The experiment was conducted on three cultivars of canola (Brassica napus L.): Exceed, Cyclone and Legend, with the objective of investigating the alleviation of the rhizospheric lead toxicity by exogenous potassium. Seeds were germinated in pots and when plants were twenty-day-old, lead @15.0 and 30.0mg kg-1 soil was added to pots. Plants were foliar sprayed twice with KCl solution. Plants were arranged in a completely randomized design. Various growth and production parameters were evaluated at physiological maturity. The fresh & dry weight of stems increased by 17.6% and 25.6%, correspondingly, when the plants were treated with KCl as compared to the control, but decreased by 20.4%, and 13.9%, respectively, in plants treated with 15.0mg kg-1 of lead. These reductions in weight were higher under 30.0mg kg-1 of lead applications. Roots (fresh & dry weight) of plants under the dual combination of lead and potassium decreased but this reduction was lower than in plants treated with lead only, which confirmed that potassium alleviated the toxic effect of the lead metal. The seeds (number & total yield) also decreased due to lead toxicity. The seeds (number & total yield) of plants under the dual combination of lead and potassium decreased, but this reduction was lower than in plants treated with lead only, which proved that potassium alleviated the toxic effect of lead.

28.1.2023