A Critical Evaluation Revealed the 'Proto-indica' Model Rests on a Weaker Foundation and Has a Minimal Bearing on Rice Domestication

Abstract

We have evaluated the 'proto-indica' model that is the proponent of multiple domestication of rice but a single origin of the key genes in 'japonica'. Attainment of non-shattering, a marker; appeared least integral to the initial phases of domestication. The other archeological determinants were less discernible in specimens. Existence of the key domestication genes in the wild rice and absence of introgression signature in 'indica' further weakened the hypothesis. Moreover, 'japonica' introduction from China happened in a backdrop of a culture exploiting domesticated rice. Summarizing, we propose that 'proto-indica' model has a little bearing on rice domestication.