Assessing population genetic structure of sorghum landraces from North-western Morocco using allozyme and microsatellite markers

The level of genetic diversity and the population genetic structure of sorg hum landraces from North-western Morocco have been investigated based on di rect field-sampling using both allozyme and microsatellite markers. As expe cted, microsatellite markers showed a much higher degree of polymorphism th an allozymes, but relative measures of genetic structure such as Wright's i nbreeding coefficient F-IS and Nei's coefficient of genetic differentiation GST were similar for the two Sets of markers. Substantial inbreeding was f ound to occur within fields, which confirms that sorghum is predominantly s elfing under cultivation, Most of the genetic diversity in Moroccan landrac es occurs within fields (more than 85%), as opposed to among fields or amon g regions, a result which contrasts to those of studies based on accessions from germplasm collections. It is suggested that individual fields of sorg hum constitute valuable units of conservation in the context of in situ con servation practices.