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Agriculture in the 21st century faces grave challenges to meet the unprecedented food demand of the burgeoning population as well as reduce the ecological footprint for achieving sustainable development goals. The extensive use of harsh synthetic surfactants in pesticides and the agrochemical industry has substantial adverse impacts on the soil and environment due to their toxic and non-biodegradable nature. Biosurfactants derived from plant, animal, and microbial sources can be an eco-friendly alternative to chemical surfactants. Microbes producing biosurfactants play a noteworthy role in biofilm formation, plant pathogen elimination, biodegradation, bioremediation, improving nutrient bioavailability, and can thrive well under stressful environments. Microbial biosurfactants are well suited for heavy metal and organic contaminants remediation in agricultural soil due to their low toxicity, high activity at fluctuating temperatures, biodegradability, and stability over a wide array of environmental conditions. This green technology will improve the agricultural soil quality by increasing the soil flushing efficiency, mobilization, and solubilization of nutrients by forming metal-biosurfactant complexes, and through the dissemination of complex nutrients. Such characteristics help it to play a pivotal role in environmental sustainability in the foreseeable future, which is required to increase the viability of biosurfactants for extensive commercial uses, making them accessible, affordable, and economically sustainable., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

Present study is a maiden attempt to assess net ecosystem exchange (NEE) of carbon dioxide (CO 2 ) flux from jute crop (Corchorus olitorius L.) in the Indo-Gangetic plain by using open-path eddy covariance (EC) technique. Diurnal variations of NEE were strongly influenced by growth stages of jute crop. Daytime peak NEE varied from - 5 µmol m -2  s -1 (in germination stage) to - 23 µmol m -2  s -1 (in fibre development stage). The ecosystem was net CO 2 source during nighttime with an average NEE value of 5-8 μmol m -2  s -1 . Combining both daytime and nighttime CO 2 fluxes, jute ecosystem was found to be a net CO 2 sink on a daily basis except the initial 9 days from date of sowing. Seasonal and growth stage-wise NEEs were computed, and the seasonal total NEE over the jute season was found to be - 268.5 gC m -2  (i.e. 10.3 t CO 2 ha -1 ). In different jute growth stages, diurnal variations of NEE were strongly correlated (R 2  > 0.9) with photosynthetic photon flux density (PPFD). Ecosystem level photosynthetic efficiency parameters were estimated at each growth stage of jute crop using the Michaelis-Menten equation. The maximum values of photosynthetic capacity (P max , 63.3 ± 1.15 µmol CO 2 m -2  s -1 ) and apparent quantum yield (α, 0.072 ± 0.0045 µmol CO 2 µmol photon -1 ) were observed during the active vegetative stage, and the fibre development stage, respectively. Results of the present study would significantly contribute to understanding of the carbon flux from the Indian agro-ecosystems, which otherwise are very sparse., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Production of quality jute fibre primarily depends on the retting process of jute. However, the quality of retting water is of great concern because of the scarcity of available water bodies for retting. A study conducted on physico-chemical and microbiological changes in retting water (pre- and post-retting) from four intensively jute-growing districts namely Nadia, North 24 Parganas, Hooghly and South Dinajpur of West Bengal, India, during jute retting. The post-retting water samples recorded lower pH (6.22 to 7.08) and higher EC (electrical conductivity) (0.509 to 0.850 ds/m) compared with pre-retting water samples (pH 6.63 to 7.44; EC 0.197 to 0.330 ds/m) collected from all the four districts under study. The biological oxygen demand (BOD) and chemical oxygen demand (COD) increased several folds in the post-retting water samples indicating very high microbial growth and activities and depleted oxygen level compared with pre-retting water. The Ca + Mg (calcium + magnesium) content in pre-retting water was high (24.15 to 36.60 ppm) which raised further (61.30 to 103.67 ppm) in post-retting water, while the bicarbonate content also increased and ranged between 2.72 and 6.81 me/l in post-retting water compared with its status in pre-retting water (1.30 to 3.15 me/l). The post-retting water was found to be a rich source of nutrients like nitrogen (N), phosphorus (P), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) which increased substantially because of jute retting as compared with their status in pre-retting water. The population of pectinolytic, xylanolytic, cellulolytic and ligninolytic bacterial cfu (colony forming unit) increased by 1.5 times in post-retting water as compared with pre-retting water, because these specific bacterial population were involved in the degradation of pectin, xylan, cellulose and lignin during retting of jute. Thus, post-retting water can be judiciously used as a potent source of primary, secondary and micronutrients for succeeding crops besides having higher BOD and COD as a result of higher microbial growth related to jute retting.