Oil palm (Elaeis guineensis Jacq.) is the most traded crop among the economically important palm species. Here, we report an extended version genome of E. guineensis that is 1.2 Gb in length, an improvement of the physical genome coverage to 79% from the previous 43%. The improvement was made by assigning an additional 1968 originally unplaced scaffolds that were available publicly into the physical genome. By integrating three ultra-dense linkage maps and using them to place genomic scaffolds, the 16 pseudomolecules were extended. As we show, the improved genome has enhanced the mapping resolution for genome-wide association studies (GWAS) and permitted further identification of candidate genes/protein-coding regions (CDSs) and any non-coding RNA that may be associated with them for further studies. We then employed the new physical map in a comparative genomics study against two other agriculturally and economically important palm species-date palm (Phoenix dactylifera L.) and coconut palm (Cocos nucifera L.)-confirming the high level of conserved synteny among these palm species. We also used the improved oil palm genome assembly version as a palm genome reference to extend the date palm physical map. The improved genome of oil palm will enable molecular breeding approaches to expedite crop improvement, especially in the largest subfamily of Arecoideae, which consists of 107 species belonging to Arecaceae.
Maternal depression has been linked to the development of adolescents’ emotional and behavioural problems. The main objective of this study was to determine the association between maternal depressive disorders and externalizing and internalizing problems among their adolescent children. This was a cross-sectional, comparison study of 35 mothers with depression and their adolescents, matched with 35 healthy mothers and their adolescents as controls. The mothers completed Quick Inventory Depressive Symptomatology (QIDS) for assessment of current depression. The emotional and behavioural problems in the adolescents were assessed independently by the mothers and their adolescents off-springs using Child Behavioral Checklist (CBCL) and Youth Self-Report (YSR), respectively. SPSS version 12.0 was used for statistical analysis. The findings showed that adolescents who have mothers with depressive disorders had significantly higher scores of externalizing (mean difference = 4.686 + 10.887, p = 0.016) and total emotional and behavioural problems (mean difference = 10.171 + 23.007, p = 0.013) than controls. The cases also scored higher than the controls in the following CBCL syndrome scales: aggressive behaviour (mean difference = 3.200 + 6.773, p = 0.008), social problem (mean difference = 1.286 + 2.865, p = 0.012), and attention problem (mean difference = 1.543 + 4.435, p = 0.047). Mothers with depressive disorders reported that their adolescents have greater emotional and behavioural problems than the controls. The findings suggested a need for preventive strategies to curb problematic behaviour focusing on this vulnerable group.