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1.
Proc Natl Acad Sci U S A ; 107(13): 5774-9, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20339079

RESUMO

This study examines the impact of two decades of neoliberal policy reform on food production and household livelihood security in three West African countries. The rice sectors in The Gambia, Côte d'Ivoire, and Mali are scrutinized as well as cotton and its relationship to sorghum production in Mali. Although market reforms were intended to improve food production, the net result was an increasing reliance on imported rice. The vulnerability of the urban populations in The Gambia and Côte d'Ivoire became especially clear during the 2007-2008 global food crisis when world prices for rice spiked. Urban Mali was spared the worst of this crisis because the country produces more of its own rice and the poorest consumers shifted from rice to sorghum, a grain whose production increased steeply as cotton production collapsed. The findings are based on household and market surveys as well as on an analysis of national level production data.


Assuntos
Política Nutricional/economia , Agricultura/economia , Comércio , Conservação dos Recursos Naturais , Côte d'Ivoire , Fibra de Algodão/economia , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Abastecimento de Alimentos/economia , Gâmbia , Gossypium/crescimento & desenvolvimento , Humanos , Fome , Internacionalidade , Mali , Marketing , Oryza/economia , Oryza/crescimento & desenvolvimento , Pobreza , Áreas de Pobreza , População Rural , Sorghum/crescimento & desenvolvimento , População Urbana
2.
Nat Plants ; 2: 16149, 2016 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-27694825

RESUMO

African rice (Oryza glaberrima) and African cultivation practices are said to have influenced emerging colonial plantation economies in the Americas1,2. However, the level of impact of African rice practices is difficult to establish because of limited written or botanical records2,3. Recent findings of O. glaberrima in rice fields of Suriname Maroons bear evidence of the high level of knowledge about rice among African slaves and their descendants, who consecrate it in ancestor rituals4,5. Here we establish the strong similarity, and hence likely origin, of the first extant New World landrace of O. glaberrima to landraces from the Upper Guinean forests in West Africa. We collected African rice from a Maroon market in Paramaribo, Suriname, propagated it, sequenced its genome6 and compared it with genomes of 109 accessions representing O. glaberrima diversity across West Africa. By analysing 1,649,769 single nucleotide polymorphisms (SNPs) in clustering analyses, the Suriname sample appears sister to an Ivory Coast landrace, and shows no evidence of introgression from Asian rice. Whereas the Dutch took most slaves from Ghana, Benin and Central Africa7, the diaries of slave ship captains record the purchase of food for provisions when sailing along the West African Coast8, offering one possible explanation for the patterns of genetic similarity. This study demonstrates the utility of genomics in understanding the largely unwritten histories of crop cultures of diaspora communities.


Assuntos
Produtos Agrícolas/genética , Genoma de Planta , Oryza/genética , Dispersão Vegetal , Polimorfismo de Nucleotídeo Único , África Ocidental , Etnicidade , Migração Humana , Humanos , Filogenia , Análise de Sequência de DNA , Suriname
3.
Nat Genet ; 46(9): 982-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25064006

RESUMO

The cultivation of rice in Africa dates back more than 3,000 years. Interestingly, African rice is not of the same origin as Asian rice (Oryza sativa L.) but rather is an entirely different species (i.e., Oryza glaberrima Steud.). Here we present a high-quality assembly and annotation of the O. glaberrima genome and detailed analyses of its evolutionary history of domestication and selection. Population genomics analyses of 20 O. glaberrima and 94 Oryza barthii accessions support the hypothesis that O. glaberrima was domesticated in a single region along the Niger river as opposed to noncentric domestication events across Africa. We detected evidence for artificial selection at a genome-wide scale, as well as with a set of O. glaberrima genes orthologous to O. sativa genes that are known to be associated with domestication, thus indicating convergent yet independent selection of a common set of genes during two geographically and culturally distinct domestication processes.


Assuntos
Genoma de Planta , Oryza/genética , África , Sequência de Aminoácidos , Sequência de Bases , Produtos Agrícolas/genética , DNA de Plantas/genética , Variação Genética , Genética Populacional/métodos , Dados de Sequência Molecular , Análise de Sequência de DNA/métodos
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