Geographical Patterns of Morphological Variation in Sorghum (Sorghum Bicolor (L.) Moench) Germplasm from Ethiopia and Eritrea: Qualitative Characters

Abstract

Four hundred and fifteen sorghum (Sorghum bicolor (L.) Moench) accessions consisting of 391 landraces collected from different geographical regions in Ethiopia and Eritrea, 8 varieties and 16 introduced elite breeding lines were used for this study. The materials were classified on the basis of regions of origin and adaptation zones. Phenotypic variation for ten qualitative (categorical) characters that displayed two or more classes were estimated using the Shannon‐Weaver diversity index (H'). High and comparable levels of phenotypic variation were found between the regions of origin and between the adaptation zones. However, significant levels of variation were found within the regions of origin and within the adaptation zones. Partitioning of the variation into within and between regions as well as into within and between adaptation zones further confirmed that a large portion of the total variation was found within regions of origin and within adaptation zones. Panicle compactness and shape contributed relatively more to regional differentiation. These characters were also found to be disproportionately distributed within the regions of origin with the compact panicles frequently distributed in relatively dry regions, while the loose panicle types were widely found in relatively wet and humid regions. The differential distribution of the different panicle types indicated the adaptive significance of panicle compactness and shape and at the same time reflected the distribution patterns of different races of sorghum in Ethiopia. Chi‐square analysis revealed that the occurrence of seed colour was non‐randomly associated with that of the other characters.

Phenotypic diversity for morphological and agronomic traits in traditional Ethiopian highland maize accessions

“…This result suggests that rainfall and growing season are the most important environmental factors differentiating traditional Ethiopian highland maize accessions. A similar result was reported by Ayana & Bekele (2000) in their study of morphological variation in sorghum collected from Ethiopia and Eritrea and noted that regional mean for plant height and days to maturity increases from north to south and from east to west, which followed the rainfall, temperature and seasonal patterns in Ethiopia (Tato, 1964).…”

Integration of Experiments across Diverse Environments Identifies the Genetic Determinants of Variation in Sorghum bicolor Seed Element Composition

“…Our data were not well modeled by a simple weight normalization (Supplemental Fig. S1), and we subsequently employed a rank transformation of the phenotypic data and linear model in the analysis (Ayana and Bekele, 2000;Baxter et al, 2014). …”

Seed weight increases with altitude in the Swiss Alps between related species but not among populations of individual species

“…A number of studies, dealing with single species and focussing on several aspects of plant life history, reported variation in seed weight with increasing altitude, but a consistent picture is not apparent. Most of these studies observed an increase (Mariko et al 1993;Oyama 1993;Holm 1994;Lord 1994;Piano et al 1996;Ayana and Bekele 2000;Boulli et al 2001;Blionis and Vokou 2002), some others a decrease (Totland and Birks 1996) or no alteration (Holm 1994;Kaya and Temerit 1994;Gera et al 2000) in seed weight with increasing altitude.…”