Study on correlation between volatile oil and rhizosphere soil from roots of Saposhnikovia divaricata / 中草药

ABSTRACT

Objective: To study the correlation between the content of volatile oil and the rhizosphere soil from the roots of Saposhnikovia divaricata collected from different regions at different harvest time. Methods: The volatile oil from the roots of S. divaricata was extracted by steam distillation and analyzed. According to the National Standard of the People's Republic of China, we determined the pH value, total nitrogen, hydrolysable nitrogen, available phosphorus, available potassium, and organic matter in the rhizosphere soil of S. divaricata. The obtained data were statistically analyzed with SPSS 13.0 software. Results: The content of volatile oil in the roots of S. divaricata presented a trend of decrease with different collection regions from south to north and the main chemical components were significantly different, in which 1-(1-formylethyl)-4-(1-buten-3-yl)-benzene and β-bisabolene were found as the principal components. There was a significantly negative power function relationship between the content of volatile oil and the total nitrogen, a significantly non-linear correlation between the content of volatile oil and the hydrolysable nitrogen, but a good correlation between content of volatile oil and available phosphorus, available potassium, and the content of organic matter was found only in the first sample. There were significant good correlations of the pH value and hydrolysable nitrogen with available phosphorus, hydrolysable nitrogen, and available phosphorus with available potassium, hydrolysable nitrogen, available phosphorus, and available potassium with organic matter in rhizosphere soil (P < 0.01). The significant correlation of hydrolysable nitrogen, available potassium with pH was found (P < 0.05). Conclusion: There is no significant difference among the contents of volatile oil extracted from S. divaricata collected at different harvest time. There is a negative correlation between the total nitrogen content in rhizosphere soil and the content of volatile oil, namely, the productivity of volatile oil decreases with the increase of total nitrogen content, while the optimal contents of hydrolysable nitrogen, available phosphorus, available potassium, and organic matter could accumulate the content of volatile oil. On the other hand, pH value may affect the content of volatile oil by modulating the other chemical properties of the rhizosphere soil.