Abstract
The effects of different levels(ECiw=0.60, 8,16 dSm-1)of water salinity, gypsum(G= 0.160kg ha-1) and Zinc(Zn=0, 5kg ha-1)on the concentration and uptake of nutrients by rice roots and quality of rice grains were studied in greenhouse. Highly significant(P^0.01)effect of salinity on the concentration and uptake of nutrients by roots and quality of rice grains was found, the adverse effect being more pronounced on BR 6 rice while the exotic CSR 4 appeared more salt tolerant. The concentration and uptake of Ca, Mg and Zn in roots decreased with an increase in salinity. The concentration of Na, Cl and S increased with an increase in water salinity but the uptake of S and Cl was slightly decreased at 8 dSm-1 while 50 per cent yield reduction was at 16 dSm-1. Maximum amount of uptake of Na was at 8 dSm-1 followed by that at 16 and 0.60 dSm-1 for both the cultivars. Application of gypsum and Zn at the rates of 160 and 5kg ha-1 increased the concentration and uptake of Ca, Mg and S, and were effective to decrease the concentration of Na and Cl in rice roots. Salinity significantly reduced the grains and root yields of the rices but GiM and Zn5 had favorable effects on these parameters. Protein contents of the rices varied significantly with the treatments and ranged from 68.8 to 87.5 g kg-1 for CSR 4 and 67.5 to 82.5 g kg-1 for BR 6. Application of G160 and Zn5 separately or in combination improved the protein contents of rice grains, regardless of salinity.
