Interactive effects of cadmium and salinity stresses on growth and cadmium, sodium and potassium accumulation in two hybrid maize varieties

This study was carried out to determine the effects of cadmium (Cd) (0 and 2 mg kg-1 soil) and salt stress (NaCl 0 and 3000 mg kg-1 soil) on shoot dry weights and shoot Cd, sodium (Na) and potassium (K) concentrations of salt-tolerant (Maverik) and salt-sensitive (RX-9292) hybrid maize varieties. Plants were grown under controlled greenhouse conditions for 19 days. Shoot dry matter productions and shoot Cd, Na and K concentrations were determined following the harvest. Element contents were calculated by multiplying shoot dry weights with element concentrations. Cadmium, NaCl and Cd+NaCl treatments significantly decreased (P < 0.05) shoot dry matter productions of both varieties. The decline in dry matter production was higher in RX-9292 compared to Maverik. Higher increases in Cd concentrations and contents with Cd treatments were observed in RX-9292 than that of Maverik. Combined treatments of Cd and NaCl also yielded higher Cd concentration and contents in RX-9292 compared with Maverik. The variety of RX-9292 had higher Na concentration and content than Maverik under NaCl and Cd+NaCl treatments. Cd-induced growth decline and Cd accumulations in shoots revealed that salt-sensitive RX-9292 was more sensitive to Cd compared to the salt-tolerant Maverik. Plant tolerance of Cd and salinity should definitely be known in cultural practices carried out over agricultural lands with salinity and Cd concerns.