Relative Efficiency of Different Crops for their Phyto-extraction Capacity in Managing Heavy Metals Stress

Abstract

A study was undertaken to study the different plant species for their heavy metals removal capacity and suitability for phytoremediation under micro plots (1.5×1.0×0.5 m3) at Anand Agricultural University using factorial completely randomized design with three replications. The soil in bulk having sandy loam texture was collected from mixed industrial effluent irrigated fields and adjoining tube well irrigate fields and utilized in the micro plots. Three levels of irrigation water viz., 100% mixed industrial effluent, 1:1 diluted effluent and tube well water were kept to study their effect on growth and yield of different crops sunflower, cotton, tobacco and castor. Among the crops, the biomass yield of castor was maximum followed by cotton, while minimum yield was recorded in tobacco. The overall findings of the present study indicated that the castor could remove more quantity of total heavy metals (Cd+Ni+Cr+Co+Pb) from contaminated soil in one cropping season than other crops viz., cotton, tobacco and sunflower. However, the extraction efficiency of tobacco for total heavy metals was higher than the other crops for production of unit biomass unit time-1; and followed the ascending order tobacco>sunflower>cotton>castor. The values of accumulation factors confirmed the order of phytoextraction efficiency of the crops. Therefore, the suitable crop needs to be selected for bioremediation of contaminated site depending on the factors like availability of time and economic importance of the crop.