RESUMO

Maize was domesticated from teosinte, a wild grass, by approximately 6300 years ago in Mexico. After initial domestication, early farmers continued to select for advantageous morphological and biochemical traits in this important crop. However, the timing and sequence of character selection are, thus far, known only for morphological features discernible in corn cobs. We have analyzed three genes involved in the control of plant architecture, storage protein synthesis, and starch production from archaeological maize samples from Mexico and the southwestern United States. The results reveal that the alleles typical of contemporary maize were present in Mexican maize by 4400 years ago. However, as recently as 2000 years ago, allelic selection at one of the genes may not yet have been complete.

Assuntos

Alelos , Evolução Biológica , Produtos Agrícolas/genética , DNA de Plantas/genética , Seleção Genética , Zea mays/genética , Arqueologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Frequência do Gene , Genes de Plantas , Variação Genética , Espectrometria de Massas , México , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Sudoeste dos Estados Unidos , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia