Isozyme variation in Ethiopian tetraploid wheat (Triticum turgidum) landrace agrotypes of different seed color groups

Ethiopian landraces of tetraploid wheat can be grouped according to their seed colors in three major groups: brown, purple and white seeded. Seeds with different colours are used for different purposes, and the three seed colour groups are treated separately in breeding programs. The genetic variation between and within these groups was studied by isozyme analyses at six highly polymorphic loci in sixty landrace agrotypes. The mean number of alleles per locus was 1.95. The mean allele frequencies showed significant variation both within and between the seed colour groups. The brown and white seeded types had very high genetic identity and the genetic identity values between the brown and purple and the purple and white groups were only slightly smaller. The average coefficient of gene differentiation between the seed colour types was very low. Only about 5% of the total genetic variation was due to differences between the seed colour groups. This indicates that agrotypes of different seed colours can not be treated as genetically separate and distinct groups.