Indian Institute of Soil Science,Indian Council of Agricultural Research

Arsenic (As) transfer from contaminated soils to food grains is a major pathway of As entry into humans in paddy growing areas posing a serious risk to human health. This study investigates the effectiveness of irrigation water management combined with phosphate (P) and vermicompost applications, in immobilizing As and blocking its entry to rice grain. Different doses (0, 30 and 60 mg kg–1) of P, vermicompost (C), (0, 2.5 and 5.0 g kg–1) were applied under W1 (submerged) and W2 (alternate wetting and drying, AWD). Total and bioavailable As in soil were 33.8 mg kg–1 and 3.41 mg kg–1, respectively. Under different treatment combinations, As in soil was highest in amorphous hydrous oxides of Fe and Al (F3) fraction whereas least in non-specifically sorbed (F1) fraction. Arsenic content in rice grain decreased from 0.38 (P1-0 mg kg–1) to 0.25 mg kg–1 (P3-60 mg kg–1), whereas in case of vermicompost application the grain As decreased from 0.32 (C1-0 g kg–1) to 0.27 mg kg–1 (C3-5.0 g kg–1). The lowest grain As content was observed under the W2 condition with the combined application of P (P2-30 mg kg–1) and vermicompost (C2-2.5 g kg–1). Both grain and straw As were positively correlated with As associated with F1 and F2 soil fractions, whereas both showed negative correlation with As in F3, dithionite citrate bicarbonate-As, and oxalate-extractable Fe. Overall, the combined application of P (at 30 mg kg–1) and vermicompost (at 2.5 g kg–1) effectively reduced grain As content under W2. These findings suggest that combining AWD with P and vermicompost application can be a viable approach for reducing As toxicity in rice cultivation; however, field-scale validation across different soils and cultivars is required before broader recommendations can be made. Based on the graphical abstract, this study evaluates the effectiveness of irrigation water management combined with phosphate (P) and vermicompost (C) applications in immobilizing arsenic (As) and limiting its transfer to rice grains. Different doses of P and vermicompost were applied under two irrigation regimes: W1 (continuous submergence) and W2 (alternate wetting and drying, AWD). The total and bioavailable As contents in soil were 33.8 mg kg⁻¹ and 3.41 mg kg⁻¹, respectively. Across all treatment combinations, the highest proportion of soil As was associated with the amorphous hydrous oxides of Fe and Al (F3), while the lowest was found in the non-specifically sorbed (F1) fraction. Under W1 conditions, As distribution was higher in labile fractions (F1 = 0.52

Modified biochar based remediation has emerged as a promising strategy for addressing potentially toxic elements (PTE) in soils, owing to its diverse physicochemical properties and environmental compatibility. Most prior reviews focus on pristine biochar for wastewater treatment, overlooking the enhanced potential of modified biochars in soil based PTE remediation. This review establishes a clear linkage between the pristine biochar modification methods to surface chemistry changes and novel immobilization mechanisms, while also evaluating field applicability and long-term risks. A bibliometric analysis of 1170 publications from 2010 to 2024 was conducted to map international collaborations, thematic evolution, and knowledge hotspots. Results showed that research themes clustered around bioremediation processes, metal adsorption/immobilization mechanisms, and biochar based pollution control. The analysis revealed a shift from foundational studies to application-driven research, with a surge in interest toward modified biochars and complex contaminant interactions after 2021. Biochar production parameters and post-synthesis modifications critically shape its functional properties, which in turn govern key immobilization mechanisms. However, field efficacy of modified biochar is influenced by environmental factors. Additionally, aging processes and potential metal remobilization pose long-term sustainability concerns. Modified biochars offer a context-dependent but promising tool for sustainable soil remediation, contingent on addressing their environmental trade-offs and implementation challenges.

A comprehensive three-year field study was conducted to develop and validate soil test crop response (STCR)-based nutrient prescription equations for coriander (Coriandrum sativum L.) in Alfisols. The research comprised three distinct experimental phases: a fertility gradient experiment, a main experiment, and a validation trial. Across these phases, over 72 soil and plant samples were collected and analyzed for nutrient content and compositional quality. The fertility gradient experiment established significant variability in soil NPK status using fodder maize as an indicator crop. In the main experiment, coriander plots subjected to varying fertility levels and nutrient management strategies-including farmyard manure (FYM) supplementation-were assessed for yield, nutrient uptake, and key quality metrics (total phenols, flavonoids, and ascorbic acid). Prescription equations targeting specific yield levels were developed by calculating nutrient requirements and quantifying contributions from soil, fertilizer, and FYM. The validation trial demonstrated that STCR-based recommendations, especially those integrating 7.5 t ha ⁻ ¹ FYM, substantially improved green foliage yield (up to 56.9% higher), nutrient uptake (N, P, K), and quality parameters compared to generalized recommended doses and soil fertility rating approaches. Enhanced outcomes were observed for value cost ratio, response yield stick, and nutrient use efficiency indices (Partial Factor Productivity, Agronomic Efficiency, Partial Nutrient Balance, Internal Utilization Efficiency). Overall, the STCR approach with integrated nutrient management proved effective in increasing yield, improving quality, and optimizing nutrient use efficiency in coriander, advancing the case for site-specific and balanced fertilizer application in sustainable coriander production.

The war against Iran is the continuation of the June 2025 12-day bombings in which Israel and the United States destroyed much of Iran's nuclear assets and air defences. The outcome was strategically inconclusive. The diplomacy that followed was futile: Iran would not offer the nuclear capitulation the US demanded, and Israel was eager to strike. Iran's system has proven more resilient and tolerant of pain than the Trump administration expected. Although supreme leader Ayatollah Ali Khamenei was killed, his son Mojtaba was expeditiously chosen to replace him. Iran is undeniably weakened and cannot re-emerge as a conventional power in the next decade. But the war has validated the Gulf Arab states' concerns about their exposure, the United States' capacity to defend them, the risks of protracted instability and the perils of an unconstrained Israel. The Middle East must now contain a weakened, militarised, angry Iranian regime willing to disrupt regional geo-economic and geopolitical relationships.

The long-term effect of partially substituting chemical fertilizers by organic inputs on soil quality and yield of pearl-millet and wheat under semi-arid region of Indo-Gangetic plains of India is unclear. This decadal field experiment (2009-2019) evaluated the impact of partial substitution of chemical fertilizers through organic inputs on soil carbon, microbial dynamics, soil quality and yield of pearl millet-wheat system. The experiment was laid out under randomized block design (RBD) with seven treatments and three replications in ten consecutive cropping cycles from 2009 to 2019. The seven treatments were: Ck- no chemical fertilizer, FYM-farm yard manure @15 Mg ha(-1), RDF- recommended dose of N and P, STCR-I- chemical fertilizer for achieving 3.0 and 5.5 Mg ha(-1) targeted yield of pearl millet and wheat, respectively, STCR-II- chemical fertilizer for achieving 3.5 and 6.0 Mg ha(-1) targeted yield of pearl millet and wheat, respectively, IPNS-I- FYM + chemical fertilizer for achieving 3.0 and 5.5 Mg ha(-1) targeted yield of pearl millet and wheat, respectively and IPNS-II-FYM + chemical fertilizer for achieving 3.5 and 6.0 Mg ha(-1) targeted yield of pearl millet and wheat, respectively. Treatment IPNS-I and IPNS-II improved nutrient supply system, and yields of pearl millet and wheat by lowering soil pH (7.78 and 7.79), soil bulk density (1.38 Mg m(3)) and enhancing soil organic carbon (0.83 and 0.85%), C-stock (17.1 and 17.6 Mg C ha(-1)) and its buildup rate (1.71 to 1.76 Mg C ha(-1) yr(-1)). Treatments FYM, IPNS-I and IPNS-II significantly (P < 0.05) enhanced microbial biomass carbon, potential activities of soil enzymes, soil nutrients and soil quality over the STCR-II, STCR-I, RDF and Ck, however, microbial (M-q) and metabolic quotient exhibited reverse trends. The highest SQI (0.795) was recorded with IPNS-I followed by IPNS-II (0.791), T-2 (0.771) and the lowest in Ck (0.341). Available P, acid phosphatase, available N and Mq were the key soil quality indicators in MDS for the pearl millet-wheat production in semi-arid zone, contributing 20.4, 21.0, 19.6 and 7.96% toward soil quality development, respectively. Treatment IPNS-I and IPNS-II not only achieved the targeted yield of pearl millet and wheat within +/- 10% yield deviation, but also increased pearl millet yields by 7.83 and 25.6%, and wheat yield by 10.4 and 23.9% over RDF, respectively due to improving SQI. As a result, SQI had significant correlation with grain and stover/straw yield of pearl millet and wheat indicated prominent influence of partial substitution of organic manure to inorganic fertilizers. Thus, our results evinced that long-term partial substitution of inorganic fertilizer based on targeted yield approach of soil test crop response (STCR) provides better environment for pearl millet-wheat productivity in semi-arid Inceptisol of India.