Comparative evaluation of copper, cobalt, cadmium and iron scavenging efficiency by in-vivo and in-vitro grown Momordica charantia using atomic absorption spectroscopy

Phytoextraction, the use of hyperaccumulator plant species to scavenge toxic heavy metals from contaminated soils are considered as an emerging technique for cost effective and environment friendly detoxification. The present study was conducted to evaluate and compare the scavenging efficiency of in-vivo and in-vitro grown Momordica charantia for the uptake of copper , cobalt, cadmium and iron using atomic absorption spectroscopy (AAS). In-vitro plants were cultured on a mixture of 2,4D (2.5 mg/L) and NAA (2.0 mg/L) in MS basal medium. Bioassays of in-vitro and field grown (In-vivo ) M. charantia plants were subjected to atomic absorption spectrophotometer for the analysis of scavenging efficiency of the aforementioned four elements, after a 30 days of growth in soils, contaminated with each of these, separately. The in-vitro M. charantia absorbed much lesser amounts, that is, 0.79, 1.05, 0.45 and 1.61 ppm as compared to field grown plants which showed higher ranges of uptake, that is, 2.09, 10.39, 4.77 and 8.29 ppm for Cu, Co, Cd and Fe, respectively. The metal uptake ratios were proportional to their concentrations in the contaminated soils. Maximum uptake for all the four heavy metals was observed by the roots in all plants, due to localization of their ions in the apoplasm. Nodes also showed high heavy metal accumulation in the aerial region of the plant exhibiting their role during xylem-phloem transportation. Higher concentration of heavy metals in the soil showed a negative effect on their growth.