MITIGATION OF CADMIUM STRESS IN RICE BY EXOGENOUS APPLICATION OF SODIUM NITROPRUSSIDE (NITRIC OXIDE DONOR)

Abstract

A pot experiment with BRRI dhan48 was conducted at the Experimental shed of the Department of Agronomy, Sher-e Bangla Agricultural University, Bangladesh during the summer season (April-August) to investigate the role of exogenous sodium nitroprusside (SNP) in growth and yield of rice under different cadmium stress condition. The experiment was carried out ten cadmium stress treatments viz. control (without cadmium), control+SNP (without cadmium with 0.2 mM SNP), Cd0.5 (0.5 mM CdCl 2 ), Cd0.5+SNP (0.5 mM CdCl 2 with 0.2 mM SNP), Cd1 (1 mM CdCl 2 ), Cd1+SNP (1 mM CdCl 2 with 0.2 mM SNP), Cd1.5 (1.5 mM CdCl 2 ) and Cd1.5+SNP (1.5 mM CdCl 2 with 0.2 mM SNP), Cd2 (2 mM CdCl 2 ) and Cd2+SNP (2 mM CdCl 2 with 0.2 mM SNP). Cadmium stresses significantly reduced the plant height and tillers hill -1 at all growth duration. Leaf relative water content (RWC) and chlorophyll (chl) content also reduced due to cadmium stresses. At harvest, cadmium stresses reduced the effective tillers hill -1 , number of filled grains panicle -1 , 1000-grain weight, grain yield, straw yield and harvest index. On the other hand, exogenous application of sodium nitroprusside (SNP) improved the plant height, effective tillers hill , panicle length, filled grains panicle -1 , 1000-grain weight, straw yield and grain yield upto 1 mM cadmium stress. But SNP application could not improve crop growth parameters, physiological parameters and yield at higher level of cadmium stress (1.5 and 2 mM CdCl 2

) significantly.