Effect of organic fertilizer application on growth characteristics and saponin content in Codonopsis lanceolata

Organic fertilizers were applied in four different forms: mixed organic matter, fermentation cake, bacterial culture, and rice husks, excluding conventional chemical fertilizer and non-treatment used as control. The results showed that soil pH was acidified after fermentation cake and chemical fertilizer treatment. Specifically, chemical fertilizer treatment showed higher phosphoric-acid content than other treatments, while total N content was higher in fermentation cake, mixed organic matter and chemical fertilizer. Growth of Codonopsis lanceolata showed superior tendency in the treatment of mixed organic matter and fermentation cake. Lancemacides, the major saponin of C. lanceolata, could be identified as foetidissimoside A, lancemaside A, lancemaside B, and lancemaside D. However, among them, quantitative analysis could not be conducted on foetidissimoside A due to its very low content, and lancemaside A was the most abundant saponin in the root from all the treatments. The content of lancemaisde A according to organic fertilizer application showed the highest value of 0.12 mg g−1 in the treatment of mixed organic matter, followed by the fermentation cake, bacterial culture, non-treatment, rice husks and chemical fertilizer, in that order. The content of lancemaside B and D was very low compared to lancemaside A, and there was no difference among treatments. Therefore, it was verified that the growth of C. lanceolata was superior in application of mixed organic matter and fermentation cake, and the major saponin, lancemaside A, was also increased.