Identification and Sequencing of Gene Related to Length of Rice Grain

Objective The gene that regulates the length of a rice grain, which directly relates to crop yield, was identified and sequenced for breed improvement.

Method  Through map-based cloning, 499 recombinant inbred lines derived from the interspecific cross between Jiafuzhan (indica) and Nipponokin (japonica) were employed to identify the quantitative trait loci associated with the phenotypic trait.

Result A major plasmid length of GS3 was detected in the recombinant inbred line population located approximately within the physical distance of 1,851 kb. Since only the 48^th base of the second exon was mutated from C to A between the genes of Jiafuzhan and Nipponbare, protein translation was no longer necessary. Further analysis on Jiazao No. 1 and Jiafuxiangzhan bred using the GS3 showed no significant difference than the wild type Jiafuzhan in grain length, width, or length-width ratio.

Conclusion  The information on GS3 obtained in this study was of value for future studies to genetically improve rice production.