Sunflower and Palm Kernel Meal Present Bioaccessible Compounds after Digestion with Antioxidant Activity.

Sunflower (Helianthus annuus L.) and African palm kernel (Elaeis guineensis Jacq.) are among the most cultivated in the world regarding oil extraction. The oil industry generates a large amount of meal as a by-product, which can be a source of nutrients and bioactive compounds. However, the physiological effects of bioactive compounds in such matrices are only valid if they remain bioavailable and bioactive after simulated gastrointestinal digestion. This study evaluated the chemical composition and antioxidant and prebiotic potential of de-oiled sunflower (DS) and de-oiled palm kernel (DP) meal after in vitro digestion. The DS sample had the highest protein content and the best chemical score, in which lysine was the limiting amino acid. Digested samples showed increased antioxidant activity, measured by in vitro methods. The digested DS sample showed a better antioxidant effect compared to DP. Moreover, both samples managed to preserve DNA supercoiling in the presence of the oxidizing agent. The insoluble fractions after digestion stimulated the growth of prebiotic bacterium, similar to inulin. In conclusion, simulated gastrointestinal digestion promoted in both matrices an increase in protein bioaccessibility and antioxidant capacity, pointing to a metabolic modulation favorable to the organism.

Transcriptomic analysis of mesocarp tissue during fruit development of the oil palm revealed specific isozymes related to starch metabolism that control oil yield.

The oil palm (Elaeis guineensis Jacq.) produces a large amount of oil from the fruit. However, increasing the oil production in this fruit is still challenging. A recent study has shown that starch metabolism is essential for oil synthesis in fruit-producing species. Therefore, the transcriptomic analysis by RNA-seq was performed to observe gene expression alteration related to starch metabolism genes throughout the maturity stages of oil palm fruit with different oil yields. Gene expression profiles were examined with three different oil yields group (low, medium, and high) at six fruit development phases (4, 8, 12, 16, 20, and 22 weeks after pollination). We successfully identified and analyzed differentially expressed genes in oil palm mesocarps during development. The results showed that the transcriptome profile for each developmental phase was unique. Sucrose flux to the mesocarp tissue, rapid starch turnover, and high glycolytic activity have been identified as critical factors for oil production in oil palms. For starch metabolism and the glycolytic pathway, we identified specific gene expressions of enzyme isoforms (isozymes) that correlated with oil production, which may determine the oil content. This study provides valuable information for creating new high-oil-yielding palm varieties via breeding programs or genome editing approaches.

Soil physicochemical properties change by age of the oil palm crop.

For decades there have been controversies related to the changes generated by oil palm plantations in the physicochemical properties of the soil, soil biota, and ecological interactions. Therefore, the present investigation evaluated root diameter and biomass at three ages of oil palm cultivation. Besides, we evaluated the effect of the ages on the physicochemical parameters of the soil in comparison with pasture plots. To know the diameter, fresh, and dry biomass of roots, soil sampling was carried out around the oil palm (3-, 5-, and 15-years-old) at distances of 1, 2, and 3 m from the trunk plant. Also, to know the changes in the properties of the soil, the sampling was carried out randomly in the same plots and the pasture plot (control). The results showed that both the diameter and the fresh and dry root biomass increased in 15-year-old plantations compared with 3- and 5-year-old. In addition, correlation analysis and principal component analysis indicated that the parameters evaluated are associated with the adult age of the oil palm. Also, the results of soil physicochemical showed that low soil fertility was associated with an increase in the age of the palm.

Leaf concentration of macronutrients in oil palm plants fertilized with phosphorus, potassium and magnesium in the Eastern Amazon

The concentrations of nutrients in the leaves allow a better understanding of the nutritional status of oil palm plants, making it a tool for diagnosing the origins of nutritional problems and assisting in fertilizer recommendations. In this sense, the objective of the current research was to evaluate the leaf concentrations of N, P, K, Ca, Mg and S in the oil palm under fertilization with phosphate, potassium and magnesium in edaphoclimatic conditions of Eastern Amazon. The experiment was conducted at the AGROPALMA® Company in the municipality of Tailândia, state of Pará, Brazil. The experimental design used was randomized blocks in a factorial scheme 4 x 2 x 3 x 2, with four levels of phosphorus, two sources of phosphorus (natural phosphate and triple superphosphate), three levels of potassium and two levels of magnesium. Phosphorus fertilization increased the leaf concentrations of N, P, Ca and Mg, providing higher levels when triple superphosphate was applied. However, in adult oil palm plants (12 years old), there was different on leaf concentrations of N, P, K and S between phosphorus sources aphid. Potassium and magnesium fertilization only increased the leaf concentrations of K and Mg, respectively. Fertilization with P, K and Mg promotes adequate leaf concentrations of K, Ca, Mg e S in oil palm plants grown in the Eastern Amazon.

Flavonoid Composition and Pharmacological Properties of Elaeis guineensis Jacq. Leaf Extracts: A Systematic Review.

The oil palm tree (Elaeis guineensis Jacq.) originates from West and Central Africa, and it is cultivated in Malaysia for its oil-producing fruits. Malaysia is the world's second largest palm oil producer and the world's largest exporter to date. Consequently, the Malaysian oil palm industry constantly generates a huge amount of biomass with the major contributor being the leaves. A large percentage of these leaves remain underutilized, making them a promising source of raw materials that can be converted into value-added products. The present review summarizes and discusses the flavonoid composition, total phenolic and flavonoid content, and the in vitro and in vivo pharmacological properties exhibited by the extracts of the leaves of E. guineensis. The purpose of this systematic review is to highlight the potential of valorizing the leaf extracts of the oil palm tree as pharmaceutical and cosmeceutical agents.

Identification of Oil Palm's Consistently Upregulated Genes during Early Infections of Ganoderma boninense via RNA-Seq Technology and Real-Time Quantitative PCR.

Basal stem rot (BSR) disease caused by pathogenic fungus Ganoderma boninense is a significant concern in the oil palm industry. G. boninense infection in oil palm induces defense-related genes. To understand oil palm defense mechanisms in response to fungal invasion, we analyzed differentially expressed genes (DEGs) derived from RNA-sequencing (RNA-seq) transcriptomic libraries of oil palm roots infected with G. boninense. A total of 126 DEGs were detected from the transcriptomic libraries of G. boninense-infected root tissues at different infection stages. Functional annotation via pathway enrichment analyses revealed that the DEGs were involved in the defense response against the pathogen. The expression of the selected DEGs was further confirmed using real-time quantitative PCR (qPCR) on independent oil palm seedlings and mature palm samples. Seven putative defense-related DEGs consistently showed upregulation in seedlings and mature plants during G. boninense infection. These seven genes might potentially be developed as biomarkers for the early detection of BSR in oil palm.

Detection of ploidy and chromosomal aberrations in commercial oil palm using high-throughput SNP markers.

MAIN CONCLUSION: Karyotyping using high-density genome-wide SNP markers identified various chromosomal aberrations in oil palm (Elaeis guineensis Jacq.) with supporting evidence from the 2C DNA content measurements (determined using FCM) and chromosome counts. Oil palm produces a quarter of the world's total vegetable oil. In line with its global importance, an initiative to sequence the oil palm genome was carried out successfully, producing huge amounts of sequence information, allowing SNP discovery. High-capacity SNP genotyping platforms have been widely used for marker-trait association studies in oil palm. Besides genotyping, a SNP array is also an attractive tool for understanding aberrations in chromosome inheritance. Exploiting this, the present study utilized chromosome-wide SNP allelic distributions to determine the ploidy composition of over 1,000 oil palms from a commercial F1 family, including 197 derived from twin-embryo seeds. Our method consisted of an inspection of the allelic intensity ratio using SNP markers. For palms with a shifted or abnormal distribution ratio, the SNP allelic frequencies were plotted along the pseudo-chromosomes. This method proved to be efficient in identifying whole genome duplication (triploids) and aneuploidy. We also detected several loss of heterozygosity regions which may indicate small chromosomal deletions and/or inheritance of identical by descent regions from both parents. The SNP analysis was validated by flow cytometry and chromosome counts. The triploids were all derived from twin-embryo seeds. This is the first report on the efficiency and reliability of SNP array data for karyotyping oil palm chromosomes, as an alternative to the conventional cytogenetic technique. Information on the ploidy composition and chromosomal structural variation can help to better understand the genetic makeup of samples and lead to a more robust interpretation of the genomic data in marker-trait association analyses.

Metabolite Characterization and Correlations with Antioxidant and Wound Healing Properties of Oil Palm (Elaeis guineensis Jacq.) Leaflets via 1H-NMR-Based Metabolomics Approach.

Oil palm (Elaeis guineensis Jacq.) leaflets (OPLs) are one of the major agricultural by-products generated from the massive cultivation of Malaysian palm oil. This biomass is also reported to be of potential value based on its health-improving effects. By employing proton nuclear magnetic resonance (1H-NMR) spectroscopy combined with multivariate data analysis (MVDA), the metabolite profile of OPLs was characterized and correlated with their antioxidant and wound healing properties. Principal component analysis (PCA) classified four varieties of extracts, prepared using solvents ranging from polar to medium polarity, into three distinct clusters. Cumulatively, six flavonoids, eight organic acids, four carbohydrates, and an amine were identified from the solvent extracts. The more polar extracts, such as, the ethyl acetate-methanol, absolute methanol, and methanol-water, were richer in phytochemicals. Based on partial least square (PLS) analysis, the constituents in these extracts, such as (+)-catechin, (-)-epicatechin, orientin, isoorientin, vitexin, and isovitexin, were strongly correlated with the measured antioxidant activities, comprising ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitric oxide (NO) free radical scavenging activities, as well as with cell proliferation and migration activities. This study has provided crucial evidence on the importance of these natural antioxidant compounds on the wound healing properties of OPL.

In Vitro Wound Healing Potential of Flavonoid C-Glycosides from Oil Palm (Elaeis guineensis Jacq.) Leaves on 3T3 Fibroblast Cells.

Oil palm (Elaeis guineensis Jacq.) leaves (OPL) are widely available at zero cost in Southeast Asia countries, especially in Malaysia and Indonesia due to large scale oil palm plantations. OPLs contain a large amount of flavonoids in particular flavonoid C-glycosides, which are known to possess useful biological properties including antioxidant and wound healing properties. The present study aimed at evaluating the wound healing efficacy of OPL in various solvent extracts and flavonoid enriched fractions and to determine the contribution of flavonoid C-glycosides (orientin, isoorientin, vitexin and isovitexin) using in-vitro scratch assay on 3T3 fibroblast cells. Solvent crude extracts with different polarity were screened and the most active extract was subjected to acid hydrolysis. The crude and acid hydrolysed extracts were further enriched using macroporous resins, XAD7HP. UHPLC-UV/PDA and LC-MS/MS analysis were applied for identification and confirmation of flavonoid C-glycosides. The wound healing properties comprised of cell viability, cell proliferation and cell migration were studied. Allantoin was used as a positive control to compare the efficacy among the tested samples. The results revealed all OPL crude extracts, flavonoid enriched fractions and flavonoid C-glycosides were non-toxic at concentrations below 25 µg/mL and showed better cell proliferation and migration activities at low concentrations than higher concentrations.. This study also demonstrated orientin, isoorientin, vitexin and isovitexin presented in OPL extracts and flavonoid enriched fractions stimulated proliferation and migration of 3T3 fibroblast cells. Hence, these findings may pose potential therapeutic bioactive agents for wound healing by enhancing fibroblast proliferation and migration.

Adsorption and Desorption Properties of Total Flavonoids from Oil Palm (Elaeis guineensis Jacq.) Mature Leaf on Macroporous Adsorption Resins.

Three different macroporous resins (XAD7HP, DAX-8, and XAD4) were evaluated for their adsorption and desorption properties in preparing flavonoid-enriched oil palm (Elaeis guineensis Jacq.) leaf extract. The influences of initial concentration, solution pH, contact time, and desorption solvent (ethanol) concentration were determined by static sorption/desorption methods. The optimal condition for adsorption of flavonoids was achieved when the solution of the extract was adjusted to pH 7, reaching equilibrium after 1440 min at 298 K. The adsorption process was well described by a pseudo-second-order kinetics model, while the adsorption isotherm data fitted well with a Freundlich model. The adsorption by each resin was via an exothermic and physical adsorption process. Based on the static experiment results, XAD7HP was found to be the most appropriate adsorbent, while 80% ethanol was the best solvent for desorbent. Further evaluation of its dynamic adsorption and desorption characteristics on a packed glass column showed that XAD7HP could enrich the OPL total flavonoid content by a 3.57-fold increment. Moreover, UHPLC-UV/PDA and UHPLC-MS/MS analysis revealed that apigenin and luteolin derivatives were selectively adsorbed by XAD7HP. Additionally, both the crude OPL extract and the flavonoid-enriched fraction have good DPPH and NO free radical scavenging activities. Multiple interactions between the flavonoids and cross-linked polymeric XAD7HP resin through van der Waals forces and hydrogen bonding described the sorption processes. Therefore, by utilizing this method, the flavonoid-enriched fraction from crude OPL extract could be used as a potential bioactive ingredient in nutraceutical and pharmaceutical applications at minimum cost with optimum efficiency.

Tissue Culture of Oil Palm: Finding the Balance Between Mass Propagation and Somaclonal Variation.

The oil palm (Elaeis guineensis Jacq.) is typically propagated in vitro by indirect somatic embryogenesis, a process in which somatic cells of an explant of choice are, via an intermediate phase of callus growth, induced to differentiate into somatic embryos. The architecture of the oil palm, lacking axillary shoots, does not allow for vegetative propagation. Therefore, somatic embryogenesis is the only alternative to seed propagation, which is hampered by long germination times and low germination rates, for the production of planting material. The current oil palm somatic embryogenesis procedure is associated with several difficulties, which are described in this review. The limited availability of explants, combined with low somatic embryo initiation and regeneration rates, necessitate the proliferation of embryogenic structures, increasing the risk for somaclonal variants such as the mantled phenotype. Several ways to improve the efficiency of the tissue culture method and to reduce the risk of somaclonal variation are described. These include the use of alternative explants and propagation techniques, the introduction of specific embryo maturation treatments and the detection of the mantled abnormality in an early stage. These methods have not yet been fully explored and provide interesting research field for the future. The development of an efficient oil palm micropropagation protocol is needed to keep up with the increasing demand for palm oil in a sustainable way. Mass production of selected, high-yielding palms by tissue culture could raise yields on existing plantations, reducing the need for further expansion of the cultivated area, which is often associated with negative environmental impacts.

Histodifferentiation of oil palm somatic embryo development at low auxin concentration.

Large-scale propagation of oil palm (Elaeis guineensis, Jacq.) is difficult due to its single apical meristem. Thus, obtaining plants is mainly through seed germination, and a long growing period is required before oil production is possible. An alternative to large-scale seedling production is indirect somatic embryogenesis. The aim of this study was to analyze the somatic embryogenesis process in oil palm (E. guineensis Jacq.) with amino acids and low concentrations of auxins. The Tenera hybrid was analyzed by cytochemical and ultrastructural methods and was used to regenerate oil palm plants. First, calli were induced in MS culture media supplemented with 2,4-D and picloram. Two types of calli were obtained, characterized by beige or translucent color. Beige calli had embryogenic characteristics, such as large nuclei with prominent nucleoli, and they were multiplied for 8 months in MM culture (half strength MS, 1 mg L-1 2,4-D, 2 mg L-1 2iP, 1 mg L-1 IBA, 250 mg L-1 citric acid, 10 mg L-1 cysteine, 100 mg L-1 inositol, 1 mg L-1 thiamine, 1 mg L-1 pyridoxine, 1 mg L-1 nicotinic acid, 1 mg L-1 glycine, 200 mg L-1 malt extract, and 100 mg L-1 casein hydrolysate). After multiplication, the MCB culture medium (half strength MS, supplemented with 0.25 mg L-1 NAA, 2 mg L-1 BAP, MM vitamins and 200 mg L-1 malt extract, and 100 mg L-1 casein hydrolysate) was the most efficient for embryo formation, showing meristematic centers with totipotent cells in histochemical analyses. The somatic embryos were developed and germinated in MG medium (half strength MS, 0.45 mg L-1 IAA, 0.25 mg L-1 BAP, and MM vitamins), transplanted into polyethylene tubes containing pine bark substrates, and acclimatized in a greenhouse, achieving a 97% survival rate. The use of picloram for callus induction and somatic embryogenesis is advantageous and multiplication in MM medium is an important step for increasing cell mass. The calli with light beige color and nodular structures have meristematic cells with dense cytoplasm and totipotential features that later give rise to protoderm, procambium, and ground meristem during the globular, cordiform, and torpedo embryogenesis phases. In MCB medium, the concentration of vitamins and amino acids are crucial for somatic embryogenesis.

Identificación de estructuras de infección de Phytophthora palmivora en hojas de clones de palma de aceite Elaeis guinennsis Jacq / Identification of infection structures of Phytophthora palmivora in leaves of oil palm clones Elaeis guineensis Jacq

Este trabajo investigó el modelo de interacción planta-patógeno mediante discos de hojas de clones de palma de aceite inoculados en condiciones ex situ con un aislamiento de Phytophthora palmivora. Las inoculaciones se realizaron en condiciones controladas en cámara de crecimiento. En total, seis diferentes ortets fueron evaluados en seis tiempos de infección (2, 4, 6, 12, 24 y 48 horas postinfección, o hpi). Se determinó la presencia de estructuras de patogenicidad de P. palmivora como quiste, apresorio y tubos germinativos. Los quistes fueron identificados principalmente a las 2, 4 y 6 hpi. A partir de las 48 hpi no hubo presencia de zoosporas enquistadas para ningún ortet evaluado. En cuanto a los apresorios, estos se empezaron a desarrollar a las 4 horas de realizada la inoculación (siendo las 12 y 24 hpi los tiempos de mayor registro de estas estructuras). 121 Identificación de estructuras de infección de Phytophthora palmivora en hojas de clones de palma de aceite (Elaeis guineensis Jacq.) Méndez, K. et al. Introducción La Pudrición del cogollo (pc) es una de las principales enfermedades que afecta al cultivo de palma de aceite, destruyendo plantaciones desde 1964. En Colombia la enfermedad se presenta en las cuatro zonas palmeras y ha alcanzado proporciones epidémicas (Sarria et al., 2013a, 2016). A finales de 2004 en la Zona Suroccidental se registró un incremento en el número de casos, con un crecimiento exponencial de esta enfermedad, y a partir de 2007 se vieron afectadas más de 30.000 ha de cultivos de palma de aceite. En la Zona Central un comportamiento similar de la enfermedad fue registrado para la región de Puerto Wilches (Norte de Santander) entre 2009 y 2013, periodo en el cual se perdieron más de 40.000 ha como consecuencia de una epidemia de pc (Sanz, 2016). Por su parte, los productores de la Zona Norte actualmente hacen frente a la amenaza de una expansión epidémica de la pc con síntoma de hoja clorótica, la cual da cuenta de un estado avanzado de la enfermedad. Una amplia revisión del impacto de esta enfermedad desde sus inicios se encuentra en Benítez & García (2015), Sundram & Intan-Nur (2017) y Torres et al. (2016). La enfermedad de la Pudrición del cogollo es causada por el oomiceto hemibiótrofo P. palmivora (Sarria et al., 2008, 2013). Desde su identificación como agente causal de la pc en 2008, el Centro de Investigación en Palma de Aceite (Cenipalma) ha liderado diferentes investigaciones que han dado como resultado el desarrollo de estrategias de manejo integrado del cultivo de palma, así como la descripción del patógeno por medio de inoculación en condiciones in vitro en foliolos inmaduros de palma (Martínez et al., 2013, 2014a), entre otras. En cuanto a la presencia de esta enfermedad en otros cultivos, Mohamed-Azni et al. (2017) emplearon la técnica de foliolo inmaduro, logrando infectar foliolos de palma de aceite con P. palmivora aislada proveniente de cultivos de cacao y durián. Teniendo en cuenta que actualmente no se conocen fuentes probadas de resistencia de cultivares de Elaeis guineensis a la pc, y que un ciclo de mejoramiento genético de palma puede durar más de 25 años Por su parte, los tubos germinativos se encontraron a partir de las 48 hpi únicamente. Finalmente, se pudo establecer que el patógeno logra colonizar tejidos de foliolo no lignificados de clones de palma. Además, se encontró una relación entre el número de estructuras del patógeno con el comportamiento del cultivar de la palma donor (ramet)

Plant-pathogen model interaction was studied using leaf disks of oil palm clones inoculated ex situ with a Phytophthora palmivora isolate. The inoculation process was performed under growth chamber conditions. Six ortets were evaluated at six post-inoculation times (2, 4, 6, 12, 24 y 48 hours post infection, or hpi). Pathogen's infection structures as cyst, apressorium and germinative tubes were found. Cysts were identified mainly at 2, 4 and 6 hpi. After 48 hpi there were not any cysts for the evaluated ortets. The apresoria started to develop at 4 hpi, with the highest presence of these structures at 12 and 24 hpi. Germinative tubes were found only after 48 hpi. Therefore, it was established that the pathogen can colonize no-lignified tissue of oil palm clones. Finally, we found a relation between the pathogen's structures number and the response of the ortet related to its susceptibility and resistance response. Thus, it was found that the susceptible cultivar showed the highest number of germinative tubes

Identification of a Δ12 fatty acid desaturase from oil palm (Elaeis guineensis Jacq.) involved in the biosynthesis of linoleic acid by heterologous expression in Saccharomyces cerevisiae.

Oil palm (Elaeis guineensis Jacq.) is one of the highest oil-yield crops in the world. A Δ12-desaturases associated with the primary steps of long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis were successfully cloned from oil palm and their functions identified. The open reading frames (ORFs) of egFAD2 (GenBank accession: KT023602) consisted of 1176bp and code for 391 amino acids. Their deduced polypeptides showed 75-93% identity to microsomal Δ12-desaturases from other higher plants, and each contained the three histidine clusters typical of the catalytic domains of such enzymes. RT-PCR experiment indicated that the egFAD2 gene exhibited the highest accumulation in the mesocarp of fruits at 120-140 DAP (i.e. the fourth period of fruit development) and, despite having different expression levels, the other four stages were at significantly lower levels compared with the fourth stage. Plasmid pYES2-egFAD2 was transformed into Saccharomyces cerevisiae strain INVSc1 using lithium acetate method for expression under the induction of galactose. Yeast cells transformed with plasmid constructs containing egFAD12 produced an appreciable amount of linoleic acids (18:2(Δ9,)(12)), not normally present in wild-type yeast cells, indicating that the genes encoded functional Δ12-desaturase enzymes.

Performance of feedlot lambs fed palm kernel cake-based diets.

Fifty-four castrated male lambs with an average body weight of 23 ± 0.35 kg were randomly assigned to five treatments that consisted of different levels of palm kernel cake in the diet (0.0, 7.5, 15.0, 22.5, and 30.0 % on a DM basis) in order to evaluate the effects on intake, digestibility, empty body weight, and body gain composition. The intakes of dry matter, organic matter, crude protein, and non-fiber carbohydrates (NFC) presented with a decreasing linear effect. However, the intakes of EE and NDF presented with increased linear results as the palm kernel cake was added to the concentrate. There was a quadratic effect for the digestibility coefficient of all nutrients, except for NFC. The palm kernel cake had a decreasing linear effect on final body weight, empty body weight, and the average daily gain of the animals that were fed increased levels of palm kernel cake. The inclusion of palm kernel cake as a partial substitute for concentrate decreases the intake of the majority of nutrients, except for EE and NDF, and consequently, causes deleterious effects on the nutrient digestibility and performance of lambs that are fed a 50:50 roughage/concentrate ratio.

Molecular defense response of oil palm to Ganoderma infection.

Basal stem rot (BSR) of oil palm roots is due to the invasion of fungal mycelia of Ganoderma species which spreads to the bole of the stem. In addition to root contact, BSR can also spread by airborne basidiospores. These fungi are able to break down cell wall components including lignin. BSR not only decreases oil yield, it also causes the stands to collapse thus causing severe economic loss to the oil palm industry. The transmission and mode of action of Ganoderma, its interactions with oil palm as a hemibiotroph, and the molecular defence responses of oil palm to the infection of Ganoderma boninense in BSR are reviewed, based on the transcript profiles of infected oil palms. The knowledge gaps that need to be filled in oil palm-Ganoderma molecular interactions i.e. the associations of hypersensitive reaction (HR)-induced cell death and reactive oxygen species (ROS) kinetics to the susceptibility of oil palm to Ganoderma spp., the interactions of phytohormones (salicylate, jasmonate and ethylene) at early and late stages of BSR, and cell wall strengthening through increased production of guaiacyl (G)-type lignin, are also discussed.

Diversidad y estructura genética de accesiones de palma de aceite (Elaeis guineesis Jacq.)provenientes de Camerún / Diversity and genetic structure of oil palm accession (Elaeis guineesis Jacq.) from Cameroon

La palma de aceite Elaeis guineesis Jacq. posee gran importancia debido al aceite que se extrae de sus frutos, del cual se obtienen derivados refinados de gran valor comercial como el biodiesel, entre otros. Esta investigación buscó determinar la estructura y diversidad genética de 311 muestras de palma de aceite proveniente de la República de Camerún mediante 10 marcadores microsatélite. Los resultados mostraron valores promedio para el número medio de alelos por locus de Na=8.433 y un número efectivo de alelos por locus de Ne=4.756; las diferencias entre estos valores permiten inferir que los 106 alelos encontrados para estas poblaciones son considerados alelos raros. Adicionalmente, el valor de diversidad genética fue alto (valor medio de He= 0.781) respecto a reportes de varios autores. La varianza molecular obtenida evidenció que el mayor porcentaje (80 %) se encuentra dentro de los individuos. Los análisis mostraron que no se definió ningún tipo de estructura poblacional, lo que permitió inferir un alto flujo genético entre las zonas geográficas, esto corroborado por los altos valores de diversidad genética obtenidos. Los 311 genotipos evaluados fueron definidos como una población natural heterogénea heterocigota, apta para favorecer el aumento de la base genética de las poblaciones cultivadas de palma de aceite.

Oil palm Elaeis guineesis Jacq. is of great importance because of the oil extracted from its fruits, whose refined derivatives are commercially valuable as biodiesel, among others uses. This study sought to determine the structure and genetic diversity of 311 oil palm samples from the Republic of Cameroon with 10 microsatellite markers. The results showed values for the average number of alleles per locus of Na= 8.433 and effective number of alleles per locus of Ne= 4.756; from the differences between these values, it can be inferred that the 106 alleles found for these populations could be considered rare alleles. Additionally the value of genetic diversity was high (mean value of He= 0.781) compared to reports of several authors. The obtained molecular variance showed that the highest percentage (80 %) was found within the individuals. The analysis did not show any defined population structure, which allowed us to infer a high gene flow among the geographic zones, corroborated it by the high genetic diversity values obtained. The 311 genotypes were defined as a heterogeneous heterozygous natural population suitable to increase the genetic base of oil palm cultivated populations.

Selection among and within and combined selection in oil palm families derived from Dura x Dura / Seleção entre e dentro e seleção combinada em famílias de dendê oriundas do cruzamento Dura x Dura

Oil palm, in view of the worldwide consumed oil, is a perennial crop of great importance. Nevertheless, the genetic improvement is still incipient. In this study we applied the selection among and within families and the combined selection, based on the phenotypic values and phenotypic performance (Pi statistic), to verify which strategy obtained the highest genetic gains. Five full-sib families were evaluated in randomized blocks, with five replicates and 12 plants per plot, over five years of successive harvests. The total number of bunches and the total fruit yield per year plant-1 were evaluated. Values of 1.00 and 0.25 for the ratio between the environmental variance among plots and the environmental variance among plants within the plot for both traits, respectively, were adequate for the estimation of the genetic parameters. The existence of genetic variability in the population Dura was verified for both evaluated traits. The combined selection, based either on the phenotypic values or on the underlying Pi statistic, resulted in the highest genetic gains. Despite the satisfactory gains since it translates the true yield potential of the evaluated genotypes and their performance stability.

O dendê é uma cultura perene de grande importância devido à produção de óleo que é consumido mundialmente. Contudo, o melhoramento genético ainda é incipiente. Neste trabalho foram utilizadas a seleção entre e dentro de famílias e a seleção combinada, a partir dos valores fenotípicos e da performance fenotípica (estatística Pi), visando verificar com qual das estratégias foi obtido maior ganho genético. Avaliaram-se cinco famílias de irmãos-completos em blocos casualizados, com cinco repetições e 12 plantas por parcela, durante cinco anos de colheitas sucessivas. O número total de cachos e a produção total de frutos por ano planta-1 foram avaliados. Valores de 1,00 e 0,25 para a razão entre a variância ambiental entre parcelas e a variância ambiental entre plantas dentro da parcela, respectivamente para ambas as características, foram adequados para a estimação dos parâmetros genéticos. Verificou-se a existência de variabilidade genética na população Dura para as duas características avaliadas. A seleção combinada, tanto baseada nos valores fenotípicos ou fundamentada na estatística Pi, proporcionou maiores ganhos genéticos. Embora a seleção entre e dentro de famílias tenha proporcionado ganhos satisfatórios, recomenda-se o processo de seleção baseado na estatística Pi, pois a mesma irá traduzir o verdadeiro potencial produtivo dos genótipos avaliados e a sua estabilidade de comportamento.