The co‐dominance theory: Genetic interpretations of analyses of mesocarp oils fromelaeis guineensis,elaeis oleifera and their hybrids

Abstract

Determination of the fatty acid and triglyceride compositions of the F~ (Elaeis guineensis • E. oleifera), F a and the backcross hybrid mesocarp oils demonstrated that most fatty acid and triglyceride compositions of oils from hybrid palms are intermediate between those of their respective parentals. These data, as well as the acyl group (samrated/palmimte and unsaturated/oleate) distribution of trigtycerides of the F 2 mesocarp oils provide genetic proof for codominance in the F a generation which shows a characteristic segregation into the co-domlnance ratio of 1:2:1 (i.e., 1 E. guineensis: 2 F 1 hybrid: 1 E. oleifera). Similar analyses into the backcross hybrid mesocarp oils on the whole confirmed co-dominance when the backcross ratio of 1:1 was obtained. These remits are used to develop the Co-Dominance Theory of Elaeis palm hybridization which makes successful predictions for mesocarp oils from the different hybrid palms. ABSTRACTThe fatty acid and sterol compositions of different parts of Malagasy zebu (Bos indicus) were evaluated. Investigation by gas liquid chromatography using Carbowax 20 M revealed 35 fatty acids, mainly palmitic (24-27%), stearic (13-24%), and oleic (25-37%) acids. Oddnumbered, iso and anteiso fatty acids were also detected. Small differences in composition were observed between the hump and the kidney fats of B. indicus. Comparison between industrial tallow of B. indicus and B. taurus revealed slight differences in the stearic/ oleic acid ratio (0.83 and 0.46, respectively). An OV 17 column was used to separate 9 sterols, mainly cholesterol (89-98%). fl-Sitosterol was also found at lower concentrations in all the samples.

Quantitative trait loci (QTLs) analysis of palm oil fatty acid composition in an interspecific pseudo-backcross from Elaeis oleifera (H.B.K.) Cortés and oil palm (Elaeis guineensis Jacq.)

“…An interspecific cross E. oleifera × E. guineensis shows mean values for fatty acid proportions which are intermediate between the mean values of its E. oleifera and E. guineensis parents (Hardon 1969;Macfarlane et al 1975;Meunier and Boutin 1975;Opute and Obasola 1979;Tan et al 1985). This is in accordance with the codominance theory for genes involved in palm oil biosynthesis and their alleles inherited from each Elaeis parent (Hardon 1969;Ong et al 1981). Surprisingly, the proportion of oleic acid of the interspecific hybrid parent SA65T was quite similar to the one of its E. oleifera parent of the Brazilian Coari origin (Table 1).…”

“…The species E. oleifera has a very low yield in palm oil compared to commercial oil palm varieties (Tan et al 1985), but it has several desirable agronomic characteristics: Elaeis oleifera presents a slow growth of the stem (Hardon 1969), shows resistance to the bud rot disease in South America (Meunier 1991), and a more edible palm oil in its fatty acid composition and concentrations of metabolites (carotenes, tocoferols, and tocotrienols) also important for the phytopharmaceutical industry (Choo et al 1997). Genetic advantageous features from both Elaeis species can be combined by interspecific hybridization for creating more performing oil palm varieties (Ong et al 1981). The palm oil of E. guineensis contains approximately 50 % of saturated fatty acids, with 44 % of palmitic acid (C16:0), 5 % of stearic acid (C18:0), and trace amounts of myristic acid (C14:0).…”

Chemical Characteristics and Nutritional Properties of Hybrid Palm Oils

“…As a rule, the FA composition of oils from F1 O×G interspecific hybrids is intermediate between those of their parents [3,4,38], while FAs in the F1 × F1 (i.e. the F2 generation) exhibit the composition of F1 [38].…”

Oil palm natural diversity and the potential for yield improvement

“…Amongst the E. oleifera accessions, the unsaturated FA content ranges from 47 to 69% for C18:1, 2 to 19% for C18:2, and 0.1 to 1.2% for C18:3. Interspecies E. oleifera × E. guineensis hybrids planted in Latin America have a mid-parent phenotype with iodine index varying from 58 to 71% (Ong et al, 1981). Nineteen QTL’s controlling FA composition were identified in the interspecies pseudo-backcross populations (Montoya et al, 2014).…”