Author : Saw Hto Lwe Htoo

Summary : The morpho-physiological and phytochemical responses of Centella asiatica to arbuscular mycorrhizal fungi (AMF) inoculation, organic soil amendments and Pb were evaluated in this study. Colonization of AMF in C. asiatica was monitored using Mykovam and MykoPlus biofertilizers. Colonization started within two weeks after planting, with greater colonization by Mykovam. AMF had no interaction with both soil amendments and Pb contamination, and separately affected C. asiatica. Soil amendments (plant-based compost, vermicompost, urea) increased the vegetative and reproductive characters and biomass production in the presence of AMF and also influenced N, P and K content, antioxidant activity and phytochemical production. AMF increased the growth of the plant but it did not affect N, P, K and phytochemical content. Vermicompost was the best organic soil amendment among the treatments. N was found essential for antioxidant activity and phytochemical production. Pb contamination (0, 250, 500 mg kg-1) did not influence plant growth in the presence of AMF. Pb significantly decreased root length by 15% at 500 mg kg-1 AMF did not show significant effect in the presence of Pb contamination except for advancing flowering time and slightly increasing antioxidant activity. C. asiatica was found tolerant to Pb up to 500 mg kg-1 Pb distribution in the plant occurred as follows: leaves (42%), roots (38%) and stem (20%). Pb accumulation (0.26 µg/g) in the edible part of the plant was below the permissible level of Codex Alimentarius (0.05 - 0.3 µg/g) and World Health Organization (WHO) (10 µg/g).