Root system architecture traits diversity and association with grain yield for drought adapted sorghum genotypes

Abstract Background and aims The roots system architecture of sorghum is a major morphological trait which strongly influences the capacity to access soil moisture and forage nutrients under drought condition. This study was conducted aiming to the extent of genetic diversity among sorghum genotypes adapted the dryland; to identify promising genotypes for key root and shoot traits for breeding purposes; and to determine the contribution of root related traits of sorghum on moisture stress area. Methods The experiment was conducted using 214 genotypes in greenhouse of Horticulture and Plant science Department, Jimma University using randomized complete block design. Results Cluster analysis indicated that the genotypes grouped into eight cluster. Number of genotypes per cluster varied from 100 (46.72%) in Cluster II and 2 (0.93%) genotypes both in Cluster III and VI .The maximum genetic distance (D 2 =151.36) obtained between cluster III and VIII and minimum genetic distance (D 2 =9.38) was found between cluster V and VII also the intra-cluster distance was highest in the cluster II (D 2 =43.93) and the lowest cluster found VI (D 2 =0.93). Root angle and root length exhibited strong negative(r=- 0.24 ) and positive correlation (r= 0.32 ) with grain yield. Genotypes Acc#220249(58); Acc#220254(#59); Acc#234102(#102); Acc#235811(#118) Acc#20710(27) the most divergent on the principal axis of biplot and used direct sorghum improvement. Conclusion The information generated from this study could help to identified promising genotypes with suitable root traits for potential breeding under specific environmental conditions.