The inheritance of primin secretion in Primula obconica

The inheritance of primin secretion in Primula obconica was determined by s tudying the F-1, F-2 and BC1 progenies of crosses between primin-secreting cultivars and primin-free ones. All plants in a ten-cross combination of F-1 secreted primin; thus, the pri min-secreting phenotype was dominant over the primin-free phenotype. In four of ten cross combinations, the factor segregated in F-2 and BC1 as Mendelian ratios of 3:1 and 1:1, respectively, indicating that primin secre tion is controlled by a single gene. However, in another six cross combinat ions, the segregation ratios of F-2 mere significantly different from 3:1, whereas those of BC1 were 1:1. The results suggested that the distorted seg regations observed in certain F-2 might have been caused by certation or ga metic selection. Given the above findings, the inheritance of primin secretion, which was ch aracterized by distorted segregations in certain F-2 was found to be contro lled by a major gene.