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Oil palm (Elaeis guineensis Jacq.) is an outbreeding perennial tree crop with long breeding cycles, typically 12 years. Molecular marker technologies can greatly improve the breeding efficiency of oil palm. This study reports the first use of the DArTseq platform to genotype two closely related self-pollinated oil palm populations, namely AA0768 and AA0769 with 48 and 58 progeny respectively. Genetic maps were constructed using the DArT and SNP markers generated in combination with anchor SSR markers. Both maps consisted of 16 major independent linkage groups (2n = 2× = 32) with 1399 and 1466 mapped markers for the AA0768 and AA0769 populations, respectively, including the morphological trait "shell-thickness" (Sh). The map lengths were 1873.7 and 1720.6 cM with an average marker density of 1.34 and 1.17 cM, respectively. The integrated map was 1803.1 cM long with 2066 mapped markers and average marker density of 0.87 cM. A total of 82% of the DArTseq marker sequence tags identified a single site in the published genome sequence, suggesting preferential targeting of gene-rich regions by DArTseq markers. Map integration of higher density focused around the Sh region identified closely linked markers to the Sh, with D.15322 marker 0.24 cM away from the morphological trait and 5071 bp from the transcriptional start of the published SHELL gene. Identification of the Sh marker demonstrates the robustness of using the DArTseq platform to generate high density genetic maps of oil palm with good genome coverage. Both genetic maps and integrated maps will be useful for quantitative trait loci analysis of important yield traits as well as potentially assisting the anchoring of genetic maps to genomic sequences.

Breeding values obtained from best linear unbiased prediction (BLUP) were used to rank nine pisifera (P) male parents belonging to two different but related genetic groups, utilising highly unbalanced data from three D (Dura) x P progeny-test trials of oil palm . The traits studied were fresh fruit bunch yield (FFB), total number of bunches (BNo), average bunch weight (BW), oil to bunch percentage (OB) and average annual height increment (HINC) . Four P's from the AVROS genetic group had higher breeding values for FFB, BNo and OB while five P's from the Dumpy-AVROS group were superior in breeding values for BW and HINC . Selection of parents based on the average of the rankings in breeding value for BNo, OB and HINC for each parent tended to favour AVROS P's . However, selection of parents based on the aggregate genetic worth function involving relative economic values, tended to favour Dumpy-AVROS P's . The latter method is preferred to the average ranking method because of its emphasis on relative economic values and the selection index approach .It is suggested that the BLUP technique may prove to be a very useful tool in oil palm breeding .

In a 7x7 diallel-cross experiment utilizing parents with varying resistance to mosaic virus disease and of different horticultural types significant heterosis over the better parent was found in number of days between sowing and flowering and over the mean of the two parents in other characters. The combining ability analysis revealed that genetic control of most character variation was due to additive effects.

Abstract. Biotechnological applications in oil palm breeding comprises tissue culture propagation (TC), genetic modification (GM), marker-assisted breeding (MAB), and marker-assisted selection (MAS). Commercial success of oil palm TC has been hampered by the fruit mantling somaclonal variation risk, inefficient cloning process and inefficient ortet selection. With the imminent availability of the mantling marker and subsequently markers for cloning and palm selection efficiencies, the scenario would change. Despite early enthusiasm, GM oil palm remains at the R&D level and only for the high oleic trait, because of technical complexity and public sensitivity. Marker-assisted breeding, population genetic diversity, homozygosity determination and linkage disequilibrium have made most impact in oil palm breeding. With the revelation of the oil palm whole genome sequence, the feasibility of MAS for many major quantitative gene locus (QTL) traits e.g. shell, fruit colour, mantling, long stalk, lipase are being expedited. Meanwhile for minor QTL controlling yield and other traits, oil palm breeders are testing the feasibilities of genomewide breeding/genetic value estimation for MAS of hybrid parents, families and individuals. Undoubtedly, biotechnological tools will continue improving but their success depends on the field breeder who provides the essential genetic trials to develop the biotechnological tools and to validate their utility.

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