Optimizing wood vinegar as an industrial product for sustainable agriculture: A global meta-analysis of its potential for crop production

Wood vinegar (WV), an industrial product derived from biomass pyrolysis, holds significant potential for sustainable crop production. However, a systematic and quantitative assessment of its effects on crop yield across different species, application methods, and environmental conditions has been lacking. Here we present a global meta-analysis based on 94 studies to comprehensively evaluate the impacts of WV on crop seed germination, physiological traits, and yield, and to identify key factors modulating these effects. Our results showed that WV promotes germination in a concentration-dependent manner. At 0.5–1.0%, it increased germination by 31.5% in monocots, while at 0.1–0.5% concentration, it increased germination rate by 25.6% in dicots, without inhibiting subsequent seedling growth. For yield, foliar spray and soil application increased crop yield by 19.4% and 17.8% on average. Application strategies must be optimized by crop type. For foliar spray, monocots require multiple applications at concentrations ≤ 0.5%, whereas dicots benefit from fewer applications within the optimal range of 0.1–0.5%. For soil application, limited additions at 0.5–1.0% achieve the best balance between yield benefit and cost for dicots. WV produced at low pyrolysis temperatures (≤ 500 ° C) is more effective for foliar use, while low-pH (≤ 4) WV is preferable for soil application. Foliar application performed better under high soil nutrient conditions, and soil application was more effective in soils with pH > 7. Correlation analyses indicate that yield enhancement is closely associated with increased antioxidant enzyme activity in leaves and improved photosynthetic parameters. This study provides global-scale quantitative evidence supporting WV as an industrial biostimulant with strong potential to enhance crop production sustainably, and offers specific parameter thresholds and theoretical guidance for its precise application across diverse crop types and soil conditions.