Brassica rapa subspecies show morphological variability, containing vegetable types and oilseed types. The yellow sarson types(Brassica rapa ssp, tricolaris) have distinct morphology, yellow seeded and contain some lines with very unique character of tetralocular ovary. For genetic studies on tetralocular ovary related to high seed yields, we produced genetic segregation population with F2 and double haploid(DH) population. The yellow sarson LP8 (YS-033, CGN06835) with character of tetralocular ovary used as a maternal plant and crossed by LP21 of turnip rape type with bilocular ovary as paternal plant. We took on the microspore cultures on immature bud which is collected on sizing from 2mm to 3.2mm for DH population. The regenerations DH plants are analyzed by ploidy determination using flow cytrometer and selected on diploid plants. These regenerated DH and F2 plants are doing bud pollination and measuring the phenotype traits. Also, these populations will be used for identify of genetic locus relate to tetralocular ovary using genotyping by sequencing.