Improvement of yield and quality of chinese cabbage (brassica rapa pekinensis l.) by augmenting soil fertility, nutrient status, and microbial activity with biogas slurry application

In order to provide experimental basis for the optimal application of biogas slurry in field conditions, this study was conducted to investigate the effect of different doses of biogas slurry (return to the field) on soil fertility and crop production (Chinese cabbage) from China. The experiment was conducted in 7 different groups (with 3 replicates each) using nitrogen equivalent chemical fertilizer (CF) and nitrogen equivalent biogas slurry (BGS) as the base fertilizer and four topdressing treatments including (1) NF (2) 100% CF (3) 50% BGS with 50% CF (4) 100% BGS (5) 200% BGS (6) 300% BGS (7) 400% BGS. The results showed that with increasing BGS dosage during all growth phases of Chinese cabbage, soil fertility increases linearly with significantly higher soil organic matter, soil enzymes (sucrose, alkaline phosphatase, and catalase) and nutrients (N, P, K, and ferrous ion) status. These impacts of BGS treated soils have been translated to the significant improvement in yield and quality of cabbage. After comprehensive analysis, it has been concluded that the soil amended with 200% BGS (treatment 5) was suitable to meet the nutrient requirements for optimal plant growth and development that leads to high quality and maximum yield of Chinese cabbage.