Wood Vinegar and Biochar Primed Seeds Improve Rice Cultivation
Introduction
Rice is a staple food for nearly half of the global population, but its traditional cultivation methods demand extensive water and labor resources. Dry direct-seeded rice (dry-DSR) presents a promising alternative, reducing water use and labor input. However, challenges such as poor seedling emergence and weak early growth limit its widespread adoption. A recent study investigated the impact of seed priming with wood vinegar and seed coating with biochar to enhance the establishment and yield of water-saving and drought-resistant rice.
Experimental Design and Application
The study evaluated the effects of wood vinegar and biochar on the dry-DSR rice variety Hanyou 73. Experiments were conducted in growth chambers and field conditions.
- Wood Vinegar Priming: Rice seeds were soaked in different concentrations of wood vinegar solutions (1:10 to 1:400 dilution) to determine the optimal concentration for germination enhancement. The 1:50 dilution was found to be most effective.
- Biochar Coating: Rice straw biochar was applied at varying concentrations (20% to 50%) to determine the best formulation for seed coating. The 20% biochar content yielded the best results.
- Field Trials: Seeds treated with wood vinegar and biochar were compared to untreated controls in randomized field plots. The treatments included wood vinegar priming alone, biochar coating alone, and a combination of both.
Key Findings
- Enhanced Germination and Seedling Growth: Wood vinegar priming at a 1:50 dilution improved final emergence by 58%, while biochar coating at 20% increased emergence by 31%. The combination of both treatments resulted in a 67% higher emergence rate compared to untreated seeds.
- Improved Seedling Biomass: Wood vinegar increased total seedling biomass by 26%, and biochar coating led to a 10% improvement. The combined treatment further enhanced biomass by 31%.
- Higher Grain Yield: Individual applications of wood vinegar and biochar resulted in a 12% and 19% increase in yield, respectively. The combination of both treatments produced a 20% higher grain yield compared to the control.
- Physiological Benefits: The treated plants exhibited improved photosynthetic efficiency, higher chlorophyll content, and greater water-use efficiency.
Implications
The results suggest that wood vinegar priming and biochar coating are effective, eco-friendly methods for enhancing seedling establishment and improving the yield of dry-DSR rice. These treatments offer a viable strategy to mitigate the challenges associated with direct-seeded rice cultivation and could contribute to more sustainable rice production in water-limited environments.