Enhanced seed quality and physio-biochemical parameters in lentil through biochar and humic acid- based seed priming

Lentil (Lens culinaris Medik.) is a nutritionally valuable pulse crop that enhances food security and soil fertility through biological nitrogen fixation. However, its productivity is often constrained by poor germination and uneven seedling establishment. This study investigated biochar and humic acid as sustainable seed-priming agents to improve lentil seed performance. After preliminary optimization, the most effective concentrations of both agents were evaluated under controlled laboratory conditions. Germination percentage, seedling length, vigour indices, chlorophyll content, and oxidative stress response (DAB assay) were assessed. Both treatments significantly enhanced seed and seedling traits compared with unprimed controls (p < 0.05). Biochar priming increased germination by 14.7%, seedling length by 26.3%, and vigour index by 32.5% over control, alongside higher chlorophyll content and reduced hydrogen peroxide accumulation, indicating improved physiological efficiency and stress mitigation. Humic acid also improved performance, though to a lesser degree. The results demonstrate that biochar and humic acid priming enhance seed vigour and metabolic activity by promoting stress regulation and efficient energy utilization. Overall, biochar emerged as the superior and eco-friendly option for improving germination and early growth in lentil, offering a practical approach for sustainable pulse production and climate-resilient agriculture.