QTLs for oil yield components in an elite oil palm (Elaeis guineensis) cross

Abstract

Increased modern farming of superior types of the oil palm, Elaeis guineensis Jacq., which has naturally efficient oil biosynthesis, has made it the world's foremost edible oil crop. Breeding improvement is, however, circumscribed by time and costs associated with the tree's long reproductive cycle, large size and 10-15 years of field testing. Markerassisted breeding has considerable potential for improving this crop. Towards this, quantitative trait loci (QTL) linked to oil yield component traits were mapped in a high-yield population. In total, 164 QTLs associated with 21 oil yield component traits were discovered, with cumulative QTL effects increasing in tandem with the number of QTL markers and matching the QT? alleles for each trait. The QTLs confirmed all traits to be polygenic, with many genes of individual small effects on independent loci, but epistatic interactions are not ruled out. Furthermore, several QTLs maybe pleiotropic as suggested by QTL clustering of inter-related traits on almost all linkage groups. Certain regions of the chromosomes seem richer in the genes affecting a particular yield component trait and likely encompass pleiotropic, epistatic and heterotic effects. A large proportion of the identified additive effects from QTLs may actually arise from genic interactions between loci. Comparisons with previous mapping studies show that most of the QTLs were for similar traits and shared similar marker intervals on the same linkage groups. Practical applications for such QTLs in marker-assisted breeding will require seeking them out in different genetic backgrounds and environments.Electronic supplementary material The online version of this article

Genome-wide association study (GWAS) for morphological and yield-related traits in an oil palm hybrid (Elaeis oleifera x Elaeis guineensis) population

“…Further, Billotte et al [15] used a multi-parent linkage map elaborated with 251 SSRs and reported QTLs associated with bunch traits. Similar approaches have enabled the identification of 164 QTLs associated with 21 oil yield components using SSR, AFLP, and RFLP markers [16].…”

In silico characterization and expression profiling of the diacylglycerol acyltransferase gene family (DGAT1, DGAT2, DGAT3 and WS/DGAT) from oil palm, Elaeis guineensis

“…Genetically speaking, oil accumulation in plant tissues is a complex quantitative trait that involves numerous genes. Efforts to increase oil yields in commercially valuable crops, such as E. guineensis and oilseeds like soybean, require the identification of the specific genes that regulate this highly desirable agronomic trait so that breeders can focus on variation involving those key genes [52] in a similar manner to efforts to manipulate the acyl quality of the oil [53]. It is becoming increasingly apparent that DGAT activity is pivotal to increasing…”

Review: Omics and Strategic Yield Improvement in Oil Crops

“…GWAS, QTL and association mapping studies have been increasingly reported for oil palm breeding, particularly for oil content [115][116][117][118][119][120]. Bai et al [116] showed that by combining QTLs with beneficial genotypes, the resulting average oil content in fruit bunches was higher.…”

“…This platform was particularly useful for developing early trait prediction methods to shorten the oil palm breeding cycle and was used to identify QTL loci for important oil content traits [115]. Informative QTLs linked to oil yield component traits were also mapped in a high-yield population [118]. The authors highlighted the significance of cumulative effects of quantitative trait allele analysis for each trait contributing to oil yield components.…”