RESUMO
Objective: To study the effect of applying diammonium phosphate on the yield and quality of Corydalis yanhusuo. Methods: By designing different gradient diammonium phosphate amount, the main growth indicators at different fertilizer amount were observed and recorded under the same planting condition. The contents of total ash, alcohol soluble extract, and tetrahydropalmatine were measured and analyzed after harvest according to the requirement of 2015 edition Pharmacopeia. Results: The tubers growth of C. yanhusuo was the most flourishing with the highest drying rate of 33.7% at diammonium phosphate application amount of 375 kg/hm2. Tuber diameter was the largest (2.57 cm), the fresh yield was the highest (5 482.2 kg/hm2), and the yield was increased to 38.2% than that without fertilizer cultivation. The content of total ash (3.0%) was the lowest. The contents of alcohol soluble extract and tetrahydropalmatine were 24.8% and 0.128%, respectively. Conclusion: Applying diammonium phosphate could increase the yield and quality of C. yanhusuo.