Effect of soil salinity and zinc application on electrochemical and chemical kinetics and growth and yield of rice
Verma, T.S.; Neue, H.U.
Communications in Soil Science and Plant Analysis 15(5): 553-571
An experiment was conducted with 3 levels of soil salinity (ECe [electrical conductivity] 2.5, 5.6 and 8.7), 3 levels of Zn (0, 10 and 20 mg Zn/kg soil), and 2 rices (experimental line IR10198-66-2 and cv. IR28). The soil solution concentrations of NH4+, P, K+, Ca2+, Mg2+, Na+, Fe2+, Mn2+ and Zn2+ increased with salinity level until the 10th wk of submergence. Increasing the levels of salinity also increased the values of soil solution EC but decreased those of pH and Eh [oxidation reduction potential]. Zn application decreased the concentrations of P, K+, Ca2+, Mg2+, Na+, Fe2+ and Mn2+; increased the concentration of Zn2+; and had no effect on NH4+ and pH and Eh in the soil solutions throughout the experiment. Almost all the nutrients increased during the first 5 wk of submergence and then decreased to a fairly constant value. The yield and yield-contributing characters in IR28 decreased linearly and significantly with an increase in soil salinity level. In experimental line IR10198-66-2, these plant characters decreased only at the highest level of soil salinity (ECe 8.7). Zn applications of up to 10 mg/kg soil increased the yield and yield-contributing characters in IR28 and had no effect on IR10198-66-2.