Biology subjects

Tadesse, Z.

Publications and source records attributed to Tadesse, Z..

3 recordsLinked to original sources

bioRxiv2021

Predicting the distributions of Pouteria adolfi-friederici and Prunus africana iconic tree species under current and future climate change scenarios in Ethiopia

The distributions of the potential adaptive ranges of iconic plant species are not yet fully known especially in regions such as Ethiopia where high climatic variability and vegetation types are found. This study was undertaken to predict the distributions of the potential suitable habitats of Pouteria adolfi-friederici and Prunus africana tree species under the current and two future climate scenarios (i.e., RCP 4.5 and RCP 8.5 in 2050 and 2070) using MaxEnt software (version: 3.4.4.). Eleven less correlated environmental variables (r<0.7) were identified and used to make the prediction models. Elevational shifts of the highly suitable habitats, effects of elevation, solar radiation and topographic position in relation to the current and future climatic scenarios on the habitats were statistically analyzed using independent t-test and linear model. Under all climate scenarios, we found a decrease in the proportion of areas of highly suitable habitats for both study species. High potentials of suitable habitats for Pouteria adolfi-friederici are predicted to be confined to southwest, west central and south parts of Ethiopia in fragmented moist afromontane forest patches, while it is in the southwest and west central parts of Ethiopia for Prunus africana. On basis of vegetation types of the country, potential suitable habitats for Pouteria adolfi-friederici are predicted to occur in moist evergreen forest, dry evergreen forest and grassland complex and Combretum-Terminalia woodland vegetation types. Whereas, moist evergreen forest, dry evergreen forest and grassland complex and riverine vegetation types are predicted to comprise potential suitable habitats for Prunus africana, showing considerable spatial dynamics. Overall, our results suggest that the strategies deem to design biodiversity conservation should take into account the dynamics of the suitable niches of different species under different future climate scenarios.

ecology↗

bioRxiv2020

Genomics of Ocular Chlamydia trachomatis after 5 years of SAFE interventions for trachoma in Amhara, Ethiopia

BackgroundTo eliminate trachoma as a public health problem, the WHO recommends the SAFE strategy. As part of the SAFE strategy in the Amhara Region, Ethiopia, the Trachoma Control Program distributed over 124 million doses of antibiotic between 2007 and 2015. Despite these interventions, trachoma remained hyperendemic in many districts and a considerable level of Chlamydia trachomatis (Ct) infection was evident. MethodsWe utilised residual material from Abbott m2000 Ct diagnostic tests to sequence 99 ocular Ct samples from Amhara and investigated the role of Ct genomic variation in the continued transmission of Ct following 5 years of SAFE. FindingsSequences were typical of ocular Ct, at the whole-genome level and in tissue tropism-associated genes. There was no evidence of macrolide-resistance in this Ct population. Polymorphism in a region around ompA gene was associated with village-level TF prevalence. Additionally, greater ompA diversity at the district-level was associated with increased Ct infection prevalence. InterpretationWe found no evidence for Ct genomic variation contributing to continued transmission of Ct after treatment, adding to previous evidence that azithromycin does not drive acquisition of macrolide resistance alleles in Ct. Increased Ct infection in villages and in districts with more ompA variants requires longitudinal investigation to understand what impact this may have on treatment success and host immunity. FundingEuropean Commission; Neglected Tropical Disease Support Center; International Trachoma Initiative

genomics↗

bioRxiv2020

Allelic diversity study of functional genes in East Africa bread wheat highlights opportunities for genetic improvement.

Wheat (Triticum aestivum L.) is a major staple crop in East Africa (EA) providing 9% and 10% of daily calories and protein intake, respectively. However, EA countries depend on import to meet 55% of their domestic wheat supplies due to increasing demands and low domestic yields. To determine the beneficial gene pool currently exploited for wheat improvement in EA, we examined the allelic diversity of 42 genes of breeding importance in a collection of 239 wheat cultivars and breeding lines from Kenya and Ethiopia using KASP markers. The assayed genes have been shown to control variations in plant height, thousand kernel weight (TKW), grain protein content, pre-harvest sprouting (PHS), disease resistance and flowering time. We observed the beneficial alleles of some major genes including Rht-D1, Gpc-B1, Yr5, Yr15, Sr26, and Fhb1 to be missing or present at low frequencies in this population. Furthermore, we validated the effects of the major Rht-1 alleles and TaCKX-6A in controlling variation in plant height and thousand kernel weight, respectively, under EA conditions. Our results uncover hitherto unexploited allelic diversity that can be used to improve the genetic potential of EA wheat germplasm. This will inform strategies to rapidly mobilize these beneficial alleles for wheat improvement in EA.

genetics↗