Effects of gypsum, Zn, and intermittent saline irrigation on the growth, yield, and nutrition of rice plants grown in a saline soil

Abstract

A greenhouse experiment was conducted to evaluate the effects of gypsum, Zn, and intermittent saline irrigation on the growth, yield, and nutrition of rice plants grown in a coastal saline soil. Highly significant effects were detected in the treatments with various levels of salinity, gypsum, Zn, and their interactions on the growth, yield, and nutrition of the rice plants. Gypsum and Zn application significantly reduced the adverse effects of salinity and resulted in the production of the maximum number of tillers and in the tallest plant height. Reduction in grain yield was about 70 and 90% for saline irrigation applied at the rate of 8 and 16 mS/cm, respectively compared with tap water irrigation (0.6 mS/cm). The combination of gypsum and Zn produced a grain yield about 30, 8, and 20% higher than that of the control at 0.6, 8, and 16 mS/cm salinity, respectively. Harvest index was reduced due to saline irrigation but gypsum and Zn were found to increase the harvest index of rice. Nitrogen and P contents of straw decreased with the increase in the salinity levels but gypsum and Zn had an additive effect on the N content. The treatments were found to be significant for the K, Ca, Mg, S, Zn, Na, and Cl contents of the rice plant. The Mg content increased up to 8 mS/cm level of salinity. The interactive effects of gypsum and Zn were found to be conducive to the increase of the K, Ca, Mg, S, Zn contents and decrease of the Na and Cl contents of the rice plant even at the highest salinity (16 mS/cm) level. © Taylor & Francis Group, LLC.