Sardar Vallabh Bhai Patel University of Agriculture and Technology

Cold environments are potential reservoirs of psychrophilic microbes with well-developed survival strategies for overcoming sub-zero temperatures. Psychrophilic microbes survive under extremities of cold by diverse mechanisms such as altered membrane fluidity, cold shock proteins, antifreeze proteins, chaperones, and production of ice nucleating proteins. Cold adaptive microbes possess unique abilities of producing novel and potential psychrozymes which serve as valuable biocatalysts for industry. Psychrozymes such as the amylases, lipases, cellulases, xylanases and pectinases with potential application in food, textile, pharmaceutical, and detergent industries have been reported. The present view highlights the strategies adopted by psychrophiles to survive in cold habitats and major applications of psychrozymes in different industries.

A cost-effective and environmentally sustainable approach was employed to fabricate zinc oxide nanoparticles (ZnONPs) using aqueous, ethanolic, and methanolic extracts of Bacopa monnieri (L.). ZnONPs are gaining increasing importance and are widely explored by many researchers due to their potential therapeutic applications in anti-inflammatory, antifungal, anti-diabetic, antibacterial, antioxidant, and wound-healing effects. Contrary to traditional chemical and physical synthesis methods that often require harmful reagents as reducing and stabilising agents, this study employs an environmentally friendly approach through plant-mediated green synthesis, utilising phytochemicals as natural reducing and stabilising agents. The synthesis of ZnONPs was validated through UV–Visible spectroscopy, which displayed distinct excitonic absorption peaks within the range of approximately 320–350 nm. The analysis using Transmission Electron Microscopy (TEM) indicated the presence of quasi-spherical nanoparticles, with average particle sizes varying between approximately 16–24 nm, contingent upon the solvent extract utilised. The FTIR spectra displayed significant Zn–O stretching vibrations within the range of approximately 450–550 cm⁻¹, in addition to functional groups linked to phytochemicals that play a crucial role in capping and stabilisation. The confirmation of structural and compositional analyses was achieved through the application of XRD and EDX techniques. This study offers a thorough solvent-based comparative analysis of ZnONPs synthesised from three distinct extracts (aqueous, ethanolic, and methanolic) of Bacopa monnieri (L.), emphasising the variations in particle size, optical properties, and stabilisation behaviour that depend on the extract used, which may have significant implications for future pharmaceutical applications.

Initial soil fertility affects fertilizer recommendations derived from soil test crop response. Therefore, predicting post-harvest soil available nitrogen (AN), phosphorus (AP) and potassium (AK) by this technique reduces the dependency on frequent analysis of post-harvest soil analysis. To investigate this, a field experiment was conducted at G.B. Pant University of Agriculture and Technology, Pantnagar from 2016 to 2018. The primary goal was to develop predictive equations for post-harvest soil test values (PHSTVs) for AN, AP and AK for direct-seeded rice–wheat cropping sequence (DSR-W-CS) utilizing an inductive and targeted yield model. The fractional factorial design was employed comprising twenty-four treatments across three fertility gradient strips for this study. The dependent variable was PHSTVs, while the independent variables included initial soil nutrient status, fertilizer nutrient, along with crop grain yield (GY) or total uptake (TU) of nutrient. Throughout the investigation, multiple linear regression (MLR) models’ were implicated to predicting AN, AP, and AK after individual crop and after whole cropping sequence also. Notably, the MLR models demonstrated improved predictive accuracy for individual crop compared to the entire DSR-W-CS. Additionally, these models exhibited satisfactory precision in predicting post-DSR-W-CS AN, AP, and AK. Following the DSR-wheat sequence, apparent balance of organic carbon (OC), AN, AP, and AK were − 3.28

Zinc (Zn) content in the soils of Western Indo-Gangetic Plain is deficient due to its low application rate and thereby its distribution into different fractions is not proportional. Zn behaves as cation and acts as micronutrient is the common part in all the fractions; thus, its availability merely depends upon the Soil Organic Carbon content (SOC). Thus, understanding of both SOC and Zn dynamics across the soils is crucial for enhancing nutrient availability and soil health with the objectives to evaluate the physio-chemical properties of soil, Zn fractions and its sorption–desorption behaviour, soil carbon pools and its related indices. Potato in this region is the major crop which cultivated either as main crop or secondary crop by most of the farmers. Soil samples were taken from three potato-based cropping systems (viz: sugarcane–ratoon–potato (SRP), paddy–potato (PP) and vegetable–vegetable (VV) along with fallow land considered as reference) at three depths (0–15, 15–30, 30–45 cm) in the western Indo-Gangetic plains. In order to fulfil the objectives, the samples were analysed for physio-chemical properties, SOC pools, its indices, Zn fractions and its sorption–desorption behaviour. Results showed that clay content increased with depth and choked the pores so porosity decreased and chemical activity, electrical conductivity (EC), and pH increased, while SOC and nutrient levels fell significantly in sub-surface soils. At surface, non-labile (NL) and very labile (VL) fractions contributed to about 65