Preparation and Function of Medicine and Fertilizer Integrated Aqua based on Berberine and Biogas Slurry

The objective of our study is to refine the formula and to examine the function of medicine and fertilizer integrated aqua. First, the biogas slurry was purified by mixing with the magnet, gypsum and diatomite. The ratio of mineral nutrients N, P, K were optimized by orthogonal test using the content of water-insoluble as an index, and the optimum formula was combined with berberine to prepare the medicine and fertilizer integrated aqua. The inhibitory effect of this novel medicine and fertilizer integrated aqua on Botrytis cinerea and its impact on the growth of Chinese cabbage were assayed. Results showed that after purification, the concentration of Fe, Mn and Zn elements increased while Cu and other heavy metal ion sharply declined. In the medicine and fertilizer integrated aqua (0.01% berberine, 17% urea, 9% potassium dihydrogen phosphate, 10% potassium nitrate and 8% fulvic acid, followed by a fill-up of biogas slurry), the mass ratio of N:P₂O₅:K₂O was 8.51:4.18:7.87, and the sum of N, P₂O₅ and K₂O means that the nutrient content was 205.6 g/L, which could meet the crop's nutrient needs. The results of antibacterial tests proved that medicine and fertilizer integrated aqua had a strong inhibitory effect on Botrytis cinerea, EC₅₀ could be reduced to 12.12 μg/mL, which was reduced by 3.04% compared with the EC₅₀of the berberine aqua (398.1 μg/mL). The growth of Chinese cabbage was effectively promoted by spraying 150 times diluted medicine and fertilizer integrated aqua (the nutrient content is 1.67 g/L). This study provided a scientific reference for improving antibacterial effect and fertilizer efficiency of biogas slurry and developing medicine fertilizer with biogas slurry and berberine as the main raw material.