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The oil palm (E. guineensis Jacq.) genome, estimated by flow cytometric analysis (Rival et al., 1997), is 3.4 × 10⁹ bp and Madon et al. (1998) reported the chromosome number of both E. guineensis and E. oleifera to be 32.

E. guineensis × E. oleifera interspecific hybrids produce a specific oil with higher unsaturated fatty acids, and they display a slower vertical growth (20 cm/year rather than 60 cm for E. guineensis) and resistance to diseases (vascular wilt for Africa, and especially bud rot for Latin America). The current objective of breeders is to introgress major desirable traits of E. oleifera into E. guineensis through backcross programmes. For the last 30 years or so, the interspecific hybrid has been unavoidable when replanting palms in specific areas thanks to its strong resistance to bud rot in Latin America. Work is in progress to improve the interspecific hybrid not only by exploiting new E. oleifera accessions but also by cloning the best individuals thus taking advantage of within-progeny variability (Cochard et al., 2005).

The oil palm is a versatile crop with multiple uses for its oil. The commodity chain is driven by a wide diversity of stakeholders (growers, crop researchers, oleo-chemists and technologists, engineers, environmentalists, anthropologists, marketers, etc.). This diverse population is able to propose many suggestions for desirable selection traits to improve the palm and its oil. It is thus important for key stakeholders to reconcile, rationalize and prioritize the selection traits for improvement as it is cumbersome and inefficient for breeders to include all the desirable traits in their breeding programme at any one time, and there may also be obvious or hidden negative trade-offs between pairs of traits (Chin et al., 2017). The recurrent cycles of selection have successfully removed a lot of ‘unwanted’ alleles from the breeding populations, thereby providing a mere 1% genetic gain each year for the oil palm (Cochard et al., 2005). However, this might have affected the populations’ ability to withstand environmental threats (Rival, 2017) and genetic gains in the future. Realizing the important role of oil palm germplasm in harmonizing these effects, several research organizations had accumulated a large number of E. guineensis and E. oleifera accessions from their centres of origin. Such materials exhibit greater genetic diversity and can offer genes for many economically important traits for future oil palm improvement (Ithnin et al., 2017).