RESPONSES OF FOUR SUBMERGENCE TOLERANT RICE VARIETIES TO DIFFERENT SUBMERGENCE LEVELS

The selections of suitable variety are very crucial for addressing future challenges and sustainably increase rice production in the flood-prone rice-growing environment. To find out the degree of tolerance of different submergence tolerant varieties under different submergence durations we conducted the present research from July to December, 2018. The experiment comprised of two factors namely, factor A, Submergence durations were S0-control (no submergence situation), S1, S2,and S3 allowing submergence up to 10 days after seedling establishment (DAE), submergence up to 15 DAE, and submergence up to 20 DAE, respectively and factor B- Submergence tolerant varieties were Binadhan-11, Binadhan-12, BRRI dhan52, and BRRI dhan79. The experiment was laid out in a split-plot design where submergence durations were assigned to the main plots and varieties were assigned to the subplots with three replications. The highest grain yield (4.09 t ha-1) was obtained from no submergence situation with BRRI dhan52 followed by no submergence with variety Binadhan-11 (3.87 t ha-1), submergence up to 10 days after seedling establishment (3.61 t ha-1), and submergence up to 15 days after seedling establishment (3.35 t ha-1) with variety BRRI dhan52. Among four submergence tolerant varieties, BRRI dhan52 showed better performance.Thus, it may be concluded that submergence up to 10 or 15 days after seedling establishment with variety BRRI dhan52 might be cultivated in flood-affected areas where rice plants remain 10 to 15 days under floodwater.