The arches and spandrels of maize domestication, adaptation, and improvement

Crop plants were domesticated by prehistoric farmers through artificial selection to provide a means of feeding the human population. This article discusses the developmental genetics of crop domestication and improvement, including the historical framework and recent approaches in maize and other grasses. In many cases, selecting for a plant form that correlates with productivity involves controlling meristem activity. In the domestication of modern maize from its progenitor Zea mays ssp. parviglumis, QTL (quantitative trait loci) mapping, genetics and population genomics approaches have identified several genes that contain signatures of selection. Only a few genes involved in the derivation of the highly productive maize ear have been identified, including teosinte glume architecture1 and ramosa1. Future prospects hinge on forward and reverse genetics, as well as on other approaches from the developing discipline of evo-devo (evolutionary developmental biology).

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Contrasted patterns of selection since maize domestication on duplicated genes encoding a starch pathway enzyme

Theoretical and Applied Genetics ◽

10.1007/s00122-010-1480-9 ◽

2010 ◽

Vol 122 (4) ◽

pp. 705-722 ◽

Cited By ~ 11

Author(s):

J. Corbi ◽

M. Debieu ◽

A. Rousselet ◽

P. Montalent ◽

M. Le Guilloux ◽

...

Keyword(s):

Duplicated Genes ◽

Genes Encoding ◽

Maize Domestication

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Evolutionary and food supply implications of ongoing maize domestication by Mexican campesinos

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.1049 ◽

2018 ◽

Vol 285 (1885) ◽

pp. 20181049 ◽

Cited By ~ 20

Author(s):

Mauricio R. Bellon ◽

Alicia Mastretta-Yanes ◽

Alejandro Ponce-Mendoza ◽

Daniel Ortiz-Santamaría ◽

Oswaldo Oliveros-Galindo ◽

...

Keyword(s):

Breeding Population ◽

Smallholder Agriculture ◽

Maize Production ◽

Adaptive Mutations ◽

Family Farmers ◽

Level Data ◽

The World ◽

Mother Plants ◽

Maize Domestication ◽

Municipal Level

Maize evolution under domestication is a process that continues today. Case studies suggest that Mexican smallholder family farmers, known as campesinos , contribute importantly to this, but their significance has not been explicitly quantified and analysed as a whole. Here, we examine the evolutionary and food security implications of the scale and scope under which campesinos produce maize. We gathered official municipal-level data on maize production under rainfed conditions and identified campesino agriculture as occurring in municipalities with average yields of less than or equal to 3 t ha −1 . Environmental conditions vary widely in those municipalities and are associated with a great diversity of maize races, representing 85.3% of native maize samples collected in the country. We estimate that in those municipalities, around 1.38 × 10 11 genetically different individual plants are subjected to evolution under domestication each season. This implies that 5.24 × 10 8 mother plants contribute to the next generation with their standing genetic diversity and rare alleles. Such a large breeding population size also increases the total number of adaptive mutations that may appear and be selected for. We also estimate that campesino agriculture could potentially feed around 54.7 million people in Mexico. These analyses provide insights about the contributions of smallholder agriculture around the world.

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