Mohammad Maroof Shah

Plants are continuously exposed to abiotic stresses such as drought and salinity, which severely impair growth, metabolism and crop productivity. To survive under these adverse conditions, plants have evolved highly coordinated mechanisms for stress perception, early signal transduction and downstream adaptive responses. Stress perception begins at the plasma membrane and subcellular compartments, where osmotic imbalance, ionic toxicity and membrane perturbations are sensed, leading to rapid calcium (Ca ²⁺ ) influx, reactive oxygen species (ROS) production and activation of mitogen‐activated protein kinase (MAPK) cascades. These early signalling events function as central hubs that integrate environmental cues with phytohormone signalling networks. Among phytohormones, abscisic acid (ABA) plays a pivotal role in mediating drought and salinity responses, whereas jasmonic acid (JA) and brassinosteroids (BR) fine‐tune antioxidant defences, metabolic reprogramming and growth–stress trade‐offs. The convergence of Ca ²⁺ , ROS, kinase signalling and hormonal pathways ultimately triggers large‐scale transcriptional reprogramming, activating genes involved in osmotic adjustment, ion homeostasis, antioxidant defence and cellular protection. This review comprehensively synthesizes recent advances in abiotic stress perception, signal transduction and hormone‐mediated regulation, highlighting their roles in shaping plant stress tolerance. In parallel, advances in conventional and molecular breeding approaches, including marker‐assisted selection and genomic selection, are highlighted as essential strategies for translating these mechanistic insights into the development of stress‐resilient cultivars. Additionally, an integrated multi‐scale framework is proposed, linking molecular, physiological and breeding‐level processes to provide a holistic understanding of drought and salinity stress tolerance and to guide the development of resilient crop systems. Furthermore, emerging biotechnological strategies, including CRISPR/Cas‐based genome editing, microbiome engineering and integrative systems approaches, are discussed as promising tools for developing climate‐resilient crops.

Parsley (Petroselinum crispum) is herb with many biological and medicinal benefits for humans. However, growth on zinc (Zn) and cadmium (Cd) contaminated sites might get severely affected due to over accumulation of heavy metals (HM) in different plant tissues. Antioxidants play a crucial role in minimizing the negative effects of HM. The present study investigates the effects of Zn and Cd stress on P. crispum morphological parameters, enzymatic/non-enzymatic antioxidant profiling and metal accumulation in shoot/root. Plants were exposed to different concentrations of Zn (50, 100, 150 and 200 µM) and Cd (10, 20, 40 and 80 µM) along with control (no stress), in soil-less Hoagland's solution. The results showed that Zn and Cd substantially decrease the growth parameters with increased contents of malondialdehyde (MDA), hydrogen peroxide (H₂O₂), and electrolyte leakage (EL). Non-enzymatic antioxidant activities, like total phenolic contents (TPC) and ferric reducing antioxidant power (FRAP), were induced high in leaves only upon Cd stress and contrarily decreased upon Zn stress. Total flavonoid contents (TFC) were decreased under Zn and Cd stress. Enzymatic antioxidant activities like superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) were also strongly induced upon Cd stress. At the same time, SOD and guaiacol peroxidase (GPX) activity was induced significantly upon Zn stress. Cd uptake and accumulation was notably high in roots as compared to shoots, which suggests P. crispum have a reduced ability to translocate Cd towards aboveground parts (leaves). Additionally, strong induction of antioxidants by P. crispum under Cd stress might indicate the capacity to effectively re-modulate its physiological response. However, further investigations regarding other HMs and experiments at the molecular level are still needed.

This study adopts a very effective high‐performance liquid chromatography (HPLC) technique for the quantitative determination of rosmarinic acid (RA) and PCR‐based amplification of biosynthetic key regulators in Isodon rugosus, Daphne mucronata, and Viburnum grandiflorum from the lower Himalayan regions. Rosmarinic acid is engaged in a variety of biological processes and has significant industrial significance. In this study, it was identified from crude methanolic extract using thin‐layer chromatography with a standard, and its content was quantified using HPLC without interrupting spikes using a mixture of methanol and deionized water containing acetonitrile (70:30 v/v) and acetic acid (0.1% v/v) at UV 310 nm absorption. We used RT‐PCR to identify cDNAs encoding PAL, C4H, and RAS, and Image J's semi‐quantitative analysis to quantify the expression levels of genes involved in RA production from chosen plant material. The highest levels of PAL, C4H, and RAS were detected, by band intensity, in the leaves and flowers of I. rugosus, which also exhibited a substantial quantity of RA. However, in V. grandiflorum and D. mucronata the transcript of the given genes was low. The concentration of RA ranged from 187.7 to 21.2 mg g⁻¹ for I. rugosus, 17.42 to 5.42 mg g⁻¹ for V. grandiflorum, and 15.19 mg g⁻¹ for D. mucronata. This study demonstrated that the method for quantifying RA from a crude methanolic extract was effective, indicating that I. rugosus might be used as an indigenous alternative source of RA.

Silver nanoparticles have received much attention, due to their wide range of biological applications as an alternative therapy for disease conditions utilizing the nanobiotechnology domain for synthesis. The current study was performed to examine the antioxidant, anticancer, antibacterial, and antifungal potential of biosynthesized silver nanoparticles (TpAgNPs) using plant extract. The TpAgNPs were produced by reacting the Tradescantia pallida extract and AgNO₃ solution in nine various concentration ratios subjected to bioactivities profiling. According to the current findings, plant extract comprising phenolics, flavonoids, and especially anthocyanins played a critical role in the production of TpAgNPs. UV–visible spectroscopy also validated the TpAgNP formation in the peak range of 401–441 nm. Further, the silver ion stabilization by phytochemicals, face-centered cubic structure, crystal size, and spherical morphology of TpAgNPs were analyzed by FTIR, XRD, and SEM. Among all TpAgNPs, the biosynthesized TpAgNP6 with a medium concentration ratio (5:10) and the plant extract had effective antioxidant potentials of 77.2 ± 1.0% and 45.1 ± 0.5% free radical scavenging activity, respectively. The cytotoxic activity of TpAgNP6 in comparison to plant extract for the rhabdomyosarcoma cell line was significantly the lowest with IC₅₀ values of 81.5 ± 1.9 and 90.59 ± 1.6 μg/ml and cell viability % of 24.3 ± 1.62 and 27.4 ± 1.05, respectively. The antibacterial and antifungal results of TpAgNPs revealed significant improvement in comparison to plant extract, i.e., minimum inhibition concentration (MIC) 64 μg/ml against Gram-negative Pseudomonas aeruginosa while, in the case of antifungal assay, TpAgNP6 was active against Candida parapsilosis. These TpAgNPs play a crucial role in determining the therapeutic potential of T. pallida due to their biological efficacy.

Diversifying available natural resources to cope with abrupt climatic changes and the necessity to equalize rising agricultural production with improved ability to endure environmental influence is the dire need of the day. Inherent allelic variability regarding significant economic traits featuring both enhanced productivity and environmental adaptability is one such prominent need. To address this requirement, a series of analyses were conducted in this study for exploring natural diploid wheat germplasm resources. The current study involved 98 Recombinant Inbred Lines (RILs) populations developed by crossing two diploid ‘A’ sub-genome wheat species, Triticummonococcum and Triticum boeoticum, enriched with valuable alleles controlling, in particular, biotic and abiotic stresses tolerance. Their 12 phenotypic traits were explored to reveal germplasm value. All traits exhibited vast diversity among parents and RILs via multivariate analysis. Most of the investigated traits depicted significant (p < 0.05) positive correlations enlightening spikelet per spike, total biomass, seed weight per spike, number of seeds per spike, plant height, and days to heading as considerably focused traits for improving hexaploid wheat. Principal component analysis (PCA) exhibited 61.513% of total variation with three PCs for 12 traits. Clustering of genotypes happened in three clades, and the two parents were separated into two extreme clusters, validating their enrichment of diversity. This study provided beneficial aspects of parental resources rich in diverse alleles. They can be efficiently exploited in wheat improvement programs focusing on introgression breeding and the recovery of eroded genetic factors in currently available commercial wheat cultivars to sustain calamities of environmental fluctuations.

Background: Photosynthesis is a key process in plants that is compromised by the oxygenase activity of Rubisco, which leads to the production of toxic compound phosphoglycolate that is catabolized by photorespiratory pathway. Transformation of plants with photorespiratory bypasses have been shown to reduce photorespiration and enhance plant biomass. Interestingly, engineering of a single gene from such photorespiratory bypasses has also improved photosynthesis and plant productivity. Although single gene transformations may not completely reduce photorespiration, increases in plant biomass accumulation have still been observed indicating an alternative role in regulating different metabolic processes. Therefore, the current study was aimed at evaluating the underlying mechanism (s) associated with the effects of introducing a single cyanobacterial glycolate decarboxylation pathway gene on photosynthesis and plant performance. Methods: Transgenic Arabidopsis thaliana plants (GD, HD, OX) expressing independently cyanobacterial decarboxylation pathway genes i.e., glycolate dehydrogenase, hydroxyacid dehydrogenase, and oxalate decarboxylase, respectively, were utilized. Photosynthetic, fluorescence related, and growth parameters were analyzed. Additionally, transcriptomic analysis of GD transgenic plants was also performed. Results: The GD plants exhibited a significant increase (16%) in net photosynthesis rate while both HD and OX plants showed a non-significant (11%) increase as compared to wild type plants (WT). The stomatal conductance was significantly higher (24%) in GD and HD plants than the WT plants. The quantum efficiencies of photosystem II, carbon dioxide assimilation and the chlorophyll fluorescence-based photosynthetic electron transport rate were also higher than WT plants. The OX plants displayed significant reductions in the rate of photorespiration relative to gross photosynthesis and increase in the ratio of the photosynthetic electron flow attributable to carboxylation reactions over that attributable to oxygenation reactions. GD, HD and OX plants accumulated significantly higher biomass and seed weight. Soluble sugars were significantly increased in GD and HD plants, while the starch levels were higher in all transgenic plants. The transcriptomic analysis of GD plants revealed 650 up-regulated genes mainly related to photosynthesis, photorespiratory pathway, sucrose metabolism, chlorophyll biosynthesis and glutathione metabolism. Conclusion: This study revealed the potential of introduced cyanobacterial pathway genes to enhance photosynthetic and growth-related parameters. The upregulation of genes related to different pathways provided evidence of the underlying mechanisms involved particularly in GD plants. However, transcriptomic profiling of HD and OX plants can further help to identify other potential mechanisms involved in improved plant productivity.

Aphids are agricultural pest insects that transmit viruses and cause feeding damage on a global scale. Current pest control practices involving the excessive use of synthetic insecticides over many years have resulted in aphid resistance to a number of pesticides. In nature, plants produce secondary metabolites during their interaction with insects and these metabolites can act as toxicants, antifeedants, anti-oviposition agents and deterrents towards the insects. In a previous study, we demonstrated that the butanol fraction from a crude methanolic extract of an important plant species, Isodon rugosus showed strong insecticidal activity against the pea aphid, Acyrthosiphon pisum. To further explore this finding, the current study aimed to exploit a bioactivity-guided strategy to isolate and identify the active compound in the butanol fraction of I. rugosus. As such, reversed-phase flash chromatography, acidic extraction and different spectroscopic techniques were used to isolate and identify the new compound, rosmarinic acid, as the bioactive compound in I. rugosus. Insecticidal potential of rosmarinic acid against A. pisum was evaluated using standard protocols and the data obtained was analyzed using qualitative and quantitative statistical approaches. Considering that a very low concentration of this compound (LC₉₀ = 5.4 ppm) causes significant mortality in A. pisum within 24 h, rosmarinic acid could be exploited as a potent insecticide against this important pest insect. Furthermore, I. rugosus is already used for medicinal purposes and rosmarinic acid is known to reduce genotoxic effects induced by chemicals, hence it is expected to be safer compared to the current conventional pesticides. While this study highlights the potential of I. rugosus as a possible biopesticide source against A. pisum, it also provides the basis for further exploration and development of formulations for effective field application.

Aphids are agricultural pest insects that transmit viruses and cause feeding damage on a global scale. Current pest control involving the excessive use of synthetic insecticides over decades has led to multiple forms of aphid resistance to most classes of insecticides. In nature, plants produce secondary metabolites during their interaction with insects and these metabolites can act as toxicants, antifeedants, anti-oviposition agents and deterrents towards the insects. In a previous study, we demonstrated that the butanol fraction from a crude methanolic extract of an important plant species, Isodon rugosus showed strong insecticidal activity against the pea aphid, Acyrthosiphon pisum . It was however not known as which compound was responsible for such activity. To further explore this finding, current study aimed to exploit a bioactivity-guided strategy to isolate and identify the active compound in the butanol fraction of I. rugosus . As such, reversed-phase flash chromatography, acidic extraction and different spectroscopic techniques were used to isolate and identify the new compound, rosmarinic acid as the bioactive compound in I. rugosus . Insecticidal activity of rosmarinic acid was carried out using standard protocols on A. pisum . The data was analyzed using qualitative and quantitative statistical approaches. Considering that a very low concentration of this compound (LC ₉₀ = 5.4 ppm) causes significant mortality in A. pisum within 24 h, rosmarinic acid could be exploited as a potent insecticide against this important pest insect. Furthermore, I. rugosus is already used for medicinal purposes and rosmarinic acid is known to reduce genotoxic effects induced by chemicals, hence it is expected to be safer compared to the current conventional pesticides. While this study highlights the potential of I. rugosus as a possible biopesticide source against A. pisum , it also provides the basis for further exploration and development of formulations for effective field application.

Dye effluents and their degradation products disrupt the aquatic ecosystem functioning. Corncob was used as a low-cost biosorbent for decolorization of methylene blue (MB) dye. Batch and fixed-bed column adsorption were performed by varying temperature, pH, initial dye concentration, adsorbent dose, particle size, and bed height, flow rate and inlet dye concentration, respectively. High MB adsorption capacities of corncob were attained at pH 9, i.e. 45.86 mg g⁻¹, 91.7%. Equilibrium data was best described by Langmuir II (R² = 0.999) followed by Freundlich (R² = 0.994) and Halsey (R² = 0.994) isotherm models, which indicates the favorable adsorption of MB dye onto corncob adsorbent. Moreover, chemisorption nature of corncob was confirmed through Dubinin–Radushkevich (E = 16.01 kJ mol⁻¹) and the best fit of pseudo-second-order kinetic model. Thermodynamic studies revealed spontaneous (∆G < 0) and endothermic (∆H > 0) nature of reaction with increased randomness (∆S > 0) at the solid–liquid interface. The breakthrough curves were predicted using Thomas and BDST models. BDST reflected that 2.26 min were required to exhaust 1 cm of the fixed-bed column. MB dye-loaded corncob adsorbent could be regenerated (80%) and reused using 0.1 M acetic acid.