Effect of edaphic factors on phenolic contents in the natural population of Ichnocarpus frutescens (L.) R.Br. collected from Central India and Eastern Ghats

Ichnocarpus frutescens, commonly known as "Black creepers" is distributed in diverse phytogeographical regions of India. In this study, we examined the significance of edaphic factors in the variation of phenolic contents of I. frutescens collected from different regions. Among the twenty-one germplasms, NBI-28 from Tamia (Madhya Pradesh) exhibited high levels of gallic acid (0.32%), caffeic acid (0.65%), vanillic acid (0.27%), vanillin (0.09%) and ferulic acid (0.038%). The highest concentrations of nitrogen, potassium and phosphorus were observed in NBI-29 (0.079%), NBI-27 (0.019%) and NBI-36 (0.004%) respectively. The highest values for electrical conductivity (E.C.), pH and organic carbon (O.C.) were observed in NBI-26 (0.317 ds/m), NBI-04 (7.6), and NBI-29 (11.59%), respectively. Organic carbon and phosphorus showed a significant correlation with ferulic acid (r = 0.54) and protocatechic acid (r = 0.62) respectively. Furthermore, samples differ significantly in terms of nitrogen, phosphorus, potassium, pH, organic carbon and electrical conductivity. This study suggest that, the productivity of secondary metabolites of I. frutescens were affected by various edaphic factors. However, the role of other environmental factors need to be investigated.