Observation On Yield Attributes And Quality Analysis Of Potential Mutant Lines With Drought Tolerance
Plant responses to water stress vary according to species, severity of the stress and the plants growth stage when the water limitation occurs. This study was focused to develop drought tolerance rice mutant lines with the same grain quality of original rice variety. In this paper, the local rice variety, Manawthukha was used to develop drought tolerant mutants through gamma radiation. The treatment of water stress was exposed to the plants from reproductive stage (90 days after sowing) until harvesting time. Ten potential lines with three hundred panicles from M2 generation were selected for next generation. The desiccation of apical spikelets in stressed panicles was obviously found in summer cultivation in M4 generation as well as M2. Hence, the control plants were not fertilized under water deficit condition while other mutant plants fertilized at that time. In M3 and M5 generation, rainy season cultivation, it was observed that plant height of control plants were significantly lower than that of mutant lines. Promising mutant lines, namely MK-D-2, MK-D-3, MK-F-1 and MK-F-2 with significantly improved drought tolerance and yield potential were grown as M5 generation. From this generation, rice grain qualities of drought tolerant potential lines were determined in the laboratory. Finding shows that there were no large differences in amylose content of rice samples from potential lines and control. Among the potential mutant lines, MK-D-3 showed higher husking yield and total mean milling recovery than the control and other mutant lines. . It is concluded that another studies related drought stress should be further investigated as potential indirect means of improving drought tolerant mutants.
Keywords- Amylose content, Drought tolerance, Grain quality, Potential mutant lines