Biochar impact on physiological and biochemical attributes of Spinach (Spinacia oleracea L.) in nickel contaminated soil

Disastrous effect of nickel on spinach was discussed by number of authors but the effect of amendments like biochar with nickel on Spinacea oleraceaL. is not still discussed by any author of the world because biochar was used as soil amendments which play a vital role in reducing mobilization and uptake of nickel by spinach plants. As nickel contaminated plants are very harmful for the consumption by living organisms. Nickel can be gathered in agronomic soils by anthropogenic actions such as Ni-Cd batteries. In this study, the growth, physiological, photosynthetic and biochemical responses of Spinacia oleracea grown in Ni-spiked soil (0, 25, 50 and 100 mg Ni/Kg soil) at three levels of cotton-sticks-derived biochar “CSB” (0, 3 and 5 %) were evaluated. The results exposed significant decrease in growth, photosynthetic, physiological, and biochemical traits of S. oleracea when grown in Ni-polluted soil. However, this decrease was less pronounced in CSB amended soil. A steady rise in the MDA (0.66 µg/g to 2.08 µg g-1), ascorbic acid (1.24 mg/g to 1.57 mg/g)and sugar concentrations (1.73 mg/g to 2.16 mg/g)was observed with increased concentration of Ni. The increasing percentages of CSB from 3 % to 5 % decreased Ni concentrations in root and shoot of experimental plant. Higher production of chlorophyll, amino acids and protein with CSB amendment looked like alleviation in Ni toxicity. Therefore, it is concluded that, Ni toxicity and availability to the plants can be reduced by CSB amendments.