Abstract: Through the analysis of the medium and micro elements contents in 30 samples of soil and flue-cured tobacco (Nicotiana tabacum L.) cultivar Honghuadajinyuan collected from Huili tobacco-growing areas of Sichuan Province, this paper studied the quantitative relationships of the elements contents between soil and flue-cured tobacco. In most soils of Huili tobacco-growing areas, the medium and micro elements contents were in suitable range; but in parts of the soils, the contents of water-soluble boron and available zinc were lower. The tobacco leaves had low contents of copper and magnesium. Multiple linear regression analysis showed there were significant relationships of the medium and micro elements contents between soil and tobacco leaves. The Mn and Zn contents in tobacco leaves were significantly affected by the contents of five medium and micro elements in soil, but the Ca content in tobacco leaves was only affected by the DTPA-Mn and exchangeable Ca contents in soil. Partial correlation and path analysis suggested that the micro elements contents in tobacco leaves were positively correlated with the corresponding micro elements contents in soil, and the direct effect coefficient was the maximum. There existed synergistic and antagonistic effects among the medium and micro elements in soil. The contents of all the medium and micro elements in tobacco leaves were most affected by the available Mn content in soil, but the Zn content in tobacco leaves was most affected by the other medium and micro elements in soil.

Key words: Suspending pariculates, Rotifer-culturing pond ecosystem