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The agricultural sustainability concept considers higher food production combating biotic and abiotic stresses, socio-economic well-being, and environmental conservation. On the contrary, global warming-led climatic changes have appalling consequences on agriculture, generating shifting rainfall patterns, high temperature, CO2, drought, etc., prompting abiotic stress conditions for plants. Such stresses abandon the plants to thrive, demoting food productivity and ultimately hampering food security. Though environmental issues are natural and cannot be regulated, plants can still be enabled to endure these abnormal abiotic conditions, reinforcing the stress resilience in an eco-friendly fashion by incorporating fungal endophytes. Endophytic fungi are a group of subtle, non-pathogenic microorganisms establishing a mutualistic association with diverse plant species. Their varied association with the host plant under dynamic environments boosts the endogenic tolerance mechanism of the host plant against various stresses via overall modulations of local and systemic mechanisms accompanied by higher antioxidants secretion, ample enough to scavenge Reactive Oxygen Species (ROS) hence, coping over-expression of defensive redox regulatory system of host plant as an aversion to stressed condition. They are also reported to ameliorate plants toward biotic stress mitigation and elevate phytohormone levels forging them worthy enough to be used as biocontrol agents and as biofertilizers against various pathogens, promoting crop improvement and soil improvement, respectively. This review summarizes the present-day conception of the endophytic fungi, their diversity in various crops, and the molecular mechanism behind abiotic and biotic resistance prompting climate-resilient aided sustainable agriculture.

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The aim of this work is to explore the possibility of using mixed culture of mesophilic sulfate-reducing bacteria (SRB) for retrieval of toxic and carcinogenic Cr (VI) from synthetic solution. In order to treat Cr (VI) containing wastewater effectively, SRB culture was adapted to 50 mg/L Cr (VI) and maintained through repeated sub-culturing to enhance the growth and activity of SRB. Batch biosorption experiments were carried out in glass serum vials by cultured SRB, accomplishing the removal of 82.1% Cr (VI), 76.9% sulfate, 85.7% COD under the following optimized conditions: pH 7, hydraulic retention time (HRT) 7 days, temperature 37 • C and initial Cr (VI) concentration of 50 mg/L. Further sorption experiments were conducted on synthetic wastewater under optimal operational conditions and resulted in 89.2% Cr (VI), 81.9% COD and 95.3% sulfate reduction from simulated wastewater. The results of this work contributed to a better understanding of metal uptake by biogenic sulfides and would be beneficial in the development of potential biosorbents that possess high capacities for Cr (VI) uptake from aqueous environments.

The present study points to the relevance of the earthworms-microorganism"s symbiotic and synergistic interactions that drive the wastewater treatment by identifying the most essential mechanisms underlying the removal of contaminants during vermifiltration technology. Previous studies have showed the presence of earthworms improves treatment performance of vermifilter (VF), but earthworm microbial community dynamics, their structure and functional characteristics in VF were not fully investigated. To investigate the effects of earthworms on the inherent microbial community of the VF, the present study envisages the dynamics of the complex symbiosis of earthworms & microorganisms associated to the treatment mechanisms. In this study, the design, operations and performance evaluation and influent, effluent and filter media layer were investigated for microbial diversity inside the earthworm population, along with the antimicrobial activity, enzymatic activity, and protein profiling assays. The results showed that earthworm gut microbial communities were dominated by Gammaproteobacteria, and the percentages arrived to 59-60% of the microbial species detected, while filter media layer showed presence of Firmicutes and Actinobacteria. The protein profiling of the microbiota associated with the VF showed that earthworms feeding and earthworm-microorganism . CC-BY-NC 4.0 International license available under a (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made interaction were responsible for enhanced treatment performance. The finding provides an insight into the complex earthworm microbial dynamics and mechanisms for wastewater treatment in VF. Furthermore, earthworm predation strongly regulated microbial biomass while improving microbial activity, and is deciphered as the possible mechanisms behind the vermifiltration technology.