Stratification of SADC regional sorghum testing sites based on grain yield of varieties uri icon

abstract

  • We applied sequential retrospective (SeqRet) pattern analysis to stratify sorghum variety testing sites according to their similarity for yielddiscrimination among genotypes using historical grain yield data from 147 multi-environment trials (METs). The trials were conducted at 38sites in 10 countries of the Southern African Development Community (SADC) region during 1987/1988?1992/1993 and 1999/2000. Theanalysis for the 6 years 1987/1988?1992/1993, covering 34 sites, clustered these sites into 6 major groups with a model fit of R2 = 0.75.Withadditional data from the year 1999/2000, the SeqRet pattern analysis delivered a very similar clustering of the 34 sites, with the additional foursites in 1999/2000 properly classified with appropriate site groups (R2 = 0.74). The results suggest that future sorghum variety testing could berestricted to a few representative sites selected from within each of the six identified site-groups

publication date

  • 2006
  • 2006