Chemotaxonomic variation in secondary metabolites contents and their correlation between environmental factors in Salvia miltiorrhiza Bunge from natural habitat of China

Phytogeographical variation has an impact on up/down regulation of secondary metabolites in medicinal plants. In this context, present study analyzed the influence of environmental factors on secondary metabolites in Salvia miltiorrhiza from natural habitat of China with different topographical conditions. The chemotypic variation was further correlated with climatic factors than micronutrients in the soil. The data revealed that tanshinones were more likely to be influenced by changes in ecological factors compared with phenolic acids. Tanshinone content was positively correlated with annual sunshine duration (correlation coefficients ranged from 0.379 to 0.730, P < 0.01 or 0.05), but negatively correlated with annual mean temperature (correlation coefficients ranged from - 0.358 to - 0.718, P < 0.01 or 0.05) and annual average precipitation (correlation coefficients ranged from - 0.425 to - 0.679, P < 0.01); the opposite situation was found in salvianolic acid B (correlation coefficients were - 0.137, 0.084, 0.19), caffeic acid (correlation coefficients were - 0.336, 0.246, 0.216, P < 0.05) and rosmarinic acid (correlation coefficients were - 0.518, 0.475, 0.493, P < 0.01). Among the micronutrients, soil concentrations of Ba, Al and Mg exhibit the positive correlation with tanshinone content, but Pb exhibit the negative correlation with tanshinone content. Total N and K presented positive effects on most of phenolic acids. Ba showed significant negative and direct effects on salvianolic acid B (correlation coefficient was - 0.281) and Rosmarinic acid (correlation coefficient was - 0.367, P < 0.05). Therefore, the elite chemotype of S. miltiorrhiza identified among the collected samples express the correlation of phyto-geographical condition on the quantity of industrially viable metabolites, tashinones and phenolic acids. This aids in site specific exploration of high metabolite yielding samples to meet out the commercial demands and, promote the agriculture practices of this industrial crop for societal upliftment in area having similar phytogeographical locations.