Journal of Agriculture and Ecology Research International

Green Technologies for Wastewater Treatment: A Critical Narrative Review of Biological, Bio-derived and Hybrid Approaches and Their Translation to Practice

Ritesh Jain — 2026-07-28

Conventional activated-sludge treatment remains energy-intensive, chemically demanding and poorly suited to the recovery of the water, nutrients and energy that wastewater contains. Interest has consequently shifted towards green technologies that treat wastewater through biological, bio-derived or low-input physicochemical processes while lowering carbon and chemical footprints. This critical narrative review examines the principal families of such technologies, namely constructed wetlands and related nature-based systems, phytoremediation with aquatic macrophytes, microalgal and algal–bacterial processes, bioelectrochemical systems, bio-derived adsorbents such as biochar and biosorbents, green-synthesised nanomaterials and solar-driven photocatalysis, and green-oriented bioreactor and electrochemical configurations, before considering how these approaches support resource recovery within a circular-economy framing. Evidence was drawn from scholarly indexes and citation searching, appraised for methodological adequacy, and synthesised thematically rather than catalogued study by study. The available evidence indicates that several green technologies achieve treatment performance approaching or matching conventional processes for specific pollutants, particularly organic matter, nutrients and selected dyes and metals, while offering co-benefits in energy demand, sludge production and resource recovery. Confidence in these conclusions is nonetheless constrained by a predominance of laboratory and short-term studies, uneven geographical representation, inconsistent reporting of operating conditions, and limited long-term field validation. Reported performance varies widely with feedstock, climate and reactor configuration, and mechanistic plausibility has frequently outpaced demonstrated field effectiveness. The synthesis identifies scale-up reliability, standardised performance reporting, life-cycle and techno-economic assessment, and integration into hybrid treatment trains as the most pressing priorities. Green technologies are best understood not as uniform replacements for established infrastructure but as context-dependent components whose value depends on matching process to wastewater type, local conditions and recovery objectives.

Physiological Quality of Strawberry (Fragaria vesca L.) Seeds Subjected to Water Stress

Rodrigo Silva Barbosa — 2026-07-28

Water availability is a key determinant of seed germination and early seedling establishment, whereas water deficit restricts imbibition and delays the metabolic processes required for successful germination. This study evaluated the physiological quality of strawberry (Fragaria vesca L.) cv. Sensação seeds subjected to polyethylene glycol (PEG 6000)-induced water stress. Seeds were exposed to osmotic potentials of 0.0, −0.1, −0.2, −0.3, and −0.4 MPa under controlled laboratory conditions in a completely randomised design with four replicates of 50 seeds. Germination, first germination count, germination speed index, root length, and shoot length were evaluated. Water stress markedly reduced the first germination count, with a significant decline observed as early as −0.1 MPa, indicating that early seed vigour was impaired even under moderate osmotic restriction. In contrast, final germination, germination speed index, and shoot length were not significantly affected within the tested range. Root length showed a decreasing trend with increasing stress intensity, although this response should be interpreted cautiously because it was not consistently supported by both parametric and non-parametric analyses. Overall, the results indicate that the first germination count was the most sensitive indicator of PEG-induced water stress in strawberry seeds, demonstrating that early vigour is affected before final germination capacity is substantially compromised under the evaluated conditions.

Native Plant Diversity and Livelihood Services in Functioning Agroforestry Systems of the Western Himalayan Foothills

Ruchika Langthasa — 2026-07-28

Agroforestry may support native biodiversity and rural livelihoods, but integrated evidence from functioning systems in the western Himalayan foothills remains limited. This study assessed native tree diversity, vegetation structure, ecosystem services, and livelihood contributions in agroforestry systems in Dunga, Thano, and Chandrabani villages of Uttarakhand, India. Vegetation was evaluated using phytosociological attributes, the Importance Value Index, diversity indices, and rank–abundance patterns, while socio-economic information was obtained from 30 households. Dunga and Thano agroforestry systems each contained 10 tree species and recorded Shannon diversity values of 2.092 and 2.087, respectively. Chandrabani contained seven species and had a Shannon diversity value of 1.729. The adjoining pure forest stands showed lower Shannon diversity values of 1.368 and 1.495 and were strongly dominated by Shorea robusta. Rank–abundance patterns indicated a more even distribution of species in the agroforestry systems. Households reported fuelwood, fodder, fruit, soil-conservation, shade, and microclimate-regulation services, although the reported levels varied among villages. Multiple regression analysis explained 54.2% of the variation in annual household income. Dependency score was positively associated with income, whereas forest dependency and family size were negatively associated with income. These findings indicate that diversified agroforestry systems can contribute to native plant conservation and locally important livelihood services, although the limited sampling design restricts wider generalisation.

Genetic Variability, Character Association, Path Coefficient and Genetic Divergence Analysis in Foxtail Millet (Setaria italica L. Beauv) Genotypes

Tauheed Ali — 2026-07-31

The present investigation was conducted to evaluate genetic variability, character association, path coefficient analysis and genetic divergence among eight foxtail millet (Setaria italica L.) genotypes, including one check variety. The experiment was conducted in a randomised block design (RBD) with three replications during the rabi season. Observations were recorded for twenty-five quantitative traits, including plant height, leaf length, leaf width, panicle length, peduncle length, stem diameter, leaf area index, days to 50% flowering, days to maturity, panicle weight, biological yield, harvest index and seed yield per plant. Analysis of variance revealed significant differences among the genotypes for all the characters studied, indicating substantial genetic variability. High heritability coupled with high genetic advance as a percentage of the mean was observed for leaf area index at 30 DAS (78.57% and 228.57%), leaf area index at 90 DAS (66.67% and 157.39%), stem diameter at 30 DAS (73.19% and 123.52%), stem diameter at 60 DAS (67.15% and 105.86%) and seed yield per plant (79.98% and 29.38%), suggesting the predominance of additive gene action and the potential effectiveness of selection for these traits. Seed yield per plant was positively associated with harvest index, panicle length at 60 DAS, leaf area index at 30 DAS and panicle weight at the genotypic level. Path coefficient and genetic divergence analyses were undertaken to assess direct trait effects and diversity, respectively. Among the evaluated genotypes, K4 (V7) recorded the highest seed yield per plant (7.34 g), whereas GPL-11 (V3) exhibited the highest panicle weight (15.00 g). These genotypes may therefore constitute useful genetic resources for breeding programmes aimed at developing high-yielding foxtail millet cultivars.