Cereal Domestication and Evolution of Branching: Evidence for Soft Selection in the Tb1 Orthologue of Pearl Millet (Pennisetum glaucum [L.] R. Br.)
Figure 4
Conservation of PgTb1 function during plant development.
A. In-situ hybridization of the PgTb1 mRNA in serial transverse sections of a 10 day-old seedling of (a–c) the Souna landrace, (d–f) a 10 day-old wild seedling and (g) at the upper node of a mature wild plant (ms: main stem; as: axillary branch). Positions of the sections are given on the bottom-right diagram. B. Association of PgTb1 with domestication QTLs for tillering and branching in two domesticated x wild crosses. Souna and Tiotandé are landraces from Niger and Senegal, respectively. We mapped PgTb1 in the reference cross 81b x icmp451 to position the gene on the consensus pearl millet genetic map. The corresponding ZmTb1 locus and associated maize domestication QTLs are taken from ref. [24]. The percentage of variation explained by a QTL (R2) is reported beside its confidence interval (box). Abbreviations: till, tiller number; nb stems, total number of stems (tillers & branches); nb nodes, node number on the main stem; plht, plant height; lbil, average branch internode length on the main stem.