اثر شور و غرقاب شدن خاک بر غلظت برخی عناصر پرمصرف و سدیم در بخش هوایی ذرت

Salinity and waterlogging are two important abiotic stresses limiting plants growth and yield in the world. in this research, the effects of soil salinity and waterlogging on the concentrations of calcium (ca), potassium (k), magnesium (mg) and sodium (na) in forage corn (zea mays cv. single cross 704) shoot were studied under greenhouse conditions. a factorial experiment with two factors was performed on the basis of completely randomized design with three replications. the studied factors were: waterlogging duration in five levels (0, 2, 4, 8, 20 days) and saturated soil extract salinity in four levels (0.11, 2, 4, 8 ds/m). a loamy sand soil for plant growth substrate and nacl salt for establishing the levels of salinity were used. the salinity and waterlogging factors were imposed simultaneously from the five-leaf stage of plant growth period. the plants were harvested 60 days after sowing and the concentrations of ca, k, mg and na in corn shoot were determined by dry ashing method. the results showed that by increasing the level of salinity, the concentrations of k, ca and mg in corn shoot were decreased significantly but the na concentration of shoot was increased significantly. by increasing the duration of soil waterlogging, the ca concentration of shoot was decreased significantly, while the k, mg and na concentrations of shoot were increased significantly. however, the effect of salinity on the ca, k, mg and na concentrations of shoot was dependent on the duration of soil waterlogging. the k, ca, and mg concentrations of corn shoot were greater than those of its root (3.72, 3.17 and 1.69 times, respectively), while the na concentration of corn root was 1.52 times greater than that of its shoot. the results demonstrated that even short periods of soil waterlogging had considerable long-term effects on the ca, k, mg and na concentrations of forage corn shoot under saline and non-saline conditions.