Ten Sorghum genotypes were germinated in the laboratory to assess variation in root and coleoptile lengths and its effect on vigour and grain yield. Selections were made for long and short root as well as long and short coleoptile. The selected plants were transferred to the screen house and maintained for three weeks after which they were transplanted to the field in a Randomized Complete Block Design (RCBD) with three replications during the 2007 and 2008 cropping season. The seedlings were visually scored for vigour two weeks after transplanting. Mean root and coleoptiles lengths varied significantly (P < 0.01) among the genotypes used. Cultivar Samsorg14 was significantly longer in root and coleoptile lengths (11.59cm and 4.52cm) than the rest of the genotypes. Among selections for long root (LR) and long coleoptiles (LC), samsorg40 and samsorg41 consistently had the shortest root (6.79cm, 5.50cm) and coleoptile(2.17cm,1.47cm) lengths. The field performance of the sub-populations revealed highly significant differences among cultivars SSV20018 and SSV20021 for vigour. In both cases, the long root sub-populations had the highest vigour. Long coleoptile was highly significantly correlated with vigour(R=0.98, 0.78) and grain yield (0.77, 0.69) both phenotypically and genotypically.

Key words:Sorghum, selection, coleopitle length, vigour, grain yield