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The potential for exploiting heterosis for sorghum hybrid production in Ethiopia with improved local adaptation and farmers preferences has been investigated and populations suitable for initial hybrid development have been identified. Hybrids in sorghum have demonstrated increased productivity and stability of performance in the developed world. In Ethiopia, the uptake of hybrid sorghum has been limited to date, primarily due to poor adaptation and absence of farmer's preferred traits in existing hybrids. This study aimed to identify complementary parental pools to develop locally adapted hybrids, through an analysis of whole genome variability of 184 locally adapted genotypes and introduced hybrid parents (R and B). Genetic variability was assessed using genetic distance, model-based STRUCTURE analysis and pair-wise comparison of groups. We observed a high degree of genetic similarity between the Ethiopian improved inbred genotypes and a subset of landraces adapted to lowland agro-ecology with the introduced R lines. This coupled with the genetic differentiation from existing B lines, indicated that these locally adapted genotype groups are expected to have similar patterns of heterotic expression as observed between introduced R and B line pools. Additionally, the hybrids derived from these locally adapted genotypes will have the benefit of containing farmers preferred traits. The groups most divergent from introduced B lines were the Ethiopian landraces adapted to highland and intermediate agro-ecologies and a subset of lowland-adapted genotypes, indicating the potential for increased heterotic response of their hybrids. However, these groups were also differentiated from the R lines, and hence are different from the existing complementary heterotic pools. This suggests that although these groups could provide highly divergent parental pools, further research is required to investigate the extent of heterosis and their hybrid performance.

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The increase superiority in characteristics such as size, growth rate, fertility, yield and general fitness of hybrids produced by crossing genetically diverse inbred parents is well established in many plant and animal species. This phenomenon has been exploited to produce commercial cultivars in a range of crop species including sorghum.In sorghum F1 hybrid seed is produced by crossing genetically distinct restorer (R lines) and cytoplasmic male sterile seed parent (A lines). In the developed world commercial cultivars are almost exclusively F1 hybrids and are increasingly being used in the developing countries. In spite of the yield advantage in some circumstances, however, hybrids developed using introduced parental lines have not been adopted by Ethiopian farmers primarily because of the extra cost of purchasing seed has not been outweighed by the benefits of introduced hybrids in particular the lack of farmer preferred traits such as tall stature and larger grain size. The development of hybrids using locally adapted genotypes could have the potential to overcome the shortcomings of introduced hybrids. However, the complex cytoplasmic male sterility system and prevalence of restorer genes complicate the development of new Additionally, the hybrids derived from these locally adapted genotypes will have the benefit of containing farmers preferred traits. The groups most divergent from the introduced A/B lines were the Ethiopian landraces adapted to highland and intermediate agro-ecologies and a subset of lowland adapted genotypes. These genotype groups were also grouped distinctly from the introduced R lines, and hence provide highly divergent parental lines for hybrid development in Ethiopia.The performance and magnitude of heterosis of 139 F1 hybrids, derived from introduced seed parents crossed with selected locally adapted genotypes and introduced R lines, were evaluated in three contrasting environments. The lowland adapted hybrids displayed a mean better parent heterosis (BPH)iii of 19% and a 29% increase in grain yield, on average, in comparison to the hybrids derived from the introduced R lines. In addition, these hybrids were also found to be superior in plant height and grain weight. The mean BPH for grain yield for the highland adapted hybrids was 16% in the highland and 52 % in the intermediate, in addition to increased grain weight. The magnitude of heterosis between the three hybrid groups reflected the genetic distance between the genotype groups with the A/B lines.These results highlight the potential of locally adapted genotypes for the exploitation of heterosis in Ethiopia.In order to understand the genetic basis of increased hybrid performance, the relationship between yield component traits was assessed and the genetic variance for each subset of hybrid group was partitioned into parental lines and their interaction effects. In the lowland environment, increase in grain number and grain weight contributed to increased yield of the lowland adapted hybrids in comparison to the intro...

Sorghum is a drought tolerant C 4 tropical crop with wide diversity grown for food, feed and beverages. There is a growing demand for food and malt type sorghum varieties due to the low supply of mat barley, and climate resilient and gluten free nature of the crop. This study was initiated to estimate the associations among traits and the relative importance of traits in influencing grain yield and malting quality of sorghum genotypes. The experiment was conducted at Fachagama in Mhoni ARC, Northern Ethiopia in 2016/2017 using αlattice design in two replications using supplementary irrigation. Data were collected on agronomic traits, and a selection of 300 g pure seeds were malted (18 hr steeping, 72 hr in 28°C germinated and 24 hr in 50°C dried) for malt quality analysis. Positive and significant correlations with grain yield of TKW (0.766, 0.715), KL (0.671, 0.644), KW (0.524, 0.491) HLW (0.532, 0.504, FHWE (0.257, 0.241) and DP (0.275, 0.271) at both phenotypic and genotypic level was found respectively. TKW exerted high positive genotypic (0.334) and phenotypic (0.287) direct effect and even higher indirect effect on grain yield, which indicated that attention should be given to TKW primarily for direct and indirect selection for yield improvement. Thousand kernel weight and fine grind hot water extract showed a significant positive correlation with diastatic power at genotypic level and increment in these traits results in advancement of diastatic power.

Sorghum [Sorghum bicolor (L.) Moench] is an important grain crop in many parts of the world, especially in dry regions. It is an important crop for food and feed and its role in energy production is also currently growing. The demand for food and feed has shown an increasing trend due to the increasing human population and economic growth. Sorghum hybrids have demonstrated superior performances in the developed world as compared to their inbred parents. However, the technologies 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 data were then analyzed using statistical packages (DarWin, PowerMarker, and GenAlex). 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.

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.