Chin J Plant Ecol ›› 2009, Vol. 33 ›› Issue (5): 885-892.DOI: 10.3773/j.issn.1005-264x.2009.05.007

• Research Articles • Previous Articles     Next Articles

EFFECTS OF NITROGEN AVAILABILITY IN SOIL ON THE CONTENTS OF FLAVONOIDS AND CAFFEATES IN A MEDICINAL PLANT, ERIGERON BREVISCAPUS

SU Wen-Hua*(), ZHANG Guang-Fei, ZHOU Hong, ZHANG Ya-Ni   

  1. Institute of Ecology and Geobotany, Yunnan University, Kunming 650091, China
  • Received:2008-11-13 Revised:2009-05-18 Online:2009-11-13 Published:2009-09-30
  • Contact: SU Wen-Hua

Abstract:

Aims Our objectives are to explore the effect of nitrogen availability in soil on the accumulation of the secondary metabolites of plants growing in different areas, to test the C/N hypothesis, and to address reasons for the variability of content of active constituents in medicinal herbs growing in different areas.
Methods We surveyed plants and soils in 44 populations of a medicinal plant, Erigeron breviscapus. We analyzed total and active nitrogen of soil samples and total flavonoids, scutellarin, caffeates and nitrogen in plant samples. Linear regression analysis was used to study relationships between soil nitrogen availability and active constituents of plants.
Important findings The contents of flavonoids and caffeates in plants were negatively correlated with soil nitrogen availability and plant nitrogen content, as predicted by the carbon/nutrient balance hypothesis. Variation in available soil nitrogen accounted for 17%-30% of the variation in the content of secondary metabolites of plants. In contrast, variation in available nitrogen accounted for about 80% of the variation in content of total flavonoids in the rendizina and about 60% of content of scutellarin and caffeates in the non-rendizina. It appeared that effects of nitrogen availability on the accumulation of secondary metabolites in the plant were affected by other factors, such as genetic and environmental variation. The content of flavonoids and caffeates in plants growing in different areas varied with differences in nitrogen availability, ecological factors and genotypes.

Key words: Erigeron breviscapus, soil nitrogen, secondary metabolite, flavonoids, caffeates