75 and 100% recommended dose of N with varied levels of nano urea and urea spray at 20 and 40 DAS, which were compared with RDF and control (RDF without N). Among the treatments tested, 100% recommended dose of N + Urea @ 2% spray recorded significantly higher green fodder yield (427.70 q ha-1) and dry matter yield (91.64 q ha-1), nutrient uptake (153.49 kg ha-1 of N, 33.37 kg ha-1of P and 121.29 kg ha-1 of K) and was on par with 100% recommended dose of N + Nano urea @ 0.4% spray. Available N, P2O5 and K2O status in the post-harvest soil varied significantly but pH, EC and OC was not significantly influenced by varied levels of recommended dose of nitrogen with different foliar concentrations of nano urea and urea. Higher soil available nitrogen, phosphorus and potassium was recorded 100% recommended dose of N + Urea @ 2% spray (213.25, 42.58, 189.06 kg ha-1, respectively) followed by 100% recommended dose of N + Nano urea @ 0.4% spray (200.70, 40.87 and 187.95 kg ha-1, respectively).

Transforming waste cellulosic fabric dyed with Reactive Yellow C4GL into value textile by a microwave assisted energy efficient system of color stripping

A million ton of cotton fabric is wasted during cutting process in garment industry as well as in textile dyeing industry due to faulty dyeing. Color stripping of cotton fabric has become a significant challenge in the textile industry because the harsh chemicals used in chemical stripping processes affects the quality of fabric very badly. Conventional stripping methods lead with severe effects due to prolonged treatment time and high chemical concentrations. Recently, microwave-assisted stripping techniques have been emerged as effective alternatives to improve stripping efficiency. In this research, the developed microwave assisted stripping system is improved by the application of Urea, which is utilized as a microwave absorber to further reduce stripping time, temperature, and chemical concentration kept focus on quality parameters of recycled cotton fabric. This study inspects the efficiency of microwave absorber-assisted alkali hydrolysis and reduction in terms of dye-fabric bond cleavage, chromophores removal, chemical consumption, and processing time and compared with sequential stripping, microwave assisted stripping without absorber and conventional methods. The results indicated that microwave absorber-assisted alkali hydrolysis and reduction achieved 90 % stripping efficiency by using lowest concentrations of chemicals, while sequential stripping yielded a stripping efficiency of 96 %. Similarly, microwave absorber assisted methods resulted in minor loss in tear strength and weight. These outputs highlight the superior performance of microwave absorber-assisted techniques, demonstrating their efficiency, novelty, time-saving nature, and reduced damage compared to other methods.

Improvement in Physiochemical Characteristics of ‘Prime Seedless’ Grapes by Basal Defoliation with Foliar-Sprayed Low-Biuret Urea and Cyanocobalamin under Mediterranean Climate

In viticulture, the main target is to achieve high yield and good fruit quality without compromising vine growth. Methods to achieve this balance will vary with regard to climate and cultivar. A two-year study was conducted on five-year-old ‘Prime Seedless’ grapevines to evaluate the effect of leaf defoliation and the foliar application of low-biuret urea (LBU) and cyanocobalamin (CCA) on berry set percentage, the compactness coefficient of the clusters and the overall quality of clusters and berries. The removal of the first four basal leaves was conducted at the full-bloom (FB) stage, while LBU (5 g·L−1) and CCA (40 mg·L−1) were sprayed at three phenological stages: (1) when the cluster length reached ~10 cm long, (2) at FB and (3) one week after the fruit set. The results demonstrated that the sole application of basal leaf removal (BLR) or in combination with LBU and/or CCA improved the vegetative growth, total yield and physiochemical characteristics of clusters and berries, whereas the same treatments decreased berry set and shot berry percentages and the compactness coefficient of the clusters, which in turn led to looser clusters compared to the control. The most pronounced effect was recorded for the combined application of BLR, LBU and CCA, which revealed the highest values of shoot length, leaf area and the contents of chlorophyll, proline, N, P, K, Ca, Mg, Fe and Zn. The same treatment recorded the lowest berry set and shot berry percentages, compactness coefficient of clusters and decay percentage. Overall, this treatment was the best in terms of total yield, cluster weight, berry firmness, soluble solid content (SSC), the SSC/acid ratio, total sugars, total carotenoids, total phenols, phenylalanine ammonialyase and polyphenol oxidase.

Urea promoted soil microbial community and reduced the residual ciprofloxacin in soil and its uptake by Chinese flowering cabbage.

Antibiotics in agricultural soil can be accumulated in crops and might pose a potential risk to human health. Nevertheless, there is a lack of knowledge about the impact of nitrogen fertilizers on the dissipation and uptake of antibiotics in soils. Therefore, our aim in this study is to investigate the effects of urea fertilizer on the residues of ciprofloxacin and its uptake by Chinese flowering cabbage (Brassica parachinensis L.) as affected by the associated changes on the soil microbial community. A pot experiment has been conducted using spiked soil with 20 mg ciprofloxacin /kg soil and fertilized with urea at dosages equal to 0, 0.2, 0.4, 0.8 t/ha. Application urea especially at 0.4 t/ha decreased the residue of ciprofloxacin in the soil and its uptake by the roots and its translocation to the shoots of Chinese flowering cabbage. The translocation factors (TFs) for ciprofloxacin were significantly decreased (P < 0.05) only at the treatment of 0.4 t/ha, while no significant difference of bio-concentration factors (BCFs). The average well color development (AWCD) values, Shannon diversity, and richness index were higher in the fertilized than the un-fertilized soils, and all such indicators were greater at the treatment of 0.4 t/ha than at 0.2 and 0.8 t/ha. The carbon substrate utilization of phenolic acids at the treatments of 0.4 t/ha were greater than with other levels of urea fertilizer. In conclusion, moderate urea addition significantly increased soil microbial activity and abundance, which in turn promoted the ciprofloxacin dissipation in soil and plant tissue. The present study provides an economical and operational strategy for the remediation of ciprofloxacin contaminated soils.

One-Time Contact Application of Controlled-Release Urea and Optimized Method Improved Rice Yield and Nitrogen Use Efficiency with 50% Nitrogen Input

Excessive nitrogen application is a common phenomenon in rice production in China, which will lead to a low nitrogen utilization rate and increase farmers’ production costs. In Jingzhou, Hubei Province, for two consecutive years (2021, 2022), rice was planted with nursery-box total fertilization (NBTF) technology to provide technical support for rice seedling box contact fertilization technology. The results showed that, compared with the conventional treatment, the seedling emergence rate decreased by 7.70–11.87%, but the seedling quality significantly improved and the plant height significantly increased by 4.38–6.06% in the full-heading stage after the aforementioned treatments. The leaf area index significantly increased by 16.75–34.55%, 10.04–19.30%, and 12.13–18.60% in the tiller, booting, and full-heading stages, respectively, whereas the photosynthetic rate significantly increased by 3.80–5.25% in the booting stage. The rice yield under the 50% CRU and 50% CRU + S treatments was the same as that under the FFP treatment. The rice yield under 50% CRU + BT and 50% CRU + BT + S treatments was 7.50–10.61% higher than that under the FFP treatment; nitrogen partial factor productivity increased by 96.15–123.63%. NBTF combined with Boxingtanzhuang (in Chinese) seedling trays showed an increase in yield, whereas normal seedling trays showed a stable yield. It is suggested that the seedling tray and fertilizer should be specialized in the rice seedling box, and the height of the seedling tray should be increased by 3–5 cm. At the same time, special controlled-release urea should be selected to ensure less N release before emergence and improve the seedling emergence rate so as to popularize NBTF technology in a large area.