For saving the expenses and time involved in the routine soil testing, a novel multi-nutrient soil extractant (OM-MES-VERA) comprising 0.0025 M EDTA +0.01 M oxalic acid +0.02 M acetic acid +0.02 M maleic acid +0.02 M 2-(N-Morpholino) ethane sulfonic acid (MES) + 0.1% polyacrylamide with final pH (6.0) has been developed. This extractant was used to assess the availability of macronutrients from soil and compared with the conventional soil test methods. In a laboratory evaluation with diverse soils (n = 32), OM-MES-VERA extracted K similar to 1 M ammonium acetate (pH 7.0) but extracted significantly lower amounts of inorganic N (NH4 + + NO3 -), P, S, Ca and Mg compared to conventional alkaline KMnO4 hydrolysable N, Olsen's- or Bray's- P, 0.15% CaCl2 extractable S, 1 M ammonium acetate extractable Ca and Mg, respectively. Interestingly, the absorbance ratio (OD465/OD665) of OM-MES-VERA extracts significantly correlated with the conventional alkaline KMnO4 hydrolysable N (R2-value = 0.386, Significant at p <= .01) and additional inclusion of clay and organic C contents, pH and electrical conductivity led to an improved prediction of N (R2-value = 0.501, significant at p <= .01). Other macronutrients (P, K, S, Ca, Mg) extracted by OM-MES-VERA could be successfully regressed on the conventional soil test values (R2-value 0.342-0.633, all significant at p <= .01). The soil test values by OM-MES-VRA and conventional methods were correlated with soil properties. Further greenhouse and field studies are required to prove the suitability of OM-MES-VERA extractant for assessing the availability macronutrients.
Phosphorus (P) management is a key aspect of sustainable agriculture. However, its effectiveness also depends on the phosphate source. We investigated whether phosphate sources contribute to soil P availability, grain yield (GY), and P uptake by chickpea, wheat, and soybean cropping sequences. We conducted a pot experiment under controlled conditions, with six commercial phosphate sources, a rate of 150 mg P kg-1 of soil, one control, and four replications. Triple superphosphate (TSP) increased the GY by 25.6%, whereas the lowest yields, -20.9 and -18.4%, were recorded from the Alvorada and Gafsa phosphates, respectively, for chickpea. With respect to the residual effect, only Bay & oacute;var increased the wheat GY by 20.5%; in contrast, compared with the control, the residual effect of all the phosphate sources applied increased the soybean GY, compared to the control. However, the variation in the P concentration in plant tissues was influenced by the phosphate source and P use efficiency (PUE). Additionally, phosphate sources increased soil P availability, depending on the phosphate source, soil pH, and extractant used. Finally, Olsen P and Mehlich-3 were significantly correlated with the GY and P concentrations in the plants. Under low-P conditions, plants increased their root growth to mine P and PUE and sustain development and yield. More soluble phosphate sources, such as TSP, are better for immediate crop response, whereas phosphates with less solubility contribute more to long-term soil P availability. However, the limitation of some current methods for accurately reflecting the true P status of the soil can be a challenge.
This study developed an innovative fertilization framework integrating nano-urea with diverse organic amendments to enhance nutrient efficiency, salinity tolerance, and productivity in tomato (Solanum lycopersicum L. cv. Pusa Sheetal). Conducted over two years (2021-23) in Noida, India, the research employed a randomized block design to compare various combinations of nano-urea foliar sprays (2% and 4% w/v) and organic amendments, including farmyard manure, vermicompost, organic cakes, under both normal and saline (EC 4 dS m(-1)) conditions. Results demonstrated that replacing conventional nitrogen doses with integrated nano-urea and organic treatments significantly improved soil health by increasing soil organic carbon (up to 37%), macronutrient availability (N, P, K) while reducing electrical conductivity (up to 24.4%) in saline soils. Morphologically, the synergy between nano-urea and organic matter mitigated salt stress, resulting in substantial increases in plant height (21-25%), branching (13-26%), leaf production (13-24%), fruit number (20-53%), fruit weight (23-30%), and overall yield (44-89%) compared to control and saline-only treatments. Biochemically, the integrated approach upregulated the plant's antioxidant defense system, showing significant increases in ascorbate peroxidase (34-74%) and superoxide dismutase (35-68%) activity. Concomitantly, a reduction in reactive oxygen species (ROS), hydrogen peroxide, and malondialdehyde (MDA) levels indicated a mitigation of salinity-induced oxidative damage. In addition, fruit quality was enhanced through elevated levels of carotenoids, lycopene, and vitamin C. Overall, the findings reveal a synergistic nutrient-delivery framework where nano-enabled nitrogen, coupled with organic amendments, optimizes rhizosphere chemistry and reinforces the ascorbate-glutathione cycle. This integrated approach represents a scalable, cost-effective advancement in precision nutrient management for sustainable tomato production in stress-prone agroecosystems.
With rising populations, boosting agricultural productivity is essential. Although chemical fertilizers are common, excessive use increases costs and harms the environment. Zeolite offers an alternative due to its porous structure and cation exchange capacity. In this study, ammonium nitrate was loaded into natural zeolite from Manisa/T & uuml;rkiye, and the nitrogen content of the fertilizer was 5.80%. Raw zeolite and zeolite-based fertilizer samples were characterized using Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The zeolite-based fertilizer was tested on lettuce (Lactuca sativa L) plants in a greenhouse experiment and its usability as a fertilizer and its effect on yield were investigated. According to the results obtained, while the length, leaf number, head diameter, and head weight data of the ZN25 (187.5 ppm Nitrogen) group containing zeolite-based fertilizer were measured as 31.28 cm, 28.88, 16.83 cm and 135.10 g, respectively, for the pure ammonium nitrate applied group (N50; 375 ppm Nitrogen), the related parameters were measured as 29.53 cm, 26, 12.87 cm and 106.80 g, respectively, and it is clear that ZN25 provided better efficiency than N50. Additionally, because of the greenhouse experiment, it was observed that there was a correlation between nitrogen and chlorophyll contents in the application groups. The nitrogen and chlorophyll contents of the ZN25 and N50 groups were measured as 4.29%, 38.14 soil plant analysis development (SPAD) and 5.97%, 43.38 SPAD, respectively. According to these results obtained, zeolite-based fertilizer increased crop yield by using less nitrogen and has the potential to be used in agriculture.
