9 research outputs found
Yield and bunch quality component comparison between two-way crosses and multi-way crosses of DxP oil palm progenies
Breeding for hybrid DxP oil palm in many commercial seed producers has recently switched from simple two-way crosses to complicated multi-way crosses with the hope of increasing hybrid vigour and thus higher yield potential. The objective of this study was to evaluate the yield potential of the multi-way (MW) crosses as compared to conventional two way (TW) crosses in United Plantations Berhad. A trial was set up in 2004 where 20 crosses of both multi-way and two-way combinations were field planted and evaluated for six years after maturity. Palms were assessed for yield traits and bunch components through bunch analysis. Fresh fruit bunch weight for both types of crosses was significantly different with MW crosses yielding 37.11 tonnes per ha per year as opposed to TW crosses with 36.40. MW crosses had 1.46 tonnes oil per ha per year advantage over TW. High coefficient of variation (CV%) was seen for selected traits such as bunch number (BNO), average bunch weight (ABW), kernel, shell and mesocarp to bunch (KB, SB and MB), oil to dry and oil to wet mesocarp (ODM and OWM), as well as mean fruit weight (MFW). ANOVA showed that replicate (REP), year (Y) and progeny (ID) were significantly different (p≤0.01) for BNO and fresh fruit bunch (FFB) in both crosses but not significant for REP in ABW of TW. REP was not significant for all the traits except ODM whereas ID was significant for all the traits in both TW and MW. Phenotypic and genotypic coefficients of variance (PCV and GCV) were low (<10%) for all the traits in both types of crosses with MW crosses showing higher PCV and GCV in most cases. Heritability for ABW, FFB, KB, oil to bunch (OB), SB and MFW were higher in MW crosses but lower for BNO, fruit to bunch (FB), MB, ODM and OWM compared to TW crosses
Candidate genes linked to QTL regions associated with fatty acid composition in oil palm
© 2020, Institute of Molecular Biology, Slovak Academy of Sciences. The present study searched for candidate genes in five linkage groups (LGs) - T2, T3, OT4, OT6 and T9 hosting the QTLs associated with iodine value (IV) and fatty acid composition (FAC) in an oil palm interspecific hybrid population. Each of the five LGs was successfully anchored to its corresponding chromosomal segment where, a wider repertoire of candidate genes was identified. This study further revealed a total of 19 candidate genes and four transcription factors involved in biosynthesis of fatty acids, lipids (including triacylglycerol) and acetyl-CoA, glycosylation and degradation of fatty acids. Their possible involvement in regulating the levels of saturation are discussed. In addition, 22 candidate genes located outside the QTL intervals were also identified across the interspecific hybrid genome. A total of 92 SSR markers were developed to tag the presence of these candidate genes and 50 were successfully mapped onto their respective positions on the genome. The data obtained here complements the previous studies, and collectively, these QTL-linked candidate gene markers could help breeders in more precisely selecting palms with the desired FAC
Expression of fatty acid and triacylglycerol synthesis genes in interspecific hybrids of oil palm
© 2020, The Author(s). Evaluation of transcriptome data in combination with QTL information has been applied in many crops to study the expression of genes responsible for specific phenotypes. In oil palm, the mesocarp oil extracted from E. oleifera × E. guineensis interspecific hybrids is known to have lower palmitic acid (C16:0) content compared to pure African palms. The present study demonstrates the effectiveness of transcriptome data in revealing the expression profiles of genes in the fatty acid (FA) and triacylglycerol (TAG) biosynthesis processes in interspecific hybrids. The transcriptome assembly yielded 43,920 putative genes of which a large proportion were homologous to known genes in the public databases. Most of the genes encoding key enzymes involved in the FA and TAG synthesis pathways were identified. Of these, 27, including two candidate genes located within the QTL associated with C16:0 content, showed differential expression between developmental stages, populations and/or palms with contrasting C16:0 content. Further evaluation using quantitative real-time PCR revealed that differentially expressed patterns are generally consistent with those observed in the transcriptome data. Our results also suggest that different isoforms are likely to be responsible for some of the variation observed in FA composition of interspecific hybrids
Development and evaluation of tenera oil palm progenies derived from single, double and three-way crosses
Commercial oil palm plantings in Malaysia are primarily composed of single crosses. These crosses have limitations in their genetic potential, thus hindering efforts for further yield improvements. The primary objective of this study was to evaluate the yield potential, bunch characteristics and vegetative traits of oil palm progenies created from single (SC), three-way (TW) and double crosses (DC) and to assess their suitability for higher density planting. Thirty Dura x Pisifera (D × P) crosses were created using different parental lines to produce three samples of varying cross types, SC (10), TW (10) and DC (10) and planted in a randomized complete block design (RCBD) with three replicates (16 palms per replication). Except for a single round of vegetative measurements, palm yields and bunch characteristics were evaluated for a period of five years. All data were analysed using a Statistical Analysis Software (SAS ver. 9.4). The yield performance summarized by cross type showed significantly higher fresh fruit bunch (FFB) production in DC (210.42 kg per palm per year) compared to SC (187.00) and TW (196.94). The highest broad sense heritability estimates calculated decreases in the order: SC > TW > DC. There were no significant differences between the three cross types for all the bunch components analysed except for mean weight per fruit (MWF); approximately 17% higher in both TW and DC compared to SC. Estimated fresh fruit bunch yields per hectare (FFBHa) was 12.5 and 6.8% higher in DC compared to SC and TW, respectively. Oil yield per hectare (OHa) and oil yield per palm (OYP) for DC was 17.6 and 10.7% higher than SC and TW, respectively. There were no significant differences between cross types for any of the vegetative traits quantified in this study. For the same parameters, within crop types, DC showed the most significant differences between progenies indicating the highest segregation of vegetative traits. Progenies DC2, SC8, DC9, TW7, TW2, SC1, SC3 and DC1 with short fronds showed the greatest potential for higher density planting. The DC2 with the shortest fronds planted at a density of 201 palms per hectare is estimated to yield 10.66 t ha-1 oil annually. Strong significant positive correlations existed between OYP/OHa and average bunch weight (BWT), mesocarp to bunch ratio (MB), oil to bunch ratio (OB) and FFBHa. There was no significant correlations observed between any of the vegetative traits with yield or bunch components. Path coefficient analysis carried out showed contrasting results between SC and both TW and DC. In all three cross types however, fruit to bunch ratio (FB) and MB possessed the greatest influence over OHa both as a direct effect and indirect effect through other traits. Creation of multiway crosses did improve yield potentials with DC showing a clear advantage over the others. The creation of multiway crosses is therefore a vital step in breeding leading to higher segregation enabling the selection of an array of traits useful in the endeavours to improve commercial yields nationwide
An integrated linkage map of interspecific backcross 2 (BC2) populations reveals QTLs associated with fatty acid composition and vegetative parameters influencing compactness in oil palm
This study sought to identify quantitative trait loci (QTLs) associated with fatty acid composition (FAC) and vegetative traits for compactness in oil palm. It integrated two interspecific backcross two (BC2) mapping populations to improve the genetic resolution and evaluate the consistency of the QTLs identified
An integrated linkage map of interspecific backcross 2 (BC2) populations reveals QTLs associated with fatty acid composition and vegetative parameters influencing compactness in oil palm
This study sought to identify quantitative trait loci (QTLs) associated with fatty acid composition (FAC) and vegetative traits for compactness in oil palm. It integrated two interspecific backcross two (BC2) mapping populations to improve the genetic resolution and evaluate the consistency of the QTLs identified
An integrated linkage map of interspecific backcross 2 (BC2) populations reveals QTLs associated with fatty acid composition and vegetative parameters influencing compactness in oil palm
Background Molecular breeding has opened new avenues for crop improvement with the potential for faster progress. As oil palm is the major producer of vegetable oil in the world, its improvement, such as developing compact planting materials and altering its oils’ fatty acid composition for wider application, is important. Results This study sought to identify the QTLs associated with fatty acid composition and vegetative traits for compactness in the crop. It integrated two interspecific backcross two (BC2) mapping populations to improve the genetic resolution and evaluate the consistency of the QTLs identified. A total 1963 markers (1814 SNPs and 149 SSRs) spanning a total map length of 1793 cM were integrated into a consensus map. For the first time, some QTLs associated with vegetative parameters and carotene content were identified in interspecific hybrids, apart from those associated with fatty acid composition. The analysis identified 8, 3 and 8 genomic loci significantly associated with fatty acids, carotene content and compactness, respectively. Conclusions Major genomic region influencing the traits for compactness and fatty acid composition was identified in the same chromosomal region in the two populations using two methods for QTL detection. Several significant loci influencing compactness, carotene content and FAC were common to both populations, while others were specific to particular genetic backgrounds. It is hoped that the QTLs identified will be useful tools for marker-assisted selection and accelerate the identification of desirable genotypes for breeding
Fine-mapping and cross-validation of QTLs linked to fatty acid composition in multiple independent interspecific crosses of oil palm
Background - The commercial oil palm (Elaeis guineensis Jacq.) produces a mesocarp oil (commonly called ‘palm oil’) with approximately equal proportions of saturated and unsaturated fatty acids (FAs). An increase in unsaturated FAs content or iodine value (IV) as a measure of the degree of unsaturation would help to open up new markets for the oil. One way to manipulate the fatty acid composition (FAC) in palm oil is through introgression of favourable alleles from the American oil palm, E. oleifera, which has a more unsaturated oil.Results - In this study, a segregating E. oleifera x E. guineensis (OxG) hybrid population for FAC is used to identify quantitative trait loci (QTLs) linked to IV and various FAs. QTL analysis revealed 10 major and two putative QTLs for IV and six FAs, C14:0, C16:0, C16:1, C18:0, C18:1 and C18:2 distributed across six linkage groups (LGs), OT1, T2, T3, OT4, OT6 and T9. The major QTLs for IV and C16:0 on LGOT1 explained 60.0 – 69.0 % of the phenotypic trait variation and were validated in two independent BC2 populations. The genomic interval contains several key structural genes in the FA and oil biosynthesis pathways such as PATE/FATB, HIBCH, BASS2, LACS4 and DGAT1 and also a relevant transcription factor (TF), WRI1. The literature suggests that some of these genes can exhibit pleiotropic effects in the regulatory networks of these traits. Using the whole genome sequence data, markers tightly linked to the candidate genes were also developed. Clustering trait values according to the allelic forms of these candidate markers revealed significant differences in the IV and FAs of the palms in the mapping and validation crosses.Conclusions - The candidate gene approach described and exploited here is useful to identify the potential causal genes linked to FAC and can be adopted for marker-assisted selection (MAS) in oil palm<br/
Vítězslava Kaprálová - searching for one's own way: Partita for a string orchestra and piano op. 20, Concerto for violin, clarinet and orchestra op. 21
Univerzita Karlova Filozoficka fakulta Ustav hudebni vedy Obor: Hudebni veda Diplomova prace Autor: Michaela Janouskova Vitezslava Kapnilova - hledani vlastni cesty Partita pro klavir a smyccovy- orchestr Ope 20 Concertino pro housle, klarinet a orchestr Ope 21 Praze Knihovna ustavu hlldebni Filozoficke faku mlm. J. Palsons 2, Prana 11638 Vedouci diplomove prace: Prof. PhDr. MgA. Milan SlavickJ Oponent diplomove prace: Prof PhDr. Jarmila Gabrielova esc. Datum odevzdani diplomove prace: srpen 2007 Uvod Kapitola III OBSAH Partita pro smyccory orchestr a klavir Ope 20 Kapitola 112 Partita pro smyccory orchestr a klavir Ope 20 - analyza Kapitola 1111 Concertino pro housIe, klarinet a orchestr Ope 21 Kapitola 1112 Concertino pro housIe, klarinet a orchestr Ope 21 - analyza Kapitola III s. 1 - 3 s. 4-7 s.8 - 27 s. 28 - 33 s. 34 - 50 s. 51- 67 Tre Ricercari Bohusiava Martinu a jejich vliv na utvareni noveho ryrazu orchestrainich del VitezsIavy Kapralove Kapitola IV s. 68 - 74 Partita a Concertino v kontextu del VitezsIavy Kapralove Zaver s. 75 - 76 Literatura s. 77 - 78 Pfilohy s. 79 - 89 Prohlasuji, ze jsem diplomovou praci vypracovala samostatne a pouzila vYhradne citovanych pramenu. Souhlasim s pujcovarnm teto pnice ke studijnim ucelum. Uvod Jak napovida jiz sam nazev, bude rna prace venovana skladatelce..