Maharana Pratap University of Agriculture and Technology

Antimicrobial resistance (AMR) has emerged as a major global challenge in aquaculture, largely driven by the widespread and frequently unregulated use of antibiotics in finfish, shrimp, and shellfish production systems. Intensive farming practices characterized by high stocking densities, suboptimal biosecurity, and limited disease diagnostics increase infection pressure and encourage prophylactic and metaphylactic antimicrobial use. Consequently, antibiotic residues accumulate in water, sediments, and aquatic organisms, imposing strong selective pressure that promotes the emergence and persistence of antimicrobial-resistant bacteria and accelerates the horizontal transfer of antimicrobial resistance genes (ARGs) within aquatic ecosystems through horizontal gene transfer (HGT) mechanisms such as conjugation, transformation, and transduction. Increasing evidence indicates that aquaculture systems function as critical hotspots for AMR development, facilitating the dissemination of resistant pathogens and ARGs to wild aquatic biota, terrestrial environments, livestock systems, and humans through direct exposure, environmental pathways, and the consumption of aquaculture products. This review synthesizes current knowledge on regional patterns of antimicrobial use in aquaculture. It examines the molecular and ecological mechanisms driving antimicrobial resistance, including antibiotic persistence in water and sediments and the resulting selection pressure on microbial communities. The review also highlights the spread of ARGs through HGT, which contributes to the emergence and dissemination of resistance. Furthermore, it discusses the environmental and public health implications of AMR, particularly the transmission of resistant bacteria and ARGs through aquatic environments and seafood. These pathways may increase the risk of human infections and reduce the effectiveness of antibiotic treatments. It further examines the prevalence and diversity of antimicrobial-resistant pathogens in cultured finfish, shellfish, and ornamental species, identifying integrated farming systems as key amplifiers of resistance dissemination. Finally, the review highlights critical gaps in surveillance and governance and emphasizes the urgent need for strengthened regulatory frameworks, comprehensive AMR monitoring, and the adoption of sustainable disease management alternatives, including vaccination, probiotics, immunostimulants, bacteriophage therapy, and phytotherapeutics. Advancing One Health–oriented strategies is essential to mitigate AMR risks, safeguard aquatic animal health, preserve environmental integrity, and ensure global food safety.

Climate change and associated environmental stresses increasingly threaten crop productivity by intensifying pathogen and pest pressure. Plants respond to these challenges through sophisticated defense mechanisms in which secondary metabolites play a central role. Plant secondary metabolites (PSMs) contribute to resistance against biotic stress by inhibiting pathogen growth, deterring herbivores, and modulating defense signaling pathways. Their accumulation and activity are regulated through transcriptional and metabolic reprogramming following pathogen perception. Recent studies have demonstrated that the defensive functions of major PSM classes, including phenolics, terpenoids, and alkaloids, are controlled by complex regulatory networks involving transcription factors, phytohormonal crosstalk, and synergistic metabolite interactions. Advances in metabolomics, transcriptomics, and genome-editing technologies have enhanced understanding of the biosynthetic regulation, spatial-temporal dynamics, and coordinated deployment of PSMs during plant-pathogen interactions. These insights highlight the integration of metabolic pathways with immune signaling processes. Transcription factors function as key regulators integrating stress perception with metabolic and defense responses, thereby modulating growth-defense trade-offs under biotic stress. Despite extensive characterization of PSM, the molecular mechanisms underlying their interactions with pathogens and their roles in resistance activation remain incompletely understood. In view of the environmental limitations of chemical pesticides, plant-derived metabolites offer a promising basis for sustainable disease management. This review synthesizes recent advances in the regulation and function of secondary metabolites in plant immunity, highlighting key knowledge gaps and opportunities for their application in environmentally sound plant protection strategies.

Black turmeric (Curcuma caesia Roxb.) is an endangered perennial herb of the Zingiberaceae family. It is widely recognized for its rich phytochemical profile and therapeutic uses. Despite its significance, this crop is underexplored due to limited genomic research. To address this, we assessed the genetic variation and population structure of 54 black turmeric accessions collected from 16 districts of central India covering six agro-climatic zones using SCoT marker system. Out of 36 markers screened, 20 markers showed polymorphic and reproducible bands. These primers amplified 179 distinct fragments (150 –1300 bp; average 8.8 bands per primer) and revealed a high polymorphism rate (avg. 91.13

This study investigates the effect of seed priming with zinc bionanocrystals on germination and early seedling vigor in Pennisetum glaucum (pearl millet). Zn-bionanocrystals were synthesized using the ionotropic gelation method, yielding particles with a size of 374–396 nm, a zeta potential of + 39.7 to + 44.6 mV, and an encapsulation efficiency of 84

Abstract The growing pressure on soil resources from climate change, land degradation, and the increasing demand for food security has intensified the need for rapid, accurate, and cost-effective methods of soil characterisation. Diffuse reflectance spectroscopy (DRS), operating across the visible-near infrared (Vis-NIR: 350–2500 nm) and mid-infrared (MIR: 4000–400 cm⁻¹) regions of the electromagnetic spectrum, has emerged as a powerful analytical platform that addresses these challenges. By exploiting the diagnostic absorption features arising from molecular vibrations and electronic transitions of key soil chromophores (organic matter, clay minerals, iron oxides, calcium carbonates, and water), DRS enables the simultaneous estimation of numerous soil properties from a single spectral scan, without generating chemical waste and with minimal sample preparation. This review synthesises more than nine decades of scientific progress in soil spectroscopy, from the early spectral libraries of the 1930s to the contemporary integration of machine-learning and deep-learning frameworks. We examine the mechanisms underlying spectral absorption, critically assess the comparative performance of Vis-NIR and MIR techniques, evaluate pre-processing strategies from Savitzky-Golay smoothing and standard normal variate correction to derivative transformations, and benchmark the full spectrum of prediction models, from partial least squares regression (PLSR) and multivariate adaptive regression splines (MARS) to support vector regression (SVR), random forests, and convolutional neural networks. The review also critically documents performance across a comprehensive range of soil properties including texture, organic carbon, cation exchange capacity, pH, electrical conductivity, and macro- and micronutrients, highlighting consistent achievements as well as persistent limitations. A central argument of this review is that while the field has achieved remarkable predictive capabilities for certain core properties, key assumptions regarding model transferability, chromophore linearity, and pre-processing universality remain empirically untested. The paper concludes by identifying the five most consequential unanswered research questions in the discipline, with particular attention to the challenges posed by the heterogeneous agro-ecological landscapes of India. Recommendations for a methodologically rigorous path forward are provided. To make the comparison more transparent, selected validation results are aggregated by fertility property rather than pooled across incompatible studies. The comparison supports selective use of DRS for clay or texture, organic matter, cation-exchange capacity, and total nitrogen, while electrical conductivity, available phosphorus, potassium, and DTPA-extractable micronutrients remain dependent on the calibration domain and validation design.