Inheritance of a broad leaf phenotype in the tobacco cultivar hicks

Abstract

This study has shown that a broad leaf phenotype, known as Hamilton Hicks, was homozygous for one allele at one locus (hh). It is believed that the inheritance of this phenotype has not been reported previously. However, plants of this type have been present in the Queensland strain of the Hicks cultivar for several years, with a frequency in the commercial crop of about 0.02%. The non-Hamilton phenotype was homozygous for another allele at the locus ( +^h +^h), and the heterozygote was of intermediate phenotype. The heterozygote demonstrated changing expressivity during ontogeny. In the juvenile stages, the heterozygote appeared very similar to the Hamilton phenotype, but, when mature, it was similar to the non-Hamilton phenotype. Descriptions of all phenotypes are given. Some suggestions comparing this locus with others affecting leaf shape are presented.