Vermicompost as a Bio-Modulator for Soil and Plant Health: A Systematic Review of Its Role in Biodiversity Conservation and Agricultural Sustainability

Introduction: The intensification of agriculture has contributed to widespread soil degradation and biodiversity loss. While vermicompost has been proposed as a sustainable alternative, existing literature lacks a comprehensive synthesis of its potential as a soil and plant bio-modulator across varied agricultural contexts. This review addresses this gap by providing a rigorous synthesis of the evidence base for vermicompost application.

Methods: Following PRISMA 2020 guidelines, we conducted a systematic search of Web of Science, Scopus, PubMed, and Google Scholar for peer-reviewed studies published between 2000 and 2025. Studies were included if they: (1) evaluated vermicompost effects on soil properties, plant growth, or stress tolerance; (2) reported quantitative outcomes; and (3) were published in English. Fifty studies met our inclusion criteria. A meta-analysis was not performed due to considerable heterogeneity in experimental designs, application rates, and measured outcomes across the included studies.

Results: Across the reviewed studies, vermicompost was consistently reported to enhance soil physical properties including; improved structure, porosity, water-holding capacity, alongside chemical improvements in organic carbon, nitrogen, phosphorus, potassium, and micronutrient availability. Biological activity, including microbial biomass, diversity, and enzymatic function, was also enhanced in vermicompost amended soils. Under drought stress, the studies reported mean biomass increases of 14–37% for wheat due to application of vermicompost 6–8 t ha⁻¹, with corresponding increases in antioxidant enzyme activities (SOD, POD, CAT) ranging from 8–50%. In saline conditions, vermicompost was associated with reduced sodium accumulation and improved K⁺/Na⁺ and Ca²⁺/Na⁺ ratios. Disease suppression, reported across multiple pathosystems, ranged from 40–80%, mediated through competition, antibiosis, hyperparasitism, and induced systemic resistance. However, the magnitude of these effects varied considerably across studies, reflecting differences in vermicompost feedstock, application rates, and environmental conditions.

Conclusions: The existing literature supports vermicompost as a promising soil amendment and fertilizer component for enhancing agricultural productivity and ecosystem resilience while reducing dependency on chemical inputs. Contributions to biodiversity conservation through improved soil biological activity, carbon sequestration, and reduced use of agrochemical. However, variability in feedstock quality and application protocols underscores the need for continued research to optimize its use across diverse cropping systems and environmental contexts.