Rafa Abid
Bahauddin Zakariya University, Pakistan
Title: Innate variability of biofuel/bioenergy tree species at an early establishment under metal toxicity in arid environmental conditions
Biography
Biography: Rafa Abid
Abstract
Bioaccumulation of heavy metals in agricultural soil is a serious environmental concern throughout the world. In order to clean up environment, metal sequestration using different plant species has gained considerable attention. One year old sapling of two native biofuel tree species Jatropha curcas L and Pongamia pinnata L, were exposed for 12 months under metal contaminated soil irrigated with textile industry effluent. Prior to application, the effluent was appraised for its physico-chemical analysis. The treatments comprised of T1 (20 ml L-1) and T2 (40 ml L-1) while T0 (control plants) were spiked with tap water. The effluent contained metals in amounts; lead (Pb 42 mg L-1), cadmium (Cd 0.33 mg L-1), arsenic (As 48 µg L-1), total chromium (Cr 41 mg L-1), chromite (CrIII 39 mg L-1) and chromate (CrVI 3 mg L-1). These levels were greater than permissible limits reported by USEPA (0.015 mg L-1 Pb, 0.005 mg L-1 Cd, 10 µg L-1 As and 0.1 mg L-1 Cr). Based on metal accumulation, J. curcas exhibited (P≤0.05) more ability to accumulate (Pb, Cd, As, Cr) in aboveground tissues than roots while more Zn in root than shoots. Memebrane injury index (%) was greater in roots (114%) than (95%) leaves and evans blue dye root uptake was also found higher in P.pinnata (0.92 A600nm) than J.curcas (0.42 A600nm) at elevated effluent level.Thus the two species exhibited differential response for their metal tolerance strategy. Being biodiesel/bioenergy plants and non-food specices, both tree species may be used to clean up metal-contaminated soils.