Optimizing soil fertility and pH to maximize cadmium removed by Indian mustard from contaminated soils

The effects of soil pH, different levels of nitrogen (N), phosphorus (P), and potassium (K), alone and in combination on cadmium (Cd) uptake by Indian mustard [Brassica juncea (L.) Czen., cv '426308'] were studied under greenhouse conditions. Results showed that Cd concentration in aboveground biomass at soil pH 5.5 was three times more than at pH 6.5 and 7.5. Treatments without N application at pH 5.5 had the highest Cd concentrations in the aboveground biomass. Dry weight of aboveground biomass was significantly lower at pH 5.5 compared to pH 6.5 and 7.5. Total Cd uptake at pH 6.5 increased by 2 to 2.5 times compared to uptake at soil pH 5.5. Those conditions for maximum Cd accumulation by the aboveground biomass of Indian mustard from Cd-contaminated soil occurs at soil pH 6.5 and when the application rates of N, P, and K are at 200, 100, and 66 kg ha(-1), respectively.