Mannans: Structural carbohydrates produced during seed maturation in Euterpe edulis Martius, an Atlantic Forest species vulnerable to extinction.

Palm seedlings are visually selected from mature fruits in a slow process that leads to nonuniform germination and high embryo mortality. In this study, we determined the levels of monosaccharides, their crystallinity, and their role in the formation of Euterpe edulis endosperm during seed maturation. Seeds harvested from 108 to 262 days after anthesis (DAA) were analyzed morphologically, physiologically, and chemically to measure soluble and insoluble lignins, ashes, structural carbohydrates, degree of crystallinity, and endo-ß-mannanase. The seeds achieved maximum germination and vigor at 164 DAA. During the early stages, only compounds with a low structural order were formed. The contents of soluble and insoluble lignins, ashes, glucans, and galactans decreased during maturation. Those of mannans, the main structural carbohydrate in the endosperm, increased along with the degree of crystallinity, as suggested by a mannan-I-type X-ray diffraction pattern. Similarly, endo-ß-mannanase activity peaked at 262 DAA. The superior physiological outcome of seeds and seedlings at 164 DAA implies a 98-day shorter harvesting time. The state of mannans during seed maturation could be used as a marker to improve seedling production by E. edulis.

Adaptación al sotobosque de una comunidad de palmas (Arecaceae) andinas desde la perspectiva de las tasas vitales / Adaptation to the undergrowth of a community of Andean palms (Arecaceae) from the vital rates perspective

Introducción: Las palmas tienen adaptaciones para prosperar en el entorno limitante del sotobosque, que se pueden examinar a partir del estudio de las tasas de supervivencia, crecimiento y fecundidad. Sin embargo, los estudios que abordan las estrategias de tasas vitales desarrolladas por una comunidad de palmas para habitar el sotobosque del bosque son escasos. Objetivo: Determinar y comparar las tasas vitales de supervivencia, crecimiento y fertilidad en una comunidad de palmas de sotobosque andino. Métodos: El estudio se realizó en el Parque Natural Chicaque, Colombia. En un área de 0.07 ha, donde se estudiaron las especies Chamaedorea linearis, C. pinnatifrons, Geonoma orbignyana y G. undata. Durante 2018 a 2019 se recolectaron datos correspondientes a supervivencia, crecimiento y fecundidad. Las tasas vitales se estimaron a partir de su relación con el tamaño de los individuos. Resultados: Se registraron un total de 597, 687, 453 y 690 individuos en 0.1 ha de C. linearis, C. pinnatifrons, G. orbignyana y G. undata, respectivamente. Las cuatro especies tuvieron una alta supervivencia de plántulas, bajas tasas de crecimiento en individuos sin tallo, baja producción de hojas, pocas hojas totales, una alta longevidad de las hojas, e inicio de la reproducción con un tallo de baja altura. No obstante, hubo diferencias entre las especies en las que G. orbignyana y C. pinnatifrons presentaron patrones comúnmente vistos en las palmas del sotobosque. Por el contrario, C. linearis y G. undata tienen estrategias de crecimiento mixtas para hacer frente a los espacios abiertos y las condiciones del sotobosque, ya que sus hojas y copas son más grandes, tienen mayores tasas de crecimiento del tallo y la reproducción comienza a mayor altura. En cuanto a los géneros, las Chamaedoreas tuvieron unas tasas de crecimiento y reproducción altas, pasando la mayor parte de su vida como adultos. Por su parte, las Geonomas priorizan la permanencia de los individuos, con sus ciclos de vida largos, tasas de crecimiento más bajas. Conclusiones: Las Chamaedoreas priorizan crecimiento y reproducción, mientras que las Geonomas priorizan la permanencia. Las condiciones limitantes del sotobosque parecen favorecer estas dos estrategias de crecimiento típicas de las especies estudiadas. Estos resultados pueden considerarse como un paso hacia el conocimiento de las estrategias de la coexistencia de las comunidades de palmeras en los bosques.

Introduction: Palms have adaptations to thrive in the limiting environment of the understory, which can be examined from studying their survival, growth and fecundity rates. However, studies that address the vital rates strategies developed by a community of palms to successfully inhabit the forest understory are scarce. Objective: To determine and compare the vital rates of survival, growth and fecundity in a community of Andean understory palms. Methods: The study was carried out in the Chicaque Natural Park, Colombia in an area occupying 0.07 ha, focused on the species Chamaedorea linearis, C. pinnatifrons, Geonoma orbignyana and G. undata. During 2018 and 2019, data corresponding to survival, growth and fecundity of these species were collected. The vital rates were estimated from their relationship with the size of the individuals. Results: A total of 597, 687, 453 and 690 individuals were registered in 0.1 ha of C. linearis, C. pinnatifrons, G. orbignyana and G. undata, respectively. The four species had high survival of seedlings, low growth rates in stemless individuals, low leaf production, few total leaves, a high longevity of the leaves and start of reproduction with low-height aerial stem. However, we found differences among species in which G. orbignyana and C. pinnatifrons demonstrated patterns commonly seen in understory palms. By contrast, C. linearis and G. undata had mixed growth strategies to cope with open spaces and understory conditions, as their leaves are larger, have larger stem growth rates and reproduction begins at a higher height. In terms of the genera, Chamaedoreas had fast growth and reproduction rates, spending most of their lives as adults. Meanwhile, Geonomas prioritizes the stasis of individuals, with its long-life cycles and lower growth rates. Conclusions: Chamaedoreas prioritizes growth and reproduction, while Geonomas prioritizes stasis. The limiting conditions of the understory seem to favor these two growth strategies in the species. These results can be considered as a step towards better understanding the strategies of a community of palms in the understory.

Transcriptome analysis reveals key developmental and metabolic regulatory aspects of oil palm (Elaeis guineensis Jacq.) during zygotic embryo development.

BACKGROUND: Oil palm is the most efficient oil-producing crop in the world, and the yield of palm oil is associated with embryonic development. However, a comprehensive understanding of zygotic embryo development at the molecular level remains elusive. In order to address this issue, we report the transcriptomic analysis of zygotic embryo development in oil palm, specifically focusing on regulatory genes involved in important biological pathways. RESULTS: In this study, three cDNA libraries were prepared from embryos at S1 (early-stage), S2 (middle-stage), and S3 (late-stage). There were 16,367, 16,500, and 18,012 genes characterized at the S1, S2, and S3 stages of embryonic development, respectively. A total of 1522, 2698, and 142 genes were differentially expressed in S1 vs S2, S1 vs S3, and S2 vs S3, respectively. Using Gene Ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis to identify key genes and pathways. In the hormone signaling pathway, genes related to auxin antagonize the output of cytokinin which regulates the development of embryo meristem. The genes related to abscisic acid negatively regulating the synthesis of gibberellin were strongly up-regulated in the mid-late stage of embryonic development. The results were reported the early synthesis and mid-late degradation of sucrose, as well as the activation of the continuous degradation pathway of temporary starch, providing the nutrients needed for differentiation of the embryonic cell. Moreover, the transcripts of genes involved in fatty acid synthesis were also abundantly accumulated in the zygotic embryos. CONCLUSION: Taken together, our research provides a new perspective on the developmental and metabolic regulation of zygotic embryo development at the transcriptional level in oil palm.

Assessing assemblage-wide mammal responses to different types of habitat modification in Amazonian forests.

Tropical forests are being heavily modified by varying intensities of land use ranging from structural degradation to complete conversion. While ecological responses of vertebrate assemblages to habitat modification are variable, such understanding is critical to appropriate conservation planning of anthropogenic landscapes. We assessed the responses of medium/large-bodied mammal assemblages to the ecological impacts of reduced impact logging, secondary regrowth, and eucalyptus and oil palm plantations in Eastern Brazilian Amazonia. We used within-landscape paired baseline-treatment comparisons to examine the impact of different types of habitat modification in relation to adjacent primary forest. We examined assemblage-wide metrics including the total number of species, number of primary forest species retained in modified habitats, abundance, species composition, and community integrity. We ranked all types of habitat modification along a gradient of assemblage-wide impact intensity, with oil palm and eucalyptus plantations exerting the greatest impact, followed by secondary regrowth, and selectively logging. Selectively-logged and secondary forests did not experience discernible biodiversity loss, except for the total number of primary forest species retained. Secondary forests further experienced pronounced species turnover, with loss of community integrity. Considering the biodiversity retention capacity of anthropogenic habitats, this study reinforces the landscape-scale importance of setting aside large preserved areas.

Ten years from propagule to mature plant of Butia purpurascens Glassman (Arecaceae): an endemic and endangered palm of the Brazilian Cerrado / Dez anos entre o propágulo e a planta madura de Butia purpurascens Glassman (Arecaceae): uma palmeira endêmica e ameaçada de extinção do Cerrado brasileiro

With occurrence mainly in the southwest Goiás, Butia purpurascens has fruits and leaves widely extracted by the regional population. Coexists with exotic grasses, frequent burnings and cattle's grazing and trampling. Young individuals are rarely seen. We aim to provide information about propagules, seedling formation and the monitoring of saplings of B. purpurascens until adults in reproductive phase. Fruits were selected, measured and benefited after harvest. Of 6,000 fruits collected 3,112 were discarded for being perforated by Conotrachelus weevils. The experiment divided 2,600 fruits into 13 treatments, distributed in ripe and immature fruits, with and without pulp. In addition, we adopt mechanical and chemical break dormancy mechanisms, different storage periods and seeding depths. After sixteen months of monitoring, the formation of eleven seedlings was obtained without distinction of any treatment. Seedlings and saplings developed slowly, taking two years to emit the first metaphyll. Over time, ten individuals died, most from fungal attack. After ten years, the only surviving palm generated two inflorescences, which produced fruit. The inefficient seedling production and the slow development of saplings, combined with the impact of the extractivism and the high rate of predation of the pyrenes, suggest the low recruitment rate of the species observed, in natural conditions. This type of data is one of the important tools for creating guidelines for the species conservation. Therefore, we suggest considering the reclassification of B. purpurascens as a Critically Endangered species in the Official List of Threatened Brazilian Species of Extinction.

Com ocorrência concentrada no sudoeste goiano, Butia purpurascens tem frutos e folhas amplamente extraídos pela população regional. Coexiste com gramíneas exóticas, queimadas frequentes, além do pastejo e pisoteamento por gado. Os indivíduos jovens raramente são vistos. Este trabalho teve como objetivo fornecer informações sobre propágulos, formação de plântulas e monitoramento de indivíduos jovens de B. purpurascens até adultos em fase reprodutiva. Os frutos foram selecionados, medidos e beneficiados após a colheita. Dos 6.000 frutos coletados, 3.112 foram descartados por estarem perfurados por gorgulhos do gênero Conotrachelus. O experimento dividiu 2.600 frutos em 13 tratamentos, distribuídos em frutos maduros e imaturos, com polpa e despolpados. Além da adoção de mecanismos mecânicos e químicos de quebra de dormência, períodos de armazenamento e profundidades de plantio diferentes. Após 16 meses de monitoramento, a formação de 11 plântulas foi obtida sem distinção de qualquer tratamento. Plântulas e indivíduos jovens se desenvolveram lentamente, levando dois anos para emitir o primeiro metáfilo. Ao longo do tempo, dez indivíduos morreram, a maioria, por ataque fúngico. Após dez anos, a única planta sobrevivente gerou duas inflorescências, as quais produziram frutos. A capacidade de produção de plântulas ineficiente e o lento desenvolvimento das mudas, combinados com o impacto do extrativismo e a alta taxa de predação dos pirênios, sugerem a baixa taxa de recrutamento da espécie observada, em condições naturais. Esse tipo de dado é uma das ferramentas importantes para a criação de diretrizes para a conservação de espécies. Portanto, sugerimos considerar a reclassificação de B. purpurascens como espécie Criticamente Ameaçada na Lista Nacional Oficial de Espécies da Flora Brasileira Ameaçadas de Extinção.

The critical role of natural forest as refugium for generalist species in oil palm-dominated landscapes.

In Borneo, oil palm plantations have replaced much of natural resources, where generalist species tend to be the principal beneficiaries, due to the abundant food provided by oil palm plantations. Here, we analyse the distribution of the Asian water monitor lizard (Varanus salvator) population within an oil palm-dominated landscape in the Kinabatangan floodplain, Malaysian Borneo. By using mark-recapture methods we estimated its population size, survival, and growth in forest and plantation habitats. We compared body measurements (i.e. body weight and body length) of individuals living in forest and oil palm habitats as proxy for the population's health status, and used general least squares estimation models to evaluate its response to highly fragmented landscapes in the absence of intensive hunting pressures. Contrary to previous studies, the abundance of lizards was higher in the forest than in oil palm plantations. Recruitment rates were also higher in the forest, suggesting that these areas may function as a source of new individuals into the landscape. While there were no morphometric differences among plantation sites, we found significant differences among forested areas, where larger lizards were found inhabiting forest adjacent to oil palm plantations. Although abundant in food resources, the limited availability of refugia in oil palm plantations may intensify intra-specific encounters and competition, altering the body size distribution in plantation populations, contrary to what happens in the forest. We conclude that large patches of forest, around and within oil palm plantations, are essential for the dynamics of the monitor lizard population in the Kinabatangan floodplain, as well as a potential source of individuals to the landscape. We recommend assessing this effect in other generalist species, as well as the impact on the prey communities, especially to reinforce the establishment of buffer zones and corridors as a conservation strategy within plantations.

Phenology of the endangered palm Ceroxylon quindiuense (Arecaceae) along an altitudinal gradient in Colombia / Fenología de la palma en peligro Ceroxylon quindiuense (Arecaceae) a lo largo de un gradiente altitudinal en Colombia

Abstract Introduction: Understanding the phenology of plant populations is vital for their conservation and management. We studied the vegetative and reproductive phenology of the endangered palm Ceroxylon quindiuense along an altitudinal gradient in the Central Cordillera of Colombia. Objective: We describe the leaf production rate, and flowering and fruiting cycles, and calculate food offer for the fauna, as a tool for the proper management of the palm. Methods: At each sampling site (2 400, 2 600, 2 800, 3 000 m.a.s.l.), we marked 40 adult individuals (20 pistillate, 20 staminate), which we followed bimonthly for 24 months. We studied leaf production by counting fallen leaves. We followed flower and fruit production through observations with binoculars and photographs. Results: Each adult individual produced, on average, one leaf every 69 days. Although isolated individuals flowered throughout the year, most palms flowered synchronously at each elevation in October 2016-August 2017 and in August 2018-February 2019 and had ripe fruits 7-13 months later. Flowering started at 2 600 m, followed by 2 800 and 3 000 m. Palms at 2 400 m, the lower limit of the palm stands in the area, showed a singular behavior, with scarce flower and fruit production, some individuals that changed sex, and a higher proportion of pistillate palms. Each palm produced 1-11 (x̄ = 5.3, SD = 2.2) inflorescences and 1-10 (x̄ = 5.3, SD = 2.2) infructescences. The average number of fruits per infructescence was 4 465 (SD = 1 488). With an estimated population of adult palms between 256 000 and 600 000 and an overall ratio of pistillate: staminate individuals 1:1 or 1:2, total fruit production in the area during each fruiting period is estimated as 2.0-7.1 billion fruits. Conclusions: The huge number of flowers and fruits and their gradual availability along the altitudinal gradient have a major impact on the spatial and temporal distribution of food offer for fauna associated with the palm.

Resumen Introducción: Comprender la fenología de las poblaciones de plantas es vital para su conservación y manejo. Estudiamos la fenología vegetativa y reproductiva de la palma amenazada Ceroxylon quindiuense a lo largo de un gradiente altitudinal en la Cordillera Central de Colombia. Objetivo: Describimos la tasa de producción de hojas, los ciclos de floración y fructificación, y calculamos la oferta alimentaria para la fauna, como una herramienta para el adecuado manejo de la palma. Métodos: En cada sitio de muestreo (2 400, 2 600, 2 800, 3 000 m.s.n.m.), marcamos 40 individuos adultos (20 pistilados, 20 estaminados), que seguimos bimestralmente durante 24 meses. Estudiamos la producción de hojas contando las caídas al suelo. Seguimos la producción de flores y frutos a través de observaciones con binoculares y fotografías. Resultados: Cada individuo adulto produjo, en promedio, una hoja cada 69 días. Aunque los individuos aislados florecieron durante todo el año, la mayoría de las palmas florecieron sincrónicamente en cada elevación entre octubre 2016 y agosto 2017 y de agosto 2018 a febrero 2019 y tuvieron frutos maduros entre 7-13 meses después. La floración comenzó a los 2 600 m, seguida de los 2 800 y los 3 000 m. Las palmas a 2 400 m, límite inferior de los palmares de la zona, mostraron un comportamiento singular, con escasa producción de flores y frutos, varios individuos que cambiaron de sexo y una mayor proporción de palmas pistiladas. Cada palma produjo 1-11 (x̄ = 5.3, SD = 2.2) inflorescencias y 1-10 (x̄ = 5.3, SD = 2.2) infrutescencias. El número promedio de frutos por infrutescencia fue de 4 465. Con una población estimada de palmas adultas entre 256 000 y 600 000 y una proporción total de individuos pistilados: estaminados 1:1 o 1:2, la producción total de frutos en el área durante cada período de fructificación se estima en 2.0-7.1 mil millones de frutos. Conclusiones: La gran cantidad de flores y frutos y su progresiva disponibilidad a lo largo del gradiente tienen un impacto importante en la distribución espacial y temporal de la oferta de alimento para la fauna asociada a la palma.

Restoration of gallery forest patches improves recruitment of motacú palms (Attalea princeps) while diversifying and increasing wildlife populations.

Globally, forest-savanna mosaic landscapes are of significant conservation importance but have been widely impacted by human land-use. We studied how restoration, through cessation of long-term cattle grazing impacts (i) forest regeneration; (ii) forest understory structure and composition; and (iii) populations and diversity of large mammals and nocturnal birds, within naturally patchy gallery forests in the Beni Savannas of Bolivia. Comparing grazed and restored sites, we assessed the abundance and composition of tree functional types at different life stages (seedlings, saplings and adults), with focus on the region's key palm species Attalea princeps (motacú). Additionally, we surveyed habitat structure and composition in the shrub and ground-layer, and monitored occurrence and encounter rates of large mammals and nocturnal birds along dusk and evening transects. We found evidence of lower recruitment of motacú palms on the grazed site and lower potential for natural motacú regeneration. Principal Components Analysis revealed forests on grazed sites had simpler, more open shrub-layers and altered ground-layer structure and composition including increased bare ground. Mammal species richness was greater on the restored site, and there were more declining, globally threatened and site-unique species. Species richness was similar for nocturnal birds within forests on both the grazed and restored site, but nearly all species tended to be encountered more frequently on the restored site. Our results suggest cattle negatively impact forest regeneration and alter the structure and composition of the shrub and ground layer with potential consequences for the diversity and abundance of wildlife. Our study represents one of only a handful completed in the Beni region of Bolivia to date. The Beni is currently under pressure from widespread, largely unregulated cattle ranching. Our results thus provide vital evidence to support development of restoration and conservation policy, and its integration with rangeland management in this threatened and critically understudied region.

Diversity and Abundance of Predatory Arthropods on Immature and Mature Oil Palm (Elaeis guineensis) Plantations.

BACKGROUND AND OBJECTIVE: Predatory arthropods may play a crucial role in decreasing the pest population that causes a significant loss in oil palm production. In this study, we investigated the diversity of predatory arthropods and their abundance on immature and mature oil palm plantation grown in Aceh Tamiang, Sumatra, Indonesia. MATERIALS AND METHODS: Arthropod predators were collected by using light trap, yellow-pan trap and pitfall trap that were placed on an immature and mature oil palm plantation. Specimens were sorted and identified in the Laboratory. RESULTS: The results showed that there were 674 individuals arthropod predators (insects and spiders) consisted of 7 orders, 22 families and 37 morphospecies collected in the immature plantation. While in mature plantation, arthropod predators found were 740 individuals consisted of 6 orders 23 families and 42 morphospecies. Ants (Hymenoptera: Formicidae) dominated other families regarding morphospecies and individual numbers. There was no significant difference in term of species richness and abundance of predators between both phases of the plantation which implied that the two plantations hosted a similar composition and abundance of predators. The diversity indices of predators calculated in both plantations showed that the predators were categorized as middle level of diversity and middle level of individual distribution, However, the community is unstable. CONCLUSION: Our results suggested that predatory predators were present in similar structure in both phases of oil palm plantations. Efforts to conserve them are needed to enhance their performance as part of a sustainable and environmentally friendly method for controlling pests in oil palm plantation.

Genome-wide association study (GWAS) of major QTLs for bunch and oil yield related traits in Elaeis guineensis L.

Oil palm (Elaeis guineensis Jacq.) is a long breeding cycle perennial crop with a genome size of 1.8 Gb. This is the first report of GWAS on large number of 310 African germplasm using 400 SSR markers till date. Highly significant correlation was found between leaf area (LA) and rachis length (RL) (0.75) followed by bunch weight (BW) and bunch index (BI) (0.65), whereas negative correlation was observed between bunch number (BN) and average bunch weight (ABW). First two principal component analysis (PCA) together explained maximum amount of variation (84.5 %). The PCA1 revealed that group 2 (Guinea Bissau and Cameroon) and group 4 (Zambia and Cameroon) genotypes are best suitable for BN, BI and BW traits. GWAS of six bunch yield and seven bunch oil yield traits with SSRs resulted in the identification 43 significant quantitative trait loci (QTLs) by mixed linear model (MLM) approach. Seven SSR loci were found to be linked to oil to dry mesocarp (ODM) on chromosomes 1,4,7,10,12 and 15. The SSR locus mEgCIR1753 for ODM was significantly linked at a p of ≤0.05 which explained 34.6 % of phenotypic variance. The important parameters like ODM, OWM and OB were located on 4, 10, 11 and 15 chromosomes. The leaf area and ODM were associated with candidate genes representing of low-temperature-induced 65 kDa proteins. The identified markers can be effectively used for marker assisted selection of high yielding oil palm genotypes.

Modal properties of fruit-rachilla system of the macaw palm.

The macaw palm has been domesticated due to its potential use in the production of biofuel, in addition to several co-products that can be generated from its oil and pulp. One of the current challenges in this area is the harvesting, as there are no specific machines for this operation. Therefore, it is necessary to determine the appropriate information regarding the physical properties of the plant, so that it is feasible to develop the technologies necessary for the commercial scale application of macaw palm, allowing it to contribute to the sustainable production of raw material for the biofuel industry and other co-products. The principle of mechanical vibration can be used to shed fruit from trees when ripe, and it can be a method used for harvesting. Thus, as proposed in this study, it was necessary to study the dynamic behavior of the fruit-rachilla system during vibration. Hence, the modal properties of the system were determined. A study on the dynamic behaviors was carried out using a deterministic finite element model, and the natural frequencies were obtained through a frequency-scanning test to evaluate the model. The mean relative error (MRE) between the measured and simulated natural frequencies was also used to evaluate the model. The natural frequencies, determined experimentally, varied from 26.21 to 33.45 Hz on average, whereas the simulated frequencies varied from 24.81 to 39.27 Hz. The overall MRE was 9.08%. Once the model was validated, a sensibility test was carried out, which showed that the density of fruit and the elasticity modulus are the parameters that most influence the natural frequencies of the fruit-rachilla system.

The environmental impacts of palm oil in context.

Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15). The production of vegetable oils and, in particular, palm oil, illustrates these competing demands and trade-offs. Palm oil accounts for ~40% of the current global annual demand for vegetable oil as food, animal feed and fuel (210 Mt), but planted oil palm covers less than 5-5.5% of the total global oil crop area (approximately 425 Mha) due to oil palm's relatively high yields. Recent oil palm expansion in forested regions of Borneo, Sumatra and the Malay Peninsula, where >90% of global palm oil is produced, has led to substantial concern around oil palm's role in deforestation. Oil palm expansion's direct contribution to regional tropical deforestation varies widely, ranging from an estimated 3% in West Africa to 50% in Malaysian Borneo. Oil palm is also implicated in peatland draining and burning in Southeast Asia. Documented negative environmental impacts from such expansion include biodiversity declines, greenhouse gas emissions and air pollution. However, oil palm generally produces more oil per area than other oil crops, is often economically viable in sites unsuitable for most other crops and generates considerable wealth for at least some actors. Global demand for vegetable oils is projected to increase by 46% by 2050. Meeting this demand through additional expansion of oil palm versus other vegetable oil crops will lead to substantial differential effects on biodiversity, food security, climate change, land degradation and livelihoods. Our Review highlights that although substantial gaps remain in our understanding of the relationship between the environmental, socio-cultural and economic impacts of oil palm, and the scope, stringency and effectiveness of initiatives to address these, there has been little research into the impacts and trade-offs of other vegetable oil crops. Greater research attention needs to be given to investigating the impacts of palm oil production compared to alternatives for the trade-offs to be assessed at a global scale.

Energetic neutral atoms assisted development of kithul (Caryota urens) starch-lauric acid complexes: A characterisation study.

Kithul starch was treated by EN (energetic neutral nitrogen) atoms at 6 W,12 W and 18 W for 15 min and incorporated lauric acid for the development of starch-lauric acid inclusion complexes. EN atoms treatment significantly (p ≤ 0.05) increased the complex index (CI). Severe morphological alterations on the kithul starch granules by EN atoms treatment enhanced starch-lauric acid complex formation. Relative crystallinity of EN atoms treated lauric acid incorporated kithul starch samples increased with plasma power. Moreover, lower pasting property, storage modulus (G'), loss modulus (G''), hardness and higher Tanδ indicated decrease in gelation and retrogradation property. ENL-18 W showed the lowest complex viscosity (È *). Lauric acid incorporation in EN atoms treated kithul starch reduced in vitro digestibility and significantly (p ≤ 0.05) increased RS (resistant starch). Hence, EN atoms treatment on the kithul starch granules prior to fatty acid incorporation is an effective technique for the development of starch-fatty acid complexes.

Phenazine from Pseudomonas aeruginosa UPMP3 induced the host resistance in oil palm (Elaeis guineensis Jacq.)-Ganoderma boninense pathosystem.

Pseudomonas aeruginosa developed its biocontrol agent property through the production of antifungal derivatives, with the phenazine among them. In this study, the applications of crude phenazine synthesized by Pseudomonas aeruginosa UPMP3 and hexaconazole were comparatively evaluated for their effectiveness to suppress basal stem rot infection in artificially G. boninense-challenged oil palm seedlings. A glasshouse experiment under the randomized completely block design was set with the following treatments: non-inoculated seedlings, G. boninense inoculated seedlings, G. boninense inoculated seedlings with 1 mg/ml phenazine application, G. boninense inoculated seedlings with 2 mg/ml phenazine application and G. boninense inoculated seedlings with 0.048 mg/ml hexaconazole application. Seedlings were screened for disease parameters and plant vigour traits (plant height, plant fresh weight, root fresh, and dry weight, stem diameter, and total chlorophyll) at 1-to-4 month post-inoculation (mpi). The application of 2 mg/ml phenazine significantly reduced disease severity (DS) at 44% in comparison to fungicide application (DS = 67%). Plant vigour improved from 1 to 4 mpi and the rate of disease reduction in seedlings with phenazine application (2 mg/ml) was twofold greater than hexaconazole. At 4, 6 and 8 wpi, an up-regulation of chitinase and ß-1,3 glucanase genes in seedlings treated with phenazine suggests the involvement of induced resistance in G. boninense-oil palm pathosystem.

Mass sterilization of a common palm species by elephants in Kruger National Park, South Africa.

Chronic herbivory by elephants rarely eliminates any species of woody savanna plants because these plants are typically vigorous basal resprouters after damage by fire or herbivory. In some instances, resprouting after elephant herbivory even increases stem numbers per unit area compared to protected areas. It is thus difficult to know whether an area has been severely degraded by elephant herbivory or not because although trees may be severely reduced in size, they will still be present and may even be relatively dense. By using an elephant exclosure in the Kruger National Park, South Africa, we demonstrate that this resprouting ability masks the fact that entire populations of a widespread African palm, Hyphaene petersiana, are prevented from reaching sexual maturity by chronic elephant herbivory. Besides sterilizing these palms and thus preventing their evolution and seed dispersal, the absence of the palm fruits, flowers and tall stems has other negative biodiversity impacts on their associated fauna. We suggest that to determine sustainable elephant impacts on savanna plants, conservation managers also use the reproductive condition of savanna plants rather than their presence, height or stem density.

Major QTLs for Trunk Height and Correlated Agronomic Traits Provide Insights into Multiple Trait Integration in Oil Palm Breeding.

Superior oil yield is always the top priority of the oil palm industry. Short trunk height (THT) and compactness traits have become increasingly important to improve harvesting efficiency since the industry started to suffer yield losses due to labor shortages. Breeding populations with low THT and short frond length (FL) are actually available, such as Dumpy AVROS pisifera (DAV) and Gunung Melayu dura (GM). However, multiple trait stacking still remains a challenge for oil palm breeding, which usually requires 12-20 years to complete a breeding cycle. In this study, yield and height increment in the GM × GM (GM-3341) and the GM × DAV (GM-DAV-3461) crossing programs were evaluated and palms with good yield and smaller height increment were identified. In the GM-3341 family, non-linear THT growth between THT_2008 (seven years old) and THT_2014 (13 years old) was revealed by a moderate correlation, suggesting that inter-palm competition becomes increasingly important. In total, 19 quantitative trait loci (QTLs) for THT_2008 (8), oil per palm (O/P) (7) and FL (4) were localized on the GM-3341 linkage map, with an average mapping interval of 2.01 cM. Three major QTLs for THT_2008, O/P and FL are co-located on chromosome 11 and reflect the correlation of THT_2008 with O/P and FL. Multiple trait selection for high O/P and low THT (based on the cumulative effects of positive alleles per trait) identified one palm from 100 palms, but with a large starting population of 1000-1500 seedling per cross, this low frequency could be easily compensated for during breeding selection.

Residue and Dissipation Kinetics of Metsulfuron-Methyl Herbicide in Soil: A Field Assessment at an Oil Palm Plantation.

A field trial experiment was conducted to investigate the degradation of metsulfuron-methyl at two application dosages, 15 g a.i/ha and 30 g a.i/ha, at an oil palm plantation. Soil samples were collected at ‒1, 0, 1, 3, 7, 14, and 21 days after treatment (DAT) at the following depths: 0-10, 10-20, 20-30, 30-40, and 40-50 cm. The results showed rapid degradation of metsulfuron-methyl in the soil, with calculated half-life (t½) values ranging from 6.3 and 7.9 days. The rates of degradation of metsulfuron-methyl followed first-order reaction kinetics (R2 = 0.91-0.92). At the spray dosage of 15 g a.i/ha, metsulfuron-methyl residue was detected at up to 20-30 cm soil depth, at 3.56% to 1.78% at 3 and 7 DAT, respectively. Doubling the dosage to 30 g a.i/ha increased the metsulfuron-methyl residue in up to 30-40 cm soil depth at 3, 7, and 14 DAT, with concentrations ranging from 1.90% to 1.74%. These findings suggest that metsulfuron-methyl has a low impact on the accumulation of the residues in the soil at application dosages of 15 g a.i/ha and 30 g a.i/ha, due to rapid degradation, and the half-life was found to be 6.3 to 7.9 days.

Identification and characterisation of thiamine pyrophosphate (TPP) riboswitch in Elaeis guineensis.

The oil palm (Elaeis guineensis) is an important crop in Malaysia but its productivity is hampered by various biotic and abiotic stresses. Recent studies suggest the importance of signalling molecules in plants in coping against stresses, which includes thiamine (vitamin B1). Thiamine is an essential microelement that is synthesized de novo by plants and microorganisms. The active form of thiamine, thiamine pyrophosphate (TPP), plays a prominent role in metabolic activities particularly as an enzymatic cofactor. Recently, thiamine biosynthesis pathways in oil palm have been characterised but the search of novel regulatory element known as riboswitch is yet to be done. Previous studies showed that thiamine biosynthesis pathway is regulated by an RNA element known as riboswitch. Riboswitch binds a small molecule, resulting in a change in production of the proteins encoded by the mRNA. TPP binds specifically to TPP riboswitch to regulate thiamine biosynthesis through a variety of mechanisms found in archaea, bacteria and eukaryotes. This study was carried out to hunt for TPP riboswitch in oil palm thiamine biosynthesis gene. Riboswitch detection software like RiboSW, RibEx, Riboswitch Scanner and Denison Riboswitch Detector were utilised in order to locate putative TPP riboswitch in oil palm ThiC gene sequence that encodes for the first enzyme in the pyrimidine branch of the pathway. The analysis revealed a 192 bp putative TPP riboswitch located at the 3' untranslated region (UTR) of the mRNA. Further comparative gene analysis showed that the 92-nucleotide aptamer region, where the metabolite binds was conserved inter-species. The secondary structure analysis was also carried out using Mfold Web server and it showed a stem-loop structure manifested with stems (P1-P5) with minimum free energy of -12.26 kcal/mol. Besides that, the interaction of riboswitch and its ligand was determined using isothermal titration calorimetry (ITC) and it yielded an exothermic reaction with 1:1 stoichiometry interaction with binding affinities of 0.178 nM, at 30°C. To further evaluate the ability of riboswitch to control the pathway, exogenous thiamine was applied to four months old of oil palm seedlings and sampling of spear leaves tissue was carried out at days 0, 1, 2 and 3 post-treatment for expression analysis of ThiC gene fragment via quantitative polymerase chain reaction (qPCR). Results showed an approximately 5-fold decrease in ThiC gene expression upon application of exogenous thiamine. Quantification of thiamine and its derivatives was carried out via HPLC and the results showed that it was correlated to the down regulation of ThiC gene expression. The application of exogenous thiamine to oil palm affected ThiC gene expression, which supported the prediction of the presence of TPP riboswitch in the gene. Overall, this study provides the first evidence on the presence, binding and the functionality of TPP riboswitch in oil palm. This study is hoped to pave a way for better understanding on the regulation of thiamine biosynthesis pathway in oil palm, which can later be exploited for various purposes especially in manipulation of thiamine biosynthesis pathways in combating stresses in oil palm.

Seed Germination in Oil Palm (Elaeis guineensis Jacq.): A Review of Metabolic Pathways and Control Mechanisms.

Oil palm is an oil-producing crop of major importance at the global scale. Oil palm mesocarp lipids are used for myriads industrial applications, and market demand has been growing for decades. In addition, oil palm seeds are oleaginous, and the oil extracted therefrom can be used for several purposes, from food to cosmetics. As such, there is a huge need in oil palm seeds to maintain the global cohort of more than 2 billion trees. However, oil palm seed germination is a rather difficult process, not only to break dormancy, but also because it is long and often reaches lower-than-expected germination rates. Surprisingly, despite the crucial importance of germination for oil palm plantation management, our knowledge is still rather limited, in particular about germinating oil palm seed metabolism. The present review incorporates different pieces of information that have been obtained in the past few years, in oil palm and in other palm species, in order to provide an overview of germination metabolism and its control. Further insights can also be gained from other oleaginous model plants, such as Arabidopsis or canola, however, palm seeds have peculiarities that must be accounted for, to gain a better understanding of germinating seed metabolism.