scholarly journals New adaptive peaks for crops – an example from improvement of drought-resilience of sorghum in Ethiopia

2021 ◽  
Author(s):  
Hongxu Dong ◽  
Techale Birhan ◽  
Nezif Abajebel ◽  
Misganu Wakjira ◽  
Cornelia Lemke ◽  
...  
Keyword(s):  
Balancing Selection ◽  
Field Tests ◽  
Climate Extremes ◽  
Marginal Populations ◽  
Nested Association Mapping ◽  
Drought Resilience ◽  
Center Of Diversity ◽  
History Of ◽  
Sub Saharan ◽  
Elite Cultivar

As the center of diversity for sorghum [Sorghum bicolor (L.) Moench], elite cultivars selected in Ethiopia are of central importance to sub-Saharan food security. Despite being presumably well adapted to their center of diversity, elite Ethiopian sorghums nonetheless experience constraints to productivity, for example associated with shifting rainfall patterns associated with climate change. A sorghum backcross nested association mapping (BC-NAM) population developed by crossing thirteen diverse lines pre-identified to have various drought resilience mechanisms, with an Ethiopian elite cultivar, Teshale, was tested under three rain-fed environments in Ethiopia. 27, 15, and 15 QTLs with predominantly small additive effects were identified for days to flowering, days to maturity, and plant height, respectively. Many associations detected in this study corresponded closely to known or candidate genes or previously mapped QTLs, supporting their validity. Field tests show drought resilience to be improved by incorporation of adaptations from the diverse donor lines. The expectation that genotypes such as Teshale from near the center of diversity tend to have a history of strong balancing selection, with novel variations more likely to persist in small marginal populations, was strongly supported in that for these three traits, nearly equal numbers of alleles from the donor lines conferred increases and decreases in phenotype relative to the Teshale allele. Such rich variation provides a foundation for selection to traverse a 'valley' of reduced yield and arrive at a new 'adaptive peak', exemplifying the nature of efforts that may be necessary to adapt many crops to new climate extremes.

Christianity in the Twentieth Century

2019 ◽  
Author(s):  
Brian Stanley
Keyword(s):  
Latin America ◽  
Racial Identity ◽  
Sub Saharan Africa ◽  
Central Importance ◽  
Regional Survey ◽  
History Of Christianity ◽  
The World ◽  
History Of ◽  
Sub Saharan ◽  
Different Parts

This book charts the transformation of one of the world's great religions during an age marked by world wars, genocide, nationalism, decolonization, and powerful ideological currents, many of them hostile to Christianity. The book traces how Christianity evolved from a religion defined by the culture and politics of Europe to the expanding polycentric and multicultural faith it is today—one whose growing popular support is strongest in sub-Saharan Africa, Latin America, China, and other parts of Asia. The book sheds critical light on themes of central importance for understanding the global contours of modern Christianity, illustrating each one with contrasting case studies, usually taken from different parts of the world. Unlike other books on world Christianity, this one is not a regional survey or chronological narrative, nor does it focus on theology or ecclesiastical institutions. The book provides a history of Christianity as a popular faith experienced and lived by its adherents, telling a compelling and multifaceted story of Christendom's fortunes in Europe, North America, and across the rest of the globe. It demonstrates how Christianity has had less to fear from the onslaughts of secularism than from the readiness of Christians themselves to accommodate their faith to ideologies that privilege racial identity or radical individualism.

scholarly journals Genomic Dissection of Peduncle Morphology in Barley through Nested Association Mapping

Plants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 10
Author(s):  
Sebastian Zahn ◽  
Thomas Schmutzer ◽  
Klaus Pillen ◽  
Andreas Maurer
Keyword(s):  
Quantitative Trait Loci ◽  
Association Mapping ◽  
Cross Section ◽  
Quantitative Trait ◽  
Spring Barley ◽  
Raw Material ◽  
Total Thickness ◽  
Nested Association Mapping ◽  
Elite Cultivar ◽  
Major Qtl

Straw biomass and stability are crucial for stable yields. Moreover, straw harbors the potential to serve as a valuable raw material for bio-economic processes. The peduncle is the top part of the last shoot internode and carries the spike. This study investigates the genetic control of barley peduncle morphology. Therefore, 1411 BC1S3 lines of the nested association mapping (NAM) population “Halle Exotic Barley 25” (HEB-25), generated by crossing the spring barley elite cultivar Barke with an assortment of 25 exotic barley accessions, were used. Applying 50k Illumina Infinium iSelect SNP genotyping yielded new insights and a better understanding of the quantitative trait loci (QTL) involved in controlling the peduncle diameter traits, we found the total thickness of peduncle tissues and the area of the peduncle cross-section. We identified three major QTL regions on chromosomes 2H and 3H mainly impacting the traits. Remarkably, the exotic allele at the QTL on chromosome 3H improved all three traits investigated in this work. Introgressing this QTL in elite cultivars might facilitate to adjust peduncle morphology for improved plant stability or enlarged straw biomass production independent of flowering time and without detrimental effects on grain yield.

scholarly journals Nucleotide Variation at theCHALCONE ISOMERASELocus inArabidopsis thaliana

Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 863-872 ◽  
Author(s):  
Helmi Kuittinen ◽  
Montserrat Aguadé
Keyword(s):  
Nucleotide Diversity ◽  
Direct Relationship ◽  
Selective Sweep ◽  
Balancing Selection ◽  
Neutral Theory ◽  
Low Frequency ◽  
The Other ◽  
Nucleotide Variation ◽  
Rapid Population Growth ◽  
History Of

AbstractAn ~1.9-kb region encompassing the CHI gene, which encodes chalcone isomerase, was sequenced in 24 worldwide ecotypes of Arabidopsis thaliana (L.) Heynh. and in 1 ecotype of A. lyrata ssp. petraea. There was no evidence for dimorphism at the CHI region. A minimum of three recombination events was inferred in the history of the sampled ecotypes of the highly selfing A. thaliana. The estimated nucleotide diversity (θTOTAL = 0.004, θSIL = 0.005) was on the lower part of the range of the corresponding estimates for other gene regions. The skewness of the frequency spectrum toward an excess of low-frequency polymorphisms, together with the bell-shaped distribution of pairwise nucleotide differences at CHI, suggests that A. thaliana has recently experienced a rapid population growth. Although this pattern could also be explained by a recent selective sweep at the studied region, results from the other studied loci and from an AFLP survey seem to support the expansion hypothesis. Comparison of silent polymorphism and divergence at the CHI region and at the Adh1 and ChiA revealed in some cases a significant deviation of the direct relationship predicted by the neutral theory, which would be compatible with balancing selection acting at the latter regions.

scholarly journals Recombination and Selection at Brassica Self-Incompatibility Loci

Genetics ◽  
1999 ◽  
Vol 152 (1) ◽  
pp. 413-425 ◽  
Author(s):  
Philip Awadalla ◽  
Deborah Charlesworth
Keyword(s):  
Linkage Disequilibrium ◽  
Balancing Selection ◽  
Brassica Species ◽  
Selective Constraint ◽  
Intragenic Recombination ◽  
Self Incompatibility ◽  
History Of ◽  
Unknown Gene ◽  
Slg Gene ◽  
High Diversity

Abstract In Brassica species, self-incompatibility is controlled genetically by haplotypes involving two known genes, SLG and SRK, and possibly an as yet unknown gene controlling pollen incompatibility types. Alleles at the incompatibility loci are maintained by frequency-dependent selection, and diversity at SLG and SRK appears to be very ancient, with high diversity at silent and replacement sites, particularly in certain “hypervariable portions of the genes. It is important to test whether recombination occurs in these genes before inferences about function of different parts of the genes can be made from patterns of diversity within their sequences. In addition, it has been suggested that, to maintain the relationship between alleles within a given S-haplotype, recombination is suppressed in the S-locus region. The high diversity makes many population genetic measures of recombination inapplicable. We have analyzed linkage disequilibrium within the SLG gene of two Brassica species, using published coding sequences. The results suggest that intragenic recombination has occurred in the evolutionary history of these alleles. This is supported by patterns of synonymous nucleotide diversity within both the SLG and SRK genes, and between domains of the SRK gene. Finally, clusters of linkage disequilibrium within the SLG gene suggest that hypervariable regions are under balancing selection, and are not merely regions of relaxed selective constraint.

Forced Labour in the “Gorgulho Years”: Understanding Reform and Repression in Rural São Tomé e Príncipe, 1945–1953

Itinerario ◽  
2014 ◽  
Vol 38 (1) ◽  
pp. 103-124 ◽  
Author(s):  
Alexander Keese
Keyword(s):  
Economic Change ◽  
Social Conditions ◽  
Sub Saharan Africa ◽  
History Of ◽  
Colonial Policies ◽  
Sub Saharan ◽  
Incomplete Images ◽  
Forced Labour ◽  
Sao Tome E Principe

The crossroads of nationalist historiographies in sub-Saharan Africa and of the history of developmentalist attempts that characterise the European late colonial states, have left us with very incomplete images of important trajectories. In the seemingly more “liberal” large colonial empires—notably the French and British—sails were set by 1945 towards a policy of investment and economic change. Some of the scholarly debates question whether this investment was genuine or just a last resort to avoid (rapid) decolonisation; others put the emphasis on inadequate routines of development implemented in these territories, many of which have apparently been continued since decolonisation.In this context, we encounter a clear lack of understanding about how decisions made by individual actors on the administrative level interacted with the larger panorama of social conditions in colonial territories, and of the consequences that these interactions had for the paths towards decolonisation. For a smaller empire such as the Belgian colony of Congo-Léopoldville, these processes are still more obscure; and for the colonies ruled by authoritarian metropoles, as in the cases of territories under Spanish and Portuguese rule, stagnation and absence of change are often taken for granted. In other words, these territories, which were under the rule of metropoles regarded as rather weak in economic terms, are treated as unrepresentative of the broader, European movement towards change in colonial policies. However, the conditions of change towards economic and social modernisation in this latter group of empires, even when inhibited by lack of funding and weak professionalisation of the administration, are frequently very telling for the broader range of challenges that the late colonial states faced.

Women in Gabon

2021 ◽  
Author(s):  
Claire H. Griffiths
Keyword(s):  
Central Africa ◽  
Early Period ◽  
Sub Saharan Africa ◽  
African Women ◽  
Female Population ◽  
History Of ◽  
Sub Saharan ◽  
Tropical Woods ◽  
New Research ◽  
Export Revenue

Gabon, a small oil-rich country straddling the equator on the west coast of Africa, is the wealthiest of France’s former colonies. An early period of colonization in the 19th century resulted in disease, famine, and economic failure. The creation of French Equatorial Africa in 1910 marked the beginning of the sustained lucrative exploitation of Gabon’s natural resources. Gabon began off-shore oil production while still a colony of France. Uranium was also discovered in the last decade of the French Equatorial African empire. Coupled with rich reserves in tropical woods, Gabon has achieved, since independence in 1960, a higher level of export revenue per capita of population than any other country in sub-Saharan Africa in the postcolonial era. However, significant inequality has characterized access to wealth through paid employment throughout the recorded history of monetized labor. While fortunes have been amassed by a minute proportion of the female population of Gabon associated with the ruling regime, and a professional female middle-class has emerged, inequalities of opportunity and reward continue to mark women’s experience of life in this little-known country of West Central Africa. The key challenge facing scholars researching the history of women in Gabon remains the relative lack of historical resources. While significant strides have been made over the past decade, research on women’s history in Francophone Africa published in English or French remains embryonic. French research on African women began to make a mark in the last decade of colonization, notably with the work of Denise Paulme, but then remained a neglected area for decades. The publication in 1994 of Les Africaines by French historian Catherine Coquery-Vidrovitch was hailed at the time as a pioneering work in French historiography. But even this new research contained no analysis of and only a passing reference to women in Gabon.

Experimental Study and Numerical Analysis of Sihui Metro Depot and the Superstructure

2012 ◽  
Vol 226-228 ◽  
pp. 176-180
Author(s):  
Jing Zhang ◽  
Bin Zhang ◽  
Ying Hua Liu ◽  
Long Qi Wang ◽  
Yu Bin Wu
Keyword(s):  
Time History ◽  
Field Tests ◽  
Element Model ◽  
Test Analysis ◽  
3 Dimensional ◽  
Dimensional Finite Element ◽  
Calculation Results ◽  
History Of ◽  
The Given ◽  
The Waves

Field tests were carried out on Sihui metro depot of Beijing metro line 1 and its superstructure. The acceleration time history of sleepers and floors of the building was obtained, and the waves-propagation laws of building were studied through the tests. Test analysis shows that the structure vibrations show zigzag tendencies ascends with the height of the building. Based on current situation of Sihui metro depot, a metro-soil-building 3-dimensional finite element model is established on ANSYS. By using actual acceleration of sleepers as inputs, the dynamic responds rule of the superstructure is obtained. Compared calculation results with the experimental results, the given numerical model can predict the vibrations of the building induced by moving trains quite well. This method can provide guidance and technical support for future development of superstructure.

The History of Romantic Love in Sub-Saharan Africa: between Interest and Emotion

2011 ◽  
Author(s):  
Megan Vaughan
Keyword(s):  
Romantic Love ◽  
Sub Saharan Africa ◽  
Historical Study ◽  
History Of ◽  
Political Project ◽  
Sub Saharan ◽  
Theoretical Issues

This chapter looks at the history of romantic love in Sub-Saharan Africa. This text comes from a lecture given at the British Academy's 2009 Raleigh Lecture on History. This text attempts to explore some of the methodological and theoretical issues involved in an historical study of love in Africa. It argues that romantic love in Africa is not simply an extension of an imperialist cultural and political project and that emotional regimes cannot be divorced from economic circumstances. It explains that though the configurations of interest and emotion take specific forms in African societies, there is nothing peculiarly African about the evident need of individuals to balance realism and idealism in their emotional lives.

Film Comedy in Africa

2020 ◽  
pp. 211-242
Author(s):  
William V. Costanzo
Keyword(s):  
Oral Traditions ◽  
Political Humor ◽  
Ousmane Sembene ◽  
Black Africa ◽  
Pan Africanism ◽  
The World ◽  
Djibril Diop Mambety ◽  
History Of ◽  
The Rich ◽  
Sub Saharan

The rich oral traditions of storytelling in Black Africa have evolved into cinematic forms, adapting social satire and political humor to the realities of modern life. After a brief history of the region and its early encounters with the medium of motion pictures, this chapter introduces concepts like négritude, the griot storyteller, pan-Africanism, and Afropolitanism to explain how African beliefs and sub-Saharan cinema differ from others in the world and how African filmmakers like Ousmane Sembène and Djibril Diop Mambéty, Jean-Pierre Bekolo and Adama Drabo, Henri Duparc and Benoît Lamy, Flores Gomes and Fanta Régina Nacro have fashioned a cinema that reflects the way Africans see themselves and their place in the world.

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