Genetic Relationships among Sorghum [Sorghum bicolor (L.) Moench] Lines and Correlation between Genetic Distance and Hybrid Performance

Abstract

In certain cases the improved and released sorghum varieties are not being used by Ethiopian farmers because of lack of farmers preferred traits in the hybrids developed so far.  This study was conducted to identify the genetic potential of selected sorghum inbred lines involving landraces, introduced and improved lines and its effect on combining ability and hybrid performance to use for hybrid development. Genetic diversity of 37 inbred lines used for the test hybrids was assessed using 7339 SNP markers. The genotypes were grouped into four clusters, with the Ethiopian landraces depicting clear distinction from the introduced and breeding lines. The result implies that efforts might be needed to bring the best genes from the landraces for the hybrid breeding. Genetic distance between inbred lines estimates based on SNP markers ranged from 0.02 to 0.358 with an average of 0.247, indicating the very narrow genetic distance for this study. The regression analysis indicates that grain yield showed an increment as the genetic distance among parental lines increased. Generally, the genetic distance between lines and regression analysis played vital role in determining which lines showed yield increment.  Thus, sorghum lines with desirable trait of interests were properly identified for future sorghum breeding program