Investigation of population structure and genetic diversity of barley genotypes using AFLP molecular markers

Reduction in genetic diversity caused extreme vulnerability of crops to pests, diseases and environmental stresses will result in reduced yield. The genetic diversity of 77 barely genotypes were evaluated using seven AFLP combination primers. A total of 245 bands were generated which 227 were polymorph with average of 32.42 polymorphic band per marker. Average percentage of polymorphism and polymorphic information content were 92.37% and 0.43, respectively. General evaluation of the genetic diversity statistics including the number of effective alleles, Nei’s gene diversity and Shannon’s index showed that three primer combinations of E90-M160, E100 M160 and E100-M150 had higher values than the other combinations and had a more obvious role in distinguishing of the studied genotypes. Therefore, these primers are recommended to further studies on barely using AFLP makers. Cluster analysis using the neighbor joining method assigned genotypes to six groups. This type of grouping was nearly consistent with grouping of the genotypes in term of cold, warm or temperate climate, but not as comprehensive accordance. The analysis of population genetic structure using STRUCTURE software showed that population structure is separable into two main sub-populations with 21 and 35 genotypes, respectively, and 21 genotypes were identified as mixed genotypes. Genotypes of each sub-population had most similarity for allele frequencies and genetic structure and are different from the other groups. Results from this research can be used in future breeding programs such as association mapping.