Phylogeography of Asian wild rice, <i>Oryza rufipogon</i> , reveals multiple independent domestications of cultivated rice, <i>Oryza sativa</i>

TLDR

Cultivated rice is the world’s most important staple, yet its domestication history from wild ancestor Oryza rufipogon remains unclear. The study investigates rice domestication by examining DNA variation in three gene regions using a phylogeographic approach. The authors analyze DNA sequence variation in three gene regions across populations in a phylogeographic framework. The analysis shows India and Indochina as the ancestral diversity center of O.

Abstract

Cultivated rice, Oryza sativa L., represents the world's most important staple food crop, feeding more than half of the human population. Despite this essential role in world agriculture, the history of cultivated rice's domestication from its wild ancestor, Oryza rufipogon, remains unclear. In this study, DNA sequence variation in three gene regions is examined in a phylogeographic approach to investigate the domestication of cultivated rice. Results indicate that India and Indochina may represent the ancestral center of diversity for O. rufipogon. Additionally, the data suggest that cultivated rice was domesticated at least twice from different O. rufipogon populations and that the products of these two independent domestication events are the two major rice varieties, Oryza sativa indica and Oryza sativa japonica. Based on this geographical analysis, O. sativa indica was domesticated within a region south of the Himalaya mountain range, likely eastern India, Myanmar, and Thailand, whereas O. sativa japonica was domesticated from wild rice in southern China.