Physiological and biochemical response of finger millet plants exposed to arsenic and nickel stress

Heavy metal stress is one of the major abiotic stresses that affects growth, development and yield in cereals. This investigation was conducted to examine the toxic effects of arsenic (As), nickel (Ni) and arsenic + nickel (As + Ni) on finger millet seedlings. The experiment involves exposing fourteen-day-old finger millet plants to various concentrations of As (10, 25, 50 and 100 mu M), Ni (100, 250, 500 and 1000 mu M) and As + Ni (10 + 100, 25 + 250, 50 + 500 and 100 + 1000 mu M). The presence of heavy metals (HMs) led to oxidative stress and decreased root and shoot length, biomass, total chlorophyll, and leaf relative water content (LRWC). In addition, the levels of electrolyte leakage (EL), proline, H2O2, and MDA content increased significantly at higher concentrations of HMs (As >50 mu M, Ni >500 mu M and As + Ni >50 + 500 mu M). An increased accumulation of As and Ni was found in roots compared to shoots. This is the first report to identify the physiological and biochemical responses of finger millet plants exposed to Arsenic and Arsenic + Nickel combined stress.