Fig. 1
The OxG mapping population and BC2 validation crosses used in this study. The 108 OxG interpecific hybrids (left) were created by crossing a maternal Colombian E. oleifera (UP1026) with a paternal palm T128 (tenera), from the Nigerian germplasm. The same T128 palm was also used in creating the BC2 validation crosses (right). The La Mé E. guineensis (L2T, maternal parent) was crossed with a Colombian E. oleifera (79/4.4–12/6.61, paternal parent) and the resulting GxO F1 hybrid (983/2.4–43/15.90) was then backcrossed with the T128 palm to produce the BC1. Pollen from a selected BC1 palm (335/5.2–5/23.96) was used to cross-pollinate two E. guineensis palms. The first E. guineensis (1084/TP51/22.32) was derived from a cross between the T128 and a Serdang pisifera and the second palm (320/TT113/22.32) was derived from a self-pollination of the T128 palm. The two BC2 families namely, 2.6–1 and 2.6–5 consisted of 74 and 80 palms, respectively