Storage Proteins Profile in Diploid and Tetraploid Seeds of Oryza sativa L.

Four diploid rice lines vis-à-vis their respective tetraploids were analyzed by comparing the variations in the seed protein characteristics. The autotetraploids had higher protein content as compared to their parental lines with the maximum relative increase of 63% in case of tetraploid of the parental line ‘Kuma’. The alkali soluble glutelins were the dominating protein fraction in all the diploids and their tetraploid lines. The proportion of albumin and globulin fractions in the seeds of tetraploids of ‘Pusur’, ‘Kuma’ and ‘Tougou’ decreased and that in the tetraploid of ‘Nourin’ registered an increase. With major polypeptides resolving in the range of MW 110 to 13 kDa, the polypeptide patterns of the total seed protein extracts of diploids and their tetraploids under non-reducing and reducing conditions did not show any qualitative differences. Most of the polypeptides of ‘Nourin’ and ‘Pusur’ tetraploids appeared darker as compared to their respective diploid parents. Densitometric scanning of the SDS-gels exhibited more than 10% increase in the relative concentration of polypeptides of MW 78, 65, 60, 40.5, 38, 36, 29, 25, 21 and 13 kDa in ‘Nourin 4x’, 78, 36, 21 and 13 kDa in ‘Kuma 4x’, 78, 65, 40.5, 38, 36, 25 and 21 kDa in ‘ Pusur 4x’ and 38 and 21in ‘Tougou 4x’. Maximum densitometric increase was noticed for glutelin polypeptides of MW 25 kDa in ‘Nourin 4x’, 21 kDa in ‘Kuma 4x’, 36 kDa in ‘Pusur 4x’ and 38 kDa in ‘Tougou 4x’ as compared to their respective diploid parents.