Genetic analysis of the domestication syndrome in pearl millet (Pennisetumglaucum L, Poaceae): inheritance of the major characters

The inheritance of domestication traits distinguishing pearl millet (Pennis etum glaucum) from its wild relatives (P. mollissimum) was assessed in F-2 progenies derived from a cross between a typical landrace of pearl millet a nd a wild ecotype. Despite a high level of recombination between the two ge nomes, the existence of preferential associations between some characters w as demonstrated, leading, in particular, to cultivated-like phenotypes. Tra its determining spikelet structure showed simple Mendelian inheritance. Mor eover, the genes encoding these traits mapped in a linkage group where quan titative trait loci for spike size and tillering habit were found. This lin kage group could correspond to one of the two chromosome segments that have already been shown to be involved in the variation for spikelet structure in progenies from several cultivated x wild crosses. A synthetic map of the se two regions is given. The evolutionary significance of this genomic orga nization in relation to the domestication process is discussed, as well as its potential use for pearl millet genetic resources enhancement.