Millets across Eurasia: chronology and context of early records of the genera Panicum and Setaria from archaeological sites in the Old World

We have collated and reviewed published records of the genera Panicum and Setaria (Poaceae), including the domesticated millets Panicum miliaceum L. (broomcorn millet) and Setaria italica (L.) P. Beauv. (foxtail millet) in pre-5000 cal b.c. sites across the Old World. Details of these sites, which span China, central-eastern Europe including the Caucasus, Iran, Syria and Egypt, are presented with associated calibrated radiocarbon dates. Forty-one sites have records of Panicum (P. miliaceum, P. cf. miliaceum, Panicum sp., Panicum type, P. capillare (?) and P. turgidum) and 33 of Setaria (S. italica, S. viridis, S. viridis/verticillata, Setaria sp., Setaria type). We identify problems of taphonomy, identification criteria and reporting, and inference of domesticated/wild and crop/weed status of finds. Both broomcorn and foxtail millet occur in northern China prior to 5000 cal b.c.; P. miliaceum occurs contemporaneously in Europe, but its significance is unclear. Further work is needed to resolve the above issues before the status of these taxa in this period can be fully evaluated

Setaria

International audienceFoxtail millet, Setaria italica (L.) Beauv., is the only Setaria grown as crop. It is a small grain cereal of the Paniceae tribe. It has long been important for human consumption in China and India where it was domesticated more than 8,000 years ago. It is also grown in small quantities throughout Eurasia for some traditional uses and for feeding birds, and in Europe and America for hay and silage. The chapter describes the taxonomy, the biology, and the role in crop breeding of the few wild relatives pertaining to its gene pool complex, all known as noxious weeds. They include its putative wild ancestor, S. viridis (green foxtail), which forms the primary gene pool at a diploid level of genome A and comprises the progeny of the spontaneous hybrids between the two taxa, S. viridis ssp. pycnocoma. The secondary gene pool includes the diploid of genome B, S. adhaerans (bristly grass), and the allotetraploid AB species S. verticillata (bristly foxtail) and S. faberi (giant foxtail). This small number of wild related species was in fact seldom used for foxtail millet genetic improvement, except only in a few cases of research for male sterility and herbicide resistance. The reason for such little impetus could be due to the structure of the wild–weed–crop primary gene pool, which provided enough genetic diversity through “off-types” and the selection of many diverse landraces. In addition, their success as weeds as the consequence of intentional and unintentional weed management for over 10,000 years perhaps reduced the field of selectable beneficial traits. In contrast, wild Setaria were invaluable resources to gain better knowledge of the genome organization of the crop. Besides phylogeny, cytogenetics, genetic attributes and mating system, phenotypic variation, distribution and population genetics of the wild species as well as interspecific breeding methods are documente