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There has been limited research conducted on the coconut genome (Aljohi et al., 2016). Both Tall and Dwarf varieties of coconut are diploid, with 32 chromosomes (Neto et al., 2016). Genome size reports vary. Gunn et al. (2015) reported that the coconut genome size averaged 5.97 pg or 5.76 Gb for the diploid, with significant variation between varieties. Neto et al. (2016) reported the mean coconut genome size to be 5.57 pg (5.59 pg for Tall and 5.55 pg for Dwarf), with only a small difference between the varieties examined. Gunn (2004) was responsible for the first phylogenetic analysis of coconut DNA, with chloroplast studies following (Asmussen et al., 2000; Hahn, 2002a,b; Asmussen et al., 2006).

The chloroplast and mitochondrial genomes have been sequenced by Huang et al. (2013) and Aljohi et al. (2016), respectively. The Dwarf coconut chloroplast genome is smaller than Tall palms. It has an increased number of RNA editing sites and a unique pseudogenization of the rps19-like gene. However, it still has the same overall organization, gene content and repeat structure of other palms (Huang et al., 2013). Results also indicate that coconut is more closely related to oil palm (Elaeis guineensis Jacq.) than to date palm (Phoenix dactilifera L.). The mitochondrial genome of the Oman Local Tall is 678,653 bp, encoding 72 proteins, 9 pseudogenes, 23 tRNAs and 3 ribosomal RNAs, and has a 45.5% guanine-cytosine content (Aljohi et al., 2016). The mitochondrial genome has been compared with other plant species and genes identified, e.g. sdh gene, that are present in coconut but absent in seven other monocot species so far studied (Aljohi et al., 2016).

The coconut nuclear genome is almost twice the size of oil palm and four times larger than the date palm (Gunn et al., 2015) and a draft coconut sequence has been reported (Alsaihati et al., 2014). Complete genome sequencing will provide important insights into decoding traits involved in pest and disease resistance, fruit morphology, and those of agroecological importance, i.e. cold, drought and salt tolerance. The differentiation of plant tissue type would be of particular value in exposing the presence of genes involved in the regulation of somatic embryogenesis. Information gained will also be important for decision making regarding germplasm conservation activities (Loiola et al., 2016).