Abiotic stresses are the most significant factors reducing agricultural productivity. Plants face extreme environmental conditions that may affect their biological mechanisms, thereby influencing their growth and development. Microorganisms possess substantial metabolites that aid in helping plants mitigate abiotic stresses. Plants’ interaction with microbes constitutes a diversified ecosystem, as sometimes both the partners share a mutualistic relationship. Endophytes, plant-growth-promoting rhizobacteria (PGPRs), and arbuscular mycorrhizal fungi (AMFs) are examples of microorganisms that play an essential role in alleviating abiotic stresses and, hence, improving plant growth. The plant–microbe interaction leads to the modulation of complex mechanisms in the plant cellular system. Moreover, the residing microbial flora also inhibits the phytopathogens, therefore, it becomes part of plants’ innate defense system. Keeping in view the growing environmental concerns, it is important to identify the role of the plant microbiome in the transportation of nutrients to maintain sustainable production. Furthermore, it is important to identify the factors enabling plants to recruit beneficial microbial species and how to deal with the potential pathogens. Therefore, this review aims to summarize the impacts of various abiotic stressors on agricultural productivity and the role of beneficial microorganisms in mitigating the negative effects of abiotic stresses. The literature review also shows that the beneficial microbes, including PGPRs, AMFs, and endophytes, adopt various mechanisms for ameliorating the negative effects of various stresses. It has been observed that biochar and microbes, either individually or in combination, can play a significant role in maintaining plant growth under stress conditions. Although conventional inoculation of beneficial microbes mitigates abiotic stresses and enhances productivity, the advancement in genetic engineering would help transfer specific genes from the microbes to plants to aid in abiotic stress mitigation.

Plant salinity resistance results from a combination of responses at the physiological, molecular, cellular, and metabolic levels. This article focuses on plant stress tolerance mechanisms for controlling ion homeostasis, stress signaling, hormone metabolism, anti-oxidative enzymes, and osmotic balance after nanoparticle applications. Nanoparticles are used as an emerging tool to stimulate specific biochemical reactions related to plant ecophysiological output because of their small size, increased surface area and absorption rate, efficient catalysis of reactions, and adequate reactive sites. Regulated ecophysiological control in saline environments could play a crucial role in plant growth promotion and survival of plants under suboptimal conditions. Plant biologists are seeking to develop a broad profile of genes and proteins that contribute to plant salt resistance. These plant metabolic profiles can be developed due to advancements in genomic, proteomic, metabolomic, and transcriptomic techniques. In order to quantify plant stress responses, transmembrane ion transport, sensors and receptors in signaling transduction, and metabolites involved in the energy supply require thorough study. In addition, more research is needed on the plant salinity stress response based on molecular interactions in response to nanoparticle treatment. The application of nanoparticles as an aspect of genetic engineering for the generation of salt-tolerant plants is a promising area of research. This review article addresses the use of nanoparticles in plant breeding and genetic engineering techniques to develop salt-tolerant crops.

Heavy metals are notoriously toxic pollutants which can potentially harm living beings and are serious health hazards. The aim of the present study was to assess the levels of cadmium (Cd) and nickel (Ni) throughout the year in the urban areas of the densely populated industrial city of Faisalabad in eight commonly raised ornamental tree species with phytoremediation potential. High levels of Cd and Ni were recorded in all study areas, with spatio-temporal heterogeneity. Heavy metal uptake varied among plant species with Cd and Ni in soil ranging between 6.78–8.57 mgkg⁻¹ and 46.31–55.85 mg kg⁻¹ respectively. Plant species accumulated 6.73–8.98 mg kg⁻¹ Cd and 26.42–52.50 mg kg⁻¹ Ni with Conocarpus erectus, Dalbergia sissoo and Bismarckia nobilis showing higher accumulation potential than others. Dalbergia sissoo accumulated the highest levels of Ni and was shown to a good bio-indicator for this metal. The highest accumulation of Cd was recorded in Conocarpus erectus (9 mg kg⁻¹), followed by Dalbergia sissoo (8.2 mg kg⁻¹) and Bismarckia nobilis (8.1 mg kg⁻¹) while the leaves of Azadirachta indica retained the lowest (6.3 mg kg⁻¹) Cd levels. The highest levels of metals were accumulated by all species during the summer season while the second highest were observed in the autumn season. The study revealed that ornamental species can help in minimizing heavy metal pollution as well as providing green space in urban settings for maintaining a clean and healthy environment.

The experiment was conducted to isolate and screen fungal strain and optimization of solid-state fermentation conditions for enhanced production of β-glucosidase. Different fungal cultures were isolated and screened for β-glucosidase production. The physicochemical and nutritional parameters were optimized for enhanced production of β-glucosidase from higher producer. Among all the isolates the isolate which exhibited highest β-glucosidase potential was identified and assigned the code as Aspergillus niger MBT-2. The optimum β-glucosidase production was obtained in M5 medium containing wheat bran after 72 hrs of incubation at 40°C, pH 6 and 20 ml of moisture contents. In addition to this 2% fructose and 2% yeast extract proved to be best carbon and nitrogen sources, respectively and gave maximal enzyme productivity. The exploitation of agricultural by products as a substrate reduced the production cost of enzyme and makes the process economical. The Aspergillus niger MBT-2 has promising potential of bioconversion of low-cost material into valuable product like β-glucosidase.