AUTHOR=Jian Shao-Fen , Huang Xue-Jing , Yang Xiao-Nan , Zhong Chu , Miao Jian-Hua 

TITLE=Sulfur Regulates the Trade-Off Between Growth and Andrographolide Accumulation via Nitrogen Metabolism in Andrographis paniculata

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.687954

DOI=10.3389/fpls.2021.687954

ISSN=1664-462X

ABSTRACT=<p>Nitrogen (N) and sulfur (S) are essential mineral nutrients for plant growth and metabolism. Here, we investigated their interaction in plant growth and andrographolide accumulation in medicinal plant <italic>Andrographis paniculata</italic> grown at different N (4 and 8 mmol·L<sup>−1</sup>) and S concentration levels (0.1 and 2.4 mmol L<sup>−1</sup>). We found that increasing the S application rate enhanced the accumulation of andrographolide compounds (AGCs) in <italic>A. paniculata</italic>. Simultaneously, salicylic acid (SA) and gibberellic acid 4 (GA<sub>4</sub>) concentrations were increased but trehalose/trehalose 6-phosphate (Tre/Tre6P) concentrations were decreased by high S, suggesting that they were involved in the S-mediated accumulation of AGCs. However, S affected plant growth differentially at different N levels. Metabolite analysis revealed that high S induced increases in the tricarboxylic acid (TCA) cycle and photorespiration under low N conditions, which promoted N assimilation and S metabolism, and simultaneously increased carbohydrate consumption and inhibited plant growth. In contrast, high S reduced N and S concentrations in plants and promoted plant growth under high N conditions. Taken together, the results indicated that increasing the S application rate is an effective strategy to improve AGC accumulation in <italic>A. paniculata</italic>. Nevertheless, the interaction of N and S affected the trade-off between plant growth and AGC accumulation, in which N metabolism plays a key role.</p>