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Soil health is the foundation of sustainable agriculture, and its preservation is paramount in global arsenic (As) contamination challenges. Soil As contamination is a critical issue for environmental and agricultural sustainability. Rapid global urbanization and agricultural and industrial expansion release toxic metal (loid)s including As into the soil. Arsenic contamination disrupts the rhizosphere ecosystem, affecting plant health, microbial communities, and overall soil functionality. Ensuring soil health in the face of As contamination is imperative for human well-being and for developing a resilient, sustainable environment. This review signifies the need for comprehensive strategies to revitalize soil ecosystems, promoting resilience and long-term ecological balance. Advanced biotechnological approaches, particularly bioremediation including phytoremediation, microbial remediation, mycoremediation, nano-remediation, and other integrative strategies, are highlighted for their effectiveness in addressing As contamination and promoting soil health. Conventional physico-chemical techniques make soil unsuitable for agriculture by disrupting the microenvironment. Consequently, the urgent need for remediation of As-contaminated soil demands the adoption of eco-friendly and sustainable approaches, such as bioremediation, phytoremediation, and rhizoremediation, to enhance soil health.Development of transgenic lines and genetically modified organisms are effective tools in reducing the As burden. Bacteria including Sphingomonas desiccabilis, Bacillus subtilis and Bacillus idriensis expressing the arsM gene all show promising results to reduce the As burden. Transgenic rice, incorporating the arsM gene from Rhodopseudomonas palustris, demonstrated 10 times more volatile arsenicals and reduced As accumulation in the grain. Additionally, the use of As-hyperaccumulating plants and conventional methods, like chemical-assisted phytoextraction, show potential for decontaminating As- contaminated soil. Future research should explore the contributions of novel biotechnological strategies to enhance soil health in regions affected by As contamination.

Background: Lead (Pb) toxicity affects growth, mineral nutrient homeostasis, water status and yield of plants. To avoid Pb entry into humans via the food chain, remediation of contaminated sites is required. This study was focused on the evaluation of effects of Pb on Moringa oleifera, an efficient metal accumulator plant, for the prospective use in Pb mitigation from the soil. Methods: M. oleifera seedlings (10-day old) were treated with different concentrations of Pb (1, 2, 3 and 5 mM) and morphological,biochemicaland molecular parameters and Pb accumulation were analysed at 10, 20 and 30 days. Results: The results showed high Pb uptake by plants in a concentration- and duration-dependent manner. The maximum Pb concentration was found to be 500 mg kg−1in roots and 224 mg kg−1 in shoots, respectively at 5 mM Pb after 30 days. In response to Pb accumulation, plants depicted significant increase in the level of proline (0.49 µmol g–1 FW), polyphenol (75.83 mg g–1 FW), and metallothionein protein (93.55 µmol g-1 × 10−3). In addition, the activity of antioxidant enzymes (ascorbate peroxidase:APX, catalase:CAT and glutathione reductase:GR)was also enhanced in Pb treated plants as compared to that of control plants. The expression of genes of enzymes (APX and CAT) was also up-regulated. Conclusion: It was concluded from the present results that M. oleifera is a Pb tolerant plant species with a significant capacity for Pb accumulation.Thus, this plant can be used for plantation at Pb-contaminated sites for restoration purposes.

Multifunctional plant growth-promoting bioinoculants are used to enhance growth, harvest yields, and add economic value to agricultural crops. In this study, such bioinoculant, BC-II-20 (Pseudomonas sp.), was isolated from the rhizospheric soil of a medicinal plant Bergenia ciliata from the Garhwal Himalayas, Uttarakhand, India. After characterization, supplementation with Pseudomonas sp. was used to study growth stimulation in a commercially important medicinal plant, Andrographis paniculata (Kalmegh), and it depicted enhanced physiological growth parameters under controlled conditions. Bacterial seed priming and also supplementation led to early and increased germination and plants displayed better vegetative growth during the entire growth stages. Early initiation of flowers and the appearance of pods occurred in inoculated plants, ultimately leading to the reduction in the life cycle of the plant. At the time of harvesting, there was an increase in the physiological parameters such as shoot length (38%), root length (14%), fresh weight (57%), dry weight (60%), number of panicles, and root branching. Photosynthetic efficiency was also higher, and ultimately, overall plant growth was improved by bacterial inoculation. The eco-friendly and sustainable use of this bioinoculant will provide an alternative to harmful chemical fertilizers and has become increasingly important. In conclusion, we reported a promising bioinoculant having plant growth-promoting traits, which promotes growth and development in A. paniculata and may be applied to other plants also.

The present article represents the data for analysis of microbial consortium (P.putida+C.vulgaris) mediated amelioration of arsenic toxicity in rice plant. In the current study the transcriptome profiling of treated rice root and shoot was performed by illumina sequencing (Platform 2000). To process the reads and to analyse differential gene expression, Fastxtoolkit, NGSQCtoolkit, Bowtie 2 (version 2.1.0), Tophat program (version 2.0.8), Cufflinks and Cuffdiff programs were used. For Proteome profiling, total soluble proteins in shoot of rice plant among different treatments were extracted and separated by 2D poly acrylamide gel electrophoresis (PAGE) and then proteins were identified with the help of MALDI-TOF/TOF. In gel based method of protein identification, the isoelectric focusing machine (IPGphor system,Bio-Rad USA), gel unit (SDS-PAGE) and MALDI-TOF/TOF (4800 proteomic analyzer Applied Biosystem, USA) were used for successful separation and positive identification of proteins. To check the differential abundance of proteins among different treatments, PDQuest software was used for data analysis. For protein identification, Mascot search engine (http://www.matrixscience.com) using NCBIprot/SwissProt databases of rice was used. The analyzed data inferred comprehensive picture of key genes and their respective proteins involved in microbial consortium mediated improved plant growth and amelioration of As induced phyto-toxicity in rice. For the more comprehensive information of data, the related full-length article entitled “Microbial consortium mediated growth promotion and Arsenic reduction in Rice: An integrated transcriptome and proteome profiling” may be accessed.

The adverse effects of arsenic (As) contamination are well known. Rice is a staple food for 50% of the world population but the accumulation of As into rice hampers the food security and safety. Thus the amelioration of As stress and reduction of As levels in rice are needed. In this study, transcriptome (Illumina sequencing) and proteome (2D gel electrophoresis) explored mechanisms of consortium (P. putida+C. vulgaris) mediated growth promotion and As amelioration in rice. The rice seedlings grown hydroponically in the Hewitt nutrient medium and after acclimatization, exposed to 50 µM As alone as well as with microbial consortium to observe the impact at morphological and molecular level. The inoculation of microbial consortium significantly ameliorated the As toxicity, improved growth of root hairs and maintained cellular integrity of the epidermis, exodermis and the stele region during As exposure. Several genes showed differential expression in As and As+P. putida. Down-regulation of As transporters (OsPIP2;2 and OsPIP2;3, OsTIP2;1) and higher expression of WRKY gene (WRKY28) during As+P. putida+C.vulgaris suggested reduction of As uptake in rice. The up-regulation of nutrient elements transporters (OsZIFL9, OsZIFL5, OsZIFL12 and OsZIP2, OsYSL15 and OsCOPT6) in the presence of consortium indicated the improved nutrient status of rice. Higher expression of regulatory elements like auxin/indole 3 acetic acid (AUX/IAA), WRKY and myeloblastosis (MYB) TFs and down-regulation of defense responsive genes such Glutathione-S-transferase, Peroxidase and Glutaredoxinduring As+P. putida+C.vulgaris exposure was also observed. Proteome profiling demonstrated differential abundance of proteins involved in photosynthesis (chlorophyll a/b binding protein, photosystem I Fe-S centre), energy metabolism (ATP synthase subunit beta) transport, signaling (tubulin 1, actin 1), defense (glutathione S-transferase, phenylalanine ammonia lyase) and amino acid metabolism (cysteine synthase, glutamine synthetase), which supported the As ameliorative and growth-promoting potential of microbial consortium during As stress in rice plants. The study gives comprehensive information about gene and protein changes in rice plants in As+consortium exposure.

Different natural and anthropogenic global events and activities such as urban settlements and industrial development have led to a build-up of numerous pollutants in the environment, creating problems for nature and human health. Among the pollutants, metal(loid)s are persistent and ubiquitously present in the soil, water, and air. The presence of high concentrations of metal(loid)s in water is of serious concern, as water is a basic necessity of humans and plants. Through irrigation, metal(loid)s enter and accumulate in plants, and subsequently reach humans via food. There is demand for sustainable and practical technologies for tackling the challenge of metal(loid) pollution. Nanotechnology has found its place in diverse fields including cosmetics, sensors, remediation, and medicine. Nanoremediation is an effective, feasible, and sustainable technology for cleaning up water contaminated with metal(loid)s and other chemicals. The versatility of nanomaterials is huge due to their differences in size, shape, surface chemistry, and chemical composition. This review sheds light on different nanoparticles (NPs) used for water remediation and summarizes key recent findings. The successful application of NPs in laboratory studies warrants their potential use in water clean-up from a small to a large scale.

Plants live under different biotic and abiotic stress conditions, and, to cope with the adversity and severity, plants have well-developed resistance mechanisms. The mechanism starts with perception of the stimuli followed by molecular, biochemical, and physiological adaptive measures. The family of LRR-RLKs (leucine-rich repeat receptor-like kinases) is one such group that perceives biotic and abiotic stimuli and also plays important roles in different biological processes of development. This has been mostly studied in the model plant, Arabidopsis thaliana, and to some extent in other plants, such as Solanum lycopersicum, Nicotiana benthamiana, Brassica napus, Oryza sativa, Triticum aestivum, Hordeum vulgare, Brachypodium distachyon, Medicago truncatula, Gossypium barbadense, Phaseolus vulgaris, Solanum tuberosum, and Malus robusta. Most LRR-RLKs tend to form different combinations of LRR-RLKs-complexes (dimer, trimer, and tetramers), and some of them were observed as important receptors in immune responses, cell death, and plant development processes. However, less is known about the function(s) of LRR-RLKs in response to abiotic and biotic stresses. Here, we give recent updates about LRR-RLK receptors, specifically focusing on their involvement in biotic and abiotic stresses in the model plant, A. thaliana. Furthermore, the recent studies on LRR-RLKs that are homologous in other plants is also reviewed in relation to their role in triggering stress response processes against biotic and abiotic stimuli and/or in exploring their additional function(s). Furthermore, we present the interactions and combinations among LRR-RLK receptors that have been confirmed through experiments. Moreover, based on GENEINVESTIGATOR microarray database analysis, we predict some potential LRR-RLK genes involved in certain biotic and abiotic stresses whose function and mechanism may be explored.

Hydrilla verticillata (L.f.) Royle is a widely distributed aquatic weed having prolific growth habits and a wide range of habitat. It can tolerate a wide range of physical and chemical conditions of water and can survive in low nutrient supply. Hydrilla is a potential accumulator of several metals and metalloids. The accumulation potential of Hydrilla plants is attributable to induced synthesis of thiol (-SH) containing ligands like glutathione and phytochelatins. Further, the uptake of metal(loid)s from both roots and leaves and movement in acropetal and basipetal directions allows plants to take up large quantity of metal(loid)s in short time span. Secondarily, antioxidant system is comprising of enzymatic and non-enzymatic components was found to rescue plants from metal(loid) induced oxidative stress. The used biomass of Hydrilla can be further utilized for composting, briquetting, pyrolysis and gasification. The high calorific fuel obtained from Hydrilla was found to have high heating value (44.06 MJ/kg) and low oxygen content (

Salinity stress is one of the major abiotic stresses threatening sustainable crop production worldwide. The extent of salinity affected area is expected to cover about 50% of total agricultural land by 2050. Salinity stress produces various detrimental effects on plants’ physiological, biochemical, and molecular features and reduces productivity. The poor plant growth under salinity stress is due to reduced nutrient mobilization, hormonal imbalance, and formation of reactive oxygen species (ROS), ionic toxicity, and osmotic stress. Additionally, salinity also modulates physicochemical properties and reduces the microbial diversity of soil and thus decreases soil health. On the other hand, the demand for crop production is expected to increase in coming decades owing to the increasing global population. Conventional agricultural practices and improved salt-tolerant crop varieties will not be sufficient to achieve the yields desired in the near future. Plants harbor diverse microbes in their rhizosphere, and these have the potential to cope with the salinity stress. These salinity-tolerant plant growth-promoting bacteria (PGPB) assist the plants in withstanding saline conditions. These plant-associated microbes produce different compounds such as 1-aminocyclopropane-1-carboxylate (ACC) deaminase, indole-3-acetic acid (IAA), antioxidants, extracellular polymeric substance (EPS), and volatile organic compounds (VOC). Additionally, the naturally associated microbiome of plants has the potential to protect the host through stress avoidance, tolerance, and resistance strategies. Recent developments in microbiome research have shown ways in which novel microbe-assisted technologies can enhance plant salt tolerance and enable higher crop production under saline conditions. This focused review article presents the global scenario of salinity stress and discusses research highlights regarding PGPB and the microbiome as a biological tool for mitigation of salinity stress in plants.

Arsenic (As) is a toxic metalloid classified as group 1 carcinogen. The presence of As in high concentrations in paddy soil and irrigation water results into high As accumulation in rice grains posing a threat to the health of millions of people worldwide. The main reason for As contamination is the biogeochemical weathering of rocks and the release of bound As into groundwater. Human interventions through intensive agricultural practices and excessive groundwater consumption have contributed greatly to the prevailing As contamination. The flooded cultivation practice of rice favors the accumulation of As in rice grains. The formation of iron (Fe) plaque on paddy root surfaces, changes in the level of Fe and manganese (Mn) hydro(oxides), soil organic matter, soil pH, soil redox potential, and microbial activities under flooding conditions influence concentrations of various As species in the water–soil–paddy agroecosystem and favor the predominance of highly mobile arsenite [As(III)]. Once inside the rice plant, the concentration of As is regulated by arsenate reduction, arsenite efflux, root-to-shoot translocation, and vacuolar sequestration of As. The detailed understanding gained about the factors affecting As dynamics in soil and transport in rice plants may be helpful in developing feasible methods for sustainable cultivation of rice plants with low grain As. There is also need to ensure high production yields as well as grain quality to achieve the goals of sustainable development. This article discusses the aspects of As in the water–soil–paddy agroecosystem and presents suitable strategies to reduce the As load in rice grains.

The consequences of heavy metal contamination are progressively degrading soil quality in this modern period of industry. Due to this reason, improvement of the soil quality is necessary. Remediation is a method of removing pollutants from the root zone of plants in order to minimize stress and increase yield of plants grown in it. The use of plants to remove toxins from the soil, such as heavy metals, trace elements, organic chemicals, and radioactive substances, is referred to as bioremediation. Biochar and fly ash techniques are also studied for effectiveness in improving the quality of contaminated soil. This review compiles amelioration technologies and how they are used in the field. It also explains how nanoparticles are becoming a popular method of desalination, as well as how they can be employed in heavy metal phytoremediation.

Zinc is an essential element that is also renowned for widespread contamination and toxicity at high concentrations. The present study was carried out to analyze the responses induced by lower, as well as higher, doses of zinc (0–200 mg/L), in the form of zinc oxide nanoparticles (ZnO NPs) in wheat and maize, for a period of 21 days. Accumulation of zinc increases with increasing Zn doses in both wheat and maize, with higher doses being in wheat (121 mg/kg in root and 66 mg/kg in shoot) than in maize (95 mg/kg in root and 48 mg/kg in shoot). The activity of alpha-amylase showed increase, while that of dehydrogenase decline, in response to ZnO NPs. The length and biomass of plants and photosynthetic pigments increased slightly upon ZnO NPs supply. Malondialdehyde content showed a progressive increase in root and shoot of both plants. However, in response, antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, and catalase) showed increase up to lower concentrations (100 mg/L) of ZnO NPs but decline variably at higher levels (150–200 mg/L) in wheat and maize. The results suggest that lower supply of ZnO NPs (100 mg/L) could be stimulatory to the growth of plants and can be recommended as a Zn fertilizer source for crop production.

Arsenic contamination of the environment is a serious problem threatening the health of millions of people exposed to arsenic (As) via drinking water and crops grown in contaminated areas. The remediation of As-contaminated soil and water bodies needs to be sustainable, low-cost and feasible to apply in the most affected low-to-middle income countries, like India and Bangladesh. Phytoremediation is an aesthetically appreciable and successful approach that can be used for As decontamination with use of the best approach(es) and the most promising plant(s). However, phytoremediation lacks the required speed and sometimes the stress caused by As could diminish plants’ potential for remediation. To tackle these demerits, we need augment plants’ potential with appropriate technological methods including microbial and nanoparticles applications and genetic modification of plants to alleviate the As stress and enhance As accumulation in phytoremediator plants. The present review discusses the As phytoremediation prospects of soil and water bodies and the usefulness of various plant systems in terms of high biomass, high As accumulation, bioenergy potential, and economic utility. The potential and prospects of assisted phytoremediation approaches are also presented.

Abiotic stress in plants is a crucial issue worldwide, especially heavy-metal contaminants, salinity, and drought. These stresses may raise a lot of issues such as the generation of reactive oxygen species, membrane damage, loss of photosynthetic efficiency, etc. that could alter crop growth and developments by affecting biochemical, physiological, and molecular processes, causing a significant loss in productivity. To overcome the impact of these abiotic stressors, many strategies could be considered to support plant growth including the use of nanoparticles (NPs). However, the majority of studies have focused on understanding the toxicity of NPs on aquatic flora and fauna, and relatively less attention has been paid to the topic of the beneficial role of NPs in plants stress response, growth, and development. More scientific attention is required to understand the behavior of NPs on crops under these stress conditions. Therefore, the present work aims to comprehensively review the beneficial roles of NPs in plants under different abiotic stresses, especially heavy metals, salinity, and drought. This review provides deep insights about mechanisms of abiotic stress alleviation in plants under NP application.

Ulmus pumila L. is an excellent afforestation and biofuel tree that produces high-quality wood, rich in starch. In addition, U. pumila is highly adaptable to adverse environmental conditions, which is conducive to its utilization for vegetating saline soils. However, little is known about the physiological responses and transcriptional regulatory network of U. pumila under salt stress. In this study, we exposed five main cultivars in saline–alkali land (Upu2, 5, 8, 11, and 12) to NaCl stress. Of the five cultivars assessed, Upu11 exhibited the highest salt resistance. Growth and biomass accumulation in Upu11 were promoted under low salt concentrations (Arabidopsis plants under salt stress. Our findings clarify the physiological and transcriptional regulators that promote or inhibit growth under environmental stress. The identification of salt-responsive hub genes directly responsible for photosynthesis and starch synthesis or metabolism will provide targets for future genetic improvements.

Plant growth and development is adversely affected by different kind of stresses. One of the major abiotic stresses, salinity, causes complex changes in plants by influencing the interactions of genes. The modulated genetic regulation perturbs metabolic balance, which may alter plant’s physiology and eventually causing yield losses. To improve agricultural output, researchers have concentrated on identification, characterization and selection of salt tolerant varieties and genotypes, although, most of these varieties are less adopted for commercial production. Nowadays, phenotyping plants through Machine learning (deep learning) approaches that analyze the images of plant leaves to predict biotic and abiotic damage on plant leaves have increased. Here, we review salinity stress related markers on molecular, physiological and morphological levels for crops such as maize, rice, ryegrass, tomato, salicornia, wheat and model plant, Arabidopsis. The combined analysis of data from stress markers on different levels together with image data are important for understanding the impact of salt stress on plants.

Arsenic (As) contamination is a serious issue throughout the world. The scale of problem is being realized to be even greater with the discovery of new As contaminated regions with time. Rice is a staple crop across the world with approximately half of the world population dependent on rice for their daily dietary intake especially in Southeast Asian countries. It is not only the consumption of rice grains but also food products based on rice, which contribute toward As exposure to humans. Plant growth promoting microorganisms (PGPMs) constitute a diverse group of microorganisms including bacteria, fungi and microalgae. These are associated with the rhizospheric zone of plants. They improve plant growth through different mechanisms like increase of nutrients level in plants, improved soil quality, siderophore and hormone production, changes in biochemical properties of plants etc. Another important assistance imparted by PGPMs is the altered speciation of As in the soil through methylation and subsequent change in the bioavailability of As to the plants. Further, a change in As speciation also affects As uptake and transport in plants. The purpose of this review is to discuss importance of PGPM association in As toxicity amelioration in plants along with favorably reducing As concentrations in crop plants or increasing As accumulation in phytoremediator plants. This review also presents mechanisms of action of PGPMs and describes both laboratory- and field-studies on the application of PGPMs for tackling As-contamination. The future prospects of successful utilization of PGPMs are also discussed.

Arsenic (As) is a non-essential toxic metalloid whose elevated concentration in rice grains is a serious issue both for rice yield and quality, and for human health. The rice-As interactions, hence, have been studied extensively in past few decades. A deep understanding of factors influencing As uptake and transport from soil to grains can be helpful to tackle this issue so as to minimize grain As levels. As uptake at the root surface by rice plants depends on factors like iron plaque and radial oxygen loss. There is involvement of a number of transporters viz., phosphate transporters and aquaglyceroporins in the uptake and transport of different As species and in the movement to subcellular compartments. These processes are also affected by sulfur availability and consequently on the level of thiol (-SH)-containing As binding peptides viz., glutathione (GSH) and phytochelatins (PCs). Further, the role of phloem in As movement to the grains is also suggested. This review presents a detailed map of journey of As from soil to the grains. The implications for the utilization of available knowledge in minimizing As in rice grains are presented.

Phosphorus (P) is an essential element required for incorporation into several biomolecules and for various biological functions; it is, therefore, vital for optimal growth and development of plants. The extensive research on identifying the processes underlying the uptake, transport, and homeostasis of phosphate (Pi) in various plant organs yielded valuable information. The transport of Pi occurs from the soil into root epidermal cells, followed by loading into the root xylem vessels for distribution into other plant organs. Under conditions of Pi deficiency, Pi is also translocated from the shoot to the root via the phloem. Vacuoles act as a storage pool for extra Pi, enabling its delivery to the cytosol, a process which plays an important role in the homeostatic control of cytoplasmic Pi levels. In mitochondria and chloroplasts, Pi homeostasis regulates ATP synthase activity to maintain optimal ATP levels. Additionally, the endoplasmic reticulum functions to direct Pi transporters and Pi toward various locations. The intracellular membrane potential and pH in the subcellular organelles could also play an important role in the kinetics of Pi transport. The presented review provides an overview of Pi transport mechanisms in subcellular organelles, and also discusses how they affect Pi balancing at cellular, tissue, and whole-plant levels.