Abstract
The inheritance of primin secretion in Primula obconica was determined by studying the F1, F2 and BC1 progenies of crosses between primin-secreting cultivars and primin-free ones. All plants in a ten-cross combination of F1 secreted primin ; thus, the primin-secreting phenotype was dominant over the primin-free phenotype. In four of ten cross combinations, the factor segregated in F2 and BC1 as Mendelian ratios of 3 : 1 and 1 : 1, respectively, indicating that primin secretion is controlled by a single gene. However, in another six cross combinations, the segregation ratios of F2 were significantly different from 3 : 1, whereas those of BC1 were 1 : 1. The results suggested that the distorted segregations observed in certain F2 might have been caused by certation or gametic selection. Given the above findings, the inheritance of primin secretion, which was characterized by distorted segregations in certain F2 was found to be controlled by a major gene.
