Evaluation of anaerobic germination and submergence tolerance in rice (Oryza sativa L.) suitable for direct seeded condition

The leading target domain in lowland areas is improving the tolerance for anaerobic germination and submergence, especially in direct-seeded rice (DSR). The present study identified elite genotypes with tolerance for anaerobic germination and submergence among 25 diverse rice genotypes. This study adopted four experimental conditions (three in the lab and one in the field): anaerobic germination in water, anaerobic germination with soil and water, submergence condition and direct seeded rice in the field. The recorded traits showed significant variation under all four stresses. Chitiraikar performed well in anaerobic germination and DSR experiments. CO55 registered the highest trait value of seedling height and early vegetative vigour in the anaerobic experiment with water. Aanaikomban, Karunguruvai, Karuppukavuni and Chitiraikar outperformed other genotypes in most of the above experimental conditions. Thus, choosing lines based on germination percentage, early seedling vigour, elongation index and seedling survival rate can increase tolerance for anaerobic germination and submergence conditions in the lab and DSR method. Among all the experiments conducted, anaerobic germination with soil and water and the DSR method was found to be reliable for screening a large population.