Palm Species Research Articles

Amino acids, fatty acids and mineral elements composition of Roystonea regia and Ptychosperma macarthurii palm kernels

Roystonea regia and Ptychosperma macarthurii are exotic palm species widely grown in Nigeria as ornamentals. The kernels of R. regia and P. macarthurii were subjected to amino acids, fatty acids, and mineral elements analyses in this study. Glutamic acid (13. 64 and 14.00 g/100 g), aspartic acid (9.72 and 9.50 g/100 g), arginine (8.68 and 7.49 g/100 g), and leucine (7.23 and 7.98 g/100 g) were the dominant amino acids in R. regia and P. macarthurii seeds. The percentage yields of kernel oils were 13.9 and 1.7% for R. regia and P. macarthurii, respectively. Gas chromatograph facilitated the identification of thirteen fatty acids, mainly comprised of oleic acid (25.19 and 35.64%), linoleic acid (57.88 and 45.60%), and palmitic acid (9.6 and 10.03%) in R. regia and P. macarthurii, respectively. The analysis also revealed the high unsaturated nature of fixed oils of R. regia (83.63%) and P. macarthurii kernels (81.66%). Calcuim, copper, iron, zinc, magnesium, manganese, sodium, and potassium were also detected in the kernels; majorly, calcium (71.5 mg/L) and magnesium (23.1 mg/L) in P. macarthurii kernels, whereas sodium (24.6 ppm) and potassium levels (50.1 ppm) were higher in R. regia kernels. These results reveal the high amino acids, fatty acids, and mineral elements content of R. regia and P. macarthurii kernels. These unexploited palm fruits could be properly utilized as animal feed, edible oil, or for other industrial purposes with the knowledge of its nutritional value and fixed oil content.

Landscape heterogeneity drives spatial distribution of palm community in a Neotropical rainforest reserve affected by defaunation

Background: Our study presents the first assessment of the relationships between environmental heterogeneity and the palm community at the landscape scale at the northern boundary of tropical rainforest distribution in America.
 Question: How does landscape-level heterogeneity (edaphic, topographic as well as the density, diversity, and tree biomass) shapes the palm community in a protected reserve affected by defaunation?
 Study site and date: The study was carried out in Los Tuxtlas Tropical Biology Station, Veracruz, Mexico (2020).
 Methods: We delineated landscape units (LUs) based on soil and geomorphology to characterize the biophysical mosaic. We built rank-abundance curves to compare the palm richness and their abundance among LUs. Permutational multivariate analysis of variance (PERMANOVA) and nonmetric multidimensional scaling (NMDS) were applied to detect shifts in the palm community across LUs.
 Results: Integrating abiotic and biotic components by delimiting LUs allowed us to evaluate the multifactorial effect of environmental heterogeneity on the palm community. The density and composition of the palms changed significantly among the LUs, influenced by soil coarse fragments, elevation, slope inclination, and annual precipitation. Tree richness and density had a significant effect on the palm community only when analyzed in combination with the soil-topography variables.
 Conclusions: The results reveal that there is high edaphic and topographic heterogeneity that influences palm species distribution at the landscape scale. The environmental heterogeneity approach allows capturing novel abiotic variation to explain the distribution patterns of palm species and their coexistence in highly diverse tropical communities.

A Review on Digestive System of Rhynchophorus ferrugineus as Potential Target to Develop Control Strategies

Rhynchophorus ferrugineus, commonly known as red palm weevil (RPW), is a high-risk insect pest that has become a threat to many important palm species. There are several dominant factors that lead to the successful infestation of RPW, including its stealthy lifestyle, highly chitinized mouthpart, and high fecundity rate. Due to that, millions of dollars of losses have been suffered by many countries invaded by RPW. Several methods have been designed to control its invasion, including the usage of insecticides, but many cause resistance and environmental pollution. Therefore, an environmentally friendly insecticide that targets specific systems or pathways in RPW is urgently needed. One of the potential targets is the digestive system of RPW, as it is the major interface between the insect and its plant host. The related knowledge of RPW’s digestive system, such as the anatomy, microflora, transcriptomic analysis, and proteomic analysis, is important to understand its effects on RPW’s survival. Several data from different omics regarding the digestive systems of RPW have been published in separate reports. Some of the potential targets have been reported to be inhibited by certain potential insecticides, while other targets have not yet been tested with any inhibitors. Hence, this review may lead to a better understanding on managing infestations of RPW using the system biology approach for its digestive system.

Impact of Native Date Palm (Phoenix sylvestris) Based Agroforestry Practice for Livelihood Improvement and Biodiversity Conservation: Insights from South-Western Zone of Bangladesh

This study aims to explore the impacts of native date palm (Phoenix sylvestris) based agroforestry practices on the livelihood status and biodiversity conservation practices in south-western zone of Bangladesh. To conduct this exploratory study, data were collected from 70 farmers of Chaugachha upazila (sub-district) under Jessore district of Bangladesh using a pre-tested structured questionnaire during the period of May to June 2022. Findings of the study revealed that a wide range of plant species were available in the study area. Among these plant species, palms comprised the highest proportion (42%) while native date palm (Phoenix sylvestris) is the most dominant (38%) among the palm species. It is evident that native date palm based agroforestry practice has significant contributions to improve the livelihood of rural farmers, as majority of the farmers (47%) had moderate status of livelihood improvement while 32% of the farmers had high status of livelihood improvement. Despite facing a variety of challenges, the farmers are willing to continue this agroforestry practice in order to receive benefits from a wide range of aspects (human, social, natural, physical and financial). Most of the farmers of the study area depends on traditional knowledge and practices to manage their agroforestry system. So, proper initiatives need to be taken by the policy makers with provision to participatory training on improved agroforestry management practices and input support services (e.g. planting material, fertilizer, irrigation facility, farm equipment etc.). Priority should be given to ensure easy access to marketing and value chain system for the farmers to make this agroforestry practice economically profitable and a viable option for the rural farmers. This will also lead to develop a sustainable biodiversity management system in Bangladesh.

Identification of Green-Leaf Volatiles Released from Cabbage Palms (Sabal palmetto) Infected with the Lethal Bronzing Phytoplasma.

Lethal bronzing (LB) is a fatal infection that affects over 20 species of palms (Arecaceae) and is caused by the phytoplasma 'Candidatus Phytoplasma aculeata'. This pathogen causes significant economic losses to landscape and nursery companies in Florida, USA. Recently, the vector was determined to be the planthopper Haplaxius crudus, which was more abundant on LB-infected palms. Herein, the volatile chemicals emitted from LB-infected palms were characterized using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS). Infected Sabal palmetto were identified and confirmed as positive for LB via quantitative PCR. Healthy controls of each species were selected for comparison. All infected palms exhibited elevated levels of hexanal and E-2-hexenal. Threatened palms showed high releasing concentrations of 3-hexenal and Z-3-hexen-1-ol. The volatiles characterized herein are common green-leaf volatiles (GLVs) emitted by plants under stress. This study considers the first documented case of GLVs in palms attributed to phytoplasma infection. Due to the apparent attraction of LB-infected palms to the vector, one or several of the GLVs identified in this study could serve as a lure for the vector and supplement management programs.

Bioefficacy of an Oil-Emulsion Formulation of Entomopathogenic Fungus, Metarhizium anisopliae against Adult Red Palm Weevil, Rhynchophorus ferrugineus.

The red palm weevil (RPW), Rhynchophorus ferrugineus, poses a severe threat to agro-industrial crops, particularly major cultivated palm species. Infestations result in economic losses due to reduced fruit quality and yield. The entomopathogenic fungus, Metarhizium anisopliae, has shown promise as a potential biocontrol agent against the RPW. However, the use of an emulsion formulation of M. anisopliae for managing this serious insect pest has yet to be fully explored. The oil-emulsion formulation containing this entomopathogen may enhance the conidia's stability, prolong its lifetime, and reduce the impact of heat stress or UV irradiation on the fungus. Therefore, this study aimed to investigate the bioefficacy of a new oil-in-glycerol emulsion formulation on mycoinsecticidal activity against RPW adults by direct and indirect bioassays. Results showed that conidia concentration was directly proportional to the RPW mortality percentage. The LT50 of 8.183 days was achieved by the conidial formulation against RPW, with a significantly lower LC50 (1.910 × 105 conidia mL-1) compared to the aqueous conidia suspension (LT50 = 8.716 days; LC50 = 7.671 × 105 conidia mL-1). Indirect bioassays revealed that the oil-in-glycerol emulsion had a disease-spreading ability that resulted in up to 56.67% RPW mortality. A zero E-value reading indicates that the DNA sequence being studied is highly similar to that of the fungal species M. anisopliae, which has been identified in the NCBI database. Although the new emulsion formulation has improved the efficacy and pathogenicity of M. anisopliae in vitro, it is important to also consider the fungal pathogen's compatibility with other agricultural practices to prevent any loss of control efficiency in the actual usage environment.

First report of 'Candidatus Phytoplasma palmae' (16SrIV-A subgroup) associated with palm Lethal Yellowing disease on Cocos nucifera and Pritchardia sp. in Guadeloupe, French West Indies.

Lethal Yellowing (LY) disease causes major damage to palms in Central America and the Caribbean. It has been reported as far south as Antigua (Myrie et al., 2014). LY affects over forty palm species, seriously impacts the coconut industry and alters the landscapes on islands with a tourist-based economy. In March 2021, the presence of LY disease was regularly monitored in Guadeloupe. Two palm species (Cocos nucifera and Pritchardia sp.) died on a private property in Saint-Anne, Grande Terre. Yellowing of lower fronds and necrosis of inflorescences were reported on some neighboring palms. One symptomatic Cocos nucifera (GP21-007) and four symptomatic Pritchardia sp. (GP21-005, GP21-006, GP21-008 and GP21-009) were sampled by stem drilling. Samples from four asymptomatic coconut trees (GP21-001 to GP21-004) were collected in the locality of Deshaies. DNA was extracted from the nine sawdust samples following a cetyltrimethylammonium bromide (CTAB) modified protocol (Doyle and Doyle, 1990). A quantitative polymerase chain reaction (PCR), following the protocol described by Christensen et al. (2004), was performed on DNA to diagnose the presence of phytoplasmas. An exponential amplification was observed for all DNA extracts from symptomatic palm samples (threshold number of PCR cycles (Ct) ranged from 18.50 to 23.58). DNA from asymptomatic samples yielded negative results (undetermined Ct). To identify the phytoplasma associated with LY, DNA samples were subjected to PCR, based on the 16SrRNA gene, plus internal transcribed spacers (ITS) using P1-1T (Pilet et al., 2021)/P7 (Schneider et al., 1995) primers, and secA gene using the primer pair secAFor1/secARev1 (Hodgetts et al. 2008). Amplicons of 1.8 kb covering the 16S ribosomal operon and 830 bp for the secA gene were produced using DNA from symptomatic trees. All amplicons were double strand sequenced (Genewiz, UK). The corresponding sequences were deposited in GenBank and subjected to BLASTn on NCBI. Sequences of the ribosomal operon gene (accession no. ON521114 to ON521118) were identical for the five positive samples. Sequencing revealed two distinct ribosomal operons with heterozygous peaks on the DNA chromatogram. The first aMino ambiguity (M = Adenine or Cytosine) was observed in the 16Sr RNA gene. The second was observed in the first intergenic transcript spacer. The 16S rDNA sequence (M = Cytosine) presented 100% identity with accession no. HQ613874 and 99.93% with accession no. U18747, the reference sequence for 'Candidatus Phytoplasma palmae'. The virtual RFLP pattern derived from the 16S rDNA F2nR2 fragment and identified using iPhyclassifier (Zhao et al. 2009) was identical to the reference pattern for the 16SrIV-A subgroup. A unique sequence was obtained for the partial secA gene (OP136139 to OP136143), sharing 100% identity with EU267187 for the palm LY phytoplasma preprotein translocase subunit (secA) gene. This is the first report of 'Ca. Phytoplasma palmae' (subgroup 16SrIV-A) associated with palm LY disease on Cocos nucifera and Pritchardia sp. in Guadeloupe. Measures to eradicate LY were implemented as soon as its presence was confirmed in Guadeloupe. LY phytoplasmas continue to spread in the Caribbean and are approaching South America, where the known vector, Haplaxius crudus, has already been reported (Silva et al., 2019). This poses a major threat to the coconut economy and the diversity of palm trees.

The Critically Endangered Haitian endemic palm Attalea crassispatha (Arecaceae) and its living collections in Fairchild Tropical Botanic Garden: Perspectives from conservation surveys and DNA microsatellite (SSR) data

With only 24 plants located in the wild in 2017, the Haitian endemic Attalea crassispatha (Mart.) Burret (Arecaceae) is one of the major priorities for palm conservation in the Caribbean Island Biodiversity Hotspot and is the only member of the genus (~ 30 species) that occurs in the region. A project of ex situ conservation and field surveys published in 1994 involved Fairchild Tropical Botanic Garden (FTBG) as a major distributor of wild collected germplasm with other botanic gardens/institutions from South Florida and the tropics in 1989 and 1991. Part of this material was also grown in FTBG. Over 25 years after this conservation initiative was established, new field surveys were made in 2017 where the species occurs in Peninsule de Tiburon, southern Haiti. The number of living plants recorded in this new inventory was 24 (vs 25 reported in 1994). DNA microsatellite data (SSRs) were used to compare levels of genetic variation in the FTBG ex situ conservation collections and the wild. We found that the FTBG genotypes did not capture most of the already limited genetic diversity found in the wild. Cluster analyses based on Bayesian statistics recognized three major genetic groups in the wild, and three of them were found in plants occurring mostly in the northern slopes of Peninsule de Tiburon; in contrast, only two of the genetic clusters were predominant in the southern portion of this peninsula mostly in the Cavaillon area. Our results concur with those recently published based on Single-nucleotide polymorphisms (SNPs) molecular markers for ex situ collections of this palm species conserved in five botanic gardens/research institutes.

Saltwater intrusion ecophysiological effects on Pseudophoenix sargentii, Roystonea regia, Sabal palmetto “Lisa,” and Thrinax radiata in South Florida

Climate change will alter natural areas on a global scale within the next century, especially in low-lying coastal areas where sea-level rise is predicted to severely degrade or destroy many ecosystems. As sea-level rise continues, it is expected that salinity due to saltwater intrusion will impact soil health and agricultural production, this is of even greater importance in areas such as South Florida where the surface and groundwater resources are hydrologically connected due to the shallow and highly permeable limestone soils. The chlorophyll concentrations in leaf tissue were chosen as the primary health indicator to assess whether this is a valuable factor to consider for plant health risk assessment and whether optical sensor technology such as the SPAD and NDVI, are valuable tools when understanding the impact seawater encroachment has on plant nitrogen uptake. Therefore, the aim of this study was to evaluate the effects of salt concentrations on plant growth and health of four palm species. The treatments were from pure reverse osmosis water, Fresh water, brackish water, seawater and hypersaline water (0, 0.5, 5, 10, 15, 25, and 50 ppt). Control treatment that received reverse osmosis filtrated water with a salinity concentration of 0 ppt had the highest health-indicator averages compared to treatment 50 ppt. As the salinity increased, all health indicators gradually declined or remained rather constant and declined as they approached the greater salinity concentrations. The growth parameters and chlorophyll content were reduced over time, particularly at higher salt concentrations for all palm species studied. The chlorophyll content by SPAD and the normalized difference vegetation index (NDVI) can be used as health indicators of the palm species studied, as it was observed in this study a decline in the chlorophyll content as there was an increase in salt concentrations. It is important to emphasize that leaf chlorosis and subsequent decline of palm species were observed in the treatment with higher salt concentration, thus highlighting the importance of chlorophyll content as an indicator of plant health. The species Roystonea regia was very susceptible to salinity, and the palm Sabal palmetto is more susceptible to salinity than the Thrinax radiata and Pseudophoenix sargentii palms.

Factors Affecting Pollination and Pollinators in Oil Palm Plantations: A Review with an Emphasis on the Elaeidobius kamerunicus Weevil (Coleoptera: Curculionidae).

Pollination is crucial for oil palm yield, and its efficiency is influenced by multiple factors, including the effectiveness of Elaeidobius kamerunicus weevils as pollinators in Southeast Asia. Weevils transfer pollen between male and female flowers, leading to successful fertilization and fruit development, which contributes to higher oil palm yields and increased production of valuable oil. Understanding and conserving the weevil population is important for sustainable oil palm cultivation practices. The interaction between pollinators, including weevils, and environmental factors is complex, involving aspects such as pollinator behavior, abundance, diversity, and effectiveness, which are influenced by weather, landscape composition, and pesticide use. Understanding these interactions is critical for promoting sustainable pollination practices, including effective pest management and maintaining optimal pollinator populations. This review discusses various abiotic and biotic factors that affect pollination and pollinators in oil palm plantations, with a particular focus on weevils as primary pollinators. Factors such as rainfall, humidity, oil palm species, temperature, endogamy, parasitic nematodes, insecticides, predators, and proximity to natural forests can impact the weevil population. Further research is recommended to fill knowledge gaps and promote sustainable pollination practices in the oil palm industry.

Genomics and Transcriptomics Reveal Genetic Contribution to Population Diversity and Specific Traits in Coconut.

Coconut is an economically important palm species with a long history of human use. It has applications in various food, nutraceuticals, and cosmetic products, and there has been renewed interest in coconut in recent years due to its unique nutritional and medicinal properties. Unfortunately, the sustainable growth of the coconut industry has been hampered due to a shortage of good quality seedlings. Genetic improvement through the traditional breeding approach faced considerable obstacles due to its perennial nature, protracted juvenile period, and high heterozygosity. Molecular biotechnological tools, including molecular markers and next-generation sequencing (NGS), could expedite genetic improvement efforts in coconut. Researchers have employed various molecular markers to reveal genetic diversity among coconut populations and for the construction of a genetic map for exploitation in coconut breeding programs worldwide. Whole genome sequencing and transcriptomics on the different varieties have generated a massive amount of publicly accessible sequence data, substantially improving the ability to analyze and understand molecular mechanisms affecting crop performance. The production of high-yielding and disease-resilient coconuts and the deciphering of the complex coconut genome's structure can profit tremendously from these technologies. This paper aims to provide a comprehensive review of the progress of coconut research, using genomics, transcriptomics, and molecular markers initiatives.

Pest categorisation of coconut cadang-cadang viroid.

The EFSA Panel on Plant Health updated its 2017 pest categorisation of coconut cadang cadang viroid (CCCVd) for the EU territory due to new data on its host range. The identity of CCCVd, a member of the genus Cocadviroid (family Pospiviroidae), is established and detection and identification methods are available. It is included as a quarantine pest for the EU in the Commission Implementing Regulation (EU) 2019/2072. CCCVd has been reported from the Philippines and Malaysia. It is not known to be present in the EU. The host range of CCCVd is restricted to Arecaceae species (palms), in particular, coconut palm (Cocos nucifera) to which it causes a lethal disease. Oil palm (Elaeis guineensis) and buri palm (Corypha utan) are other natural hosts of CCCVd. Palm species of several genera, including Phoenix spp. and other species grown and/or cultivated in the EU, have been identified as potential hosts. The viroid is naturally transmitted at low rate by seeds and pollen and possibly by additional not yet identified natural transmission means. It can be transmitted through vegetative propagation applied to some palm species. Plants for planting including seeds of its hosts have been identified as the main entry pathway of CCCVd. Potential hosts of CCCVd are present in the EU, therefore establishment is possible. Should the pest establish in the EU, an impact is expected, with uncertainty on its magnitude. The Panel identified the susceptibility of palm species grown in the EU as a key uncertainty potentially affecting the conclusion of this pest categorisation. Nevertheless, the pest satisfies the criteria that are within the remit of EFSA to assess for this viroid to be regarded as potential Union quarantine pest.

Sensitivity of seed germination to water stress in high-altitude populations of a threatened palm species.

Divergence in seed germination patterns among populations of the same species is important for understanding plant responses to environmental gradients and potential plant sensitivity to climate change. In order to test the responses to flooding and decreasing water potentials we germinated and grew seeds of three habitats of Euterpe edulis Mart. occurring along an altitudinal gradient, over a period of three years. Seed germination and root growth were evaluated under different water availability treatments: control, flood, -0.4MPa, -0.8MPa, for 2012, 2013 and 2014 years, and in the last year of the experiment (2014), -1.0MPa and -1.5MPa. Seeds of the montane habitat did not germinate in the flood treatment. Seed germination of all three habitats decreased in the -1.5MPa treatment. Montane habitat had the lowest seed germination at -1.5MPa. Time required for half of the seeds to germinate increased up to -0.8MPa. Seeds of montane habitats germinated slower in all the treatments. The only difference observed in seed germination synchrony was an increase in submontane population in flooding treatment. However, synchrony decreased at the lowest water potential treatments. Roots of montane population were more vigorous in most treatments, except in -0.8 MPa. The unusual ability of seeds to germinate at low water potentials might be related to early seed germination at the onset of the rainy season, potentially decreasing seed predation pressure. Seeds of the montane population were more sensitive to both types of water stress. A predicted increase in the frequency and intensity of extreme high rainfall or drought events may predispose early stages of this population to adverse factors, which might negatively affect population viability along elevational in future climate change scenarios.

Recovering the urban forest: The role of trees, tree culture, and place attachment before and after Hurricane Harvey

Trees can be powerful symbols that contribute to the production and consumption of places. Disaster events, such as hurricanes, alter the physical landscape, causing tree damage and loss. In places with strong tree cultures, the reforestation of damaged landscapes becomes an implicit element of recovery plans; however, less is known about the implications of tree loss to community recovery. In 2017, Hurricane Harvey made landfall near the coastal communities of Rockport and Fulton, Texas. Rockport-Fulton, known for its beach tourism, is home to a remnant live oak (Quercus virginiana) forest shaped by coastal onshore winds. Many of Rockport-Fulton’s windswept oaks were damaged or lost along with native and non-native palm trees. Rockport-Fulton’s history is imbued with stories situated around its oak forest. Drawing from multiple sources and participant observations from repeated site visits, we analyzed references to Rockport-Fulton’s trees in news media, organizational communications, and public exhibits before and after Harvey to understand the area’s tree culture and its associated discourses. We also interviewed tourists, business owners, and community members nine months after Harvey to understand their perceptions of recovery efforts. Our findings show that tree narratives pre- and post-Harvey amplify social-ecological systems definitions of resilience and that tree loss was a dominant theme in the recovery process for all participants. Yet we also found that tourists discussed the damage to palm trees, whereas community members focused on the loss of live oaks. Despite these preferences, trees available through replanting efforts contained few live oak and palm species; furthermore, recovery plans did not amplify trees in recovery strategies. Overall, our findings highlight the importance of replanting trees during the disaster recovery process in a way that not only enhances local biodiversity but also reaffirms place characteristics to meet community members’ and visitors’ expectations.

Potential cultivation areas of Euterpe edulis (Martius) for rainforest recovery, repopulation and açai production in Santa Catarina, Brazil

Euterpe edulis is an endangered palm species that provides the most important non-timber forest product exploited in its natural habitat, the Brazilian Atlantic Forest hotspot1,4. From 1991 to 2017, pasturelands, agriculture, and monoculture of tree plantations were responsible for 97% of Atlantic Forest deforested areas in Brazil and Santa Catarina was one of the Brazilian states with the greatest loss of forest area14. In the last decade, E. edulis fruits reached their highest commercial value, producing the southeastern equivalent of Amazonian ‘‘açai’’ (Euterpe oleracea)5,7,8. As a shade-tolerant species, E. edulis adapts very well to agroforestry systems8,10. To evaluate potential areas for cultivation of E. edulis through agroforestry systems, we developed and applied a spatial model for mapping suitable areas. To accomplish this, we analyzed multisource biophysical data and E. edulis distribution data from the Forest Inventory of Santa Catarina. We identified two areas with potential occurrence of the species, one in the domains of coastal Dense Ombrophilous Forest where the species is more common and another in the domains of inland Deciduous Seasonal Forest where its occurrence was suspected, but not proven, until 2021. Today, Deciduous Seasonal Forest is the most fragmented and impacted by agriculture. Our model, together with confirmed areas of occurrence, indicates that deciduous seasonal forest region should be prioritized for production and recovery of E. edulis through agroforestry systems.

A new bluish-leaved Syagrus (Arecaceae) from an overlooked OCBIL in the Espinhaço Range (Brazil)

Background and aims – This study is part of ongoing research on the Arecaceae Flora of the Serra do Cabral, an isolated massif in the southwest of the Espinhaço Range in Minas Gerais State. Because of the isolation of the massif, the area has a rich biodiversity and a high level of endemism. While searching for populations of the rare and critically endangered Syagrus cabraliensis, a new bluish-leaved palm species was discovered and it is described here. Material and methods – The new species’ morphology is described based on field collections. The pinnae were analysed using SEM and LM cross- and longitudinal sections following default methodology. In addition, we compared the species to S. cabraliensis and provided ecological notes and a conservation status assessment. Key results – Syagrus carvalhoi resembles S. cabraliensis but they can easily be distinguished by morphoanatomical characters. Both species occur non-sympatrically in the Serra do Cabral, in contrasting microhabitats: S. carvalhoi in the southern quartzitic campos rupestres and S. cabraliensis in the northern ferruginous campos rupestres. A key to the known grass-like Syagrus species from the massif is provided. Based on the restricted area of occurrence and the anthropogenic threats, Syagrus carvalhoi is assessed as critically endangered. Conclusion – Syagrus carvalhoi is the second grass-like endemic Syagrus species from the Serra do Cabral and presents rare characters within the genus (grass-like aspect, colonial habit, flowers in tetrads, and the stem forking at or below the ground). This discovery corroborates that this isolated OCBIL is a home for endemic and rare palm species. The Serra do Cabral massif has proved a source of morphological and anatomical novelties in Arecaceae, affecting the taxonomy and understanding of the evolution and ecology of palms. Our results reinforce the notion that it is important to conserve this area with rich and rare biodiversity but under alarming and unprecedented threats.

Testing species relationships and delimitation in the Amazonian hyperdominantAstrocaryumsectionHuicungo(Arecaceae) using chloroplast data from genome skimming

AbstractHyperdominant trees in Amazonia account for half of the individual trees (>10 cm dbh) in the forest, and thus play a crucial role in ecosystem dynamics. However, several of these widespread hyperdominant species may be complexes hiding cryptic diversity that can affect species richness estimates and conservation priorities. Here, we study the intraspecific variation ofAstrocaryum murumuru(Arecaceae), a keystone and hyperdominant species in Amazonia, also known asAstrocaryumsect.Huicungo, a complex of 15 understory to subcanopy palm species. Using chloroplast DNA from genome skimming (>66 kbp alignment) in a Bayesian framework, we present evidence thatA. sect.Huicungorepresents three separately evolving lineages, suggesting that the section is not a single hyperdominant species, and that the 15 morphology‐based species may be an over‐representation. Genome skimming chloroplast data did not fully resolve the species‐level phylogenetic relationships inA. sect.Huicungomostly because of gene discordance and the paraphyly of most species. Contrary to a previous nuclear‐based phylogenetic analysis, the chloroplast genomic data did not recoverA. sect.Huicungomonophyletic, but yielded monophyly in an increased number of species (six) in the complex. Interspecific phylogenetic relationships showed a geographic pattern, and the traditional morphology‐based classification was not supported. Our phylogenomic results are discussed in light of earlier phylogeographical studies using Sanger sequencing. Our findings show the utility of genome skimming data in species delimitation analyses to uncover intraspecific variation of hyperdominant species in Amazonia, the largest evergreen tropical forest.

Management of trees and palms in swidden fallows by the Kichwa people in the Ecuadorian Amazon

IntroductionThe chakra is a cropping system used by the indigenous Kichwa people of the Ecuadorian Amazon that is advocated as a sustainable form of agriculture that ensures food production without impeding ecosystem functioning. Trees and palms are central to the benefits obtained from chakras, however, little is known about the management of these trees and palms. In this research we aimed to understand how the Kichwa people manage these species in chakras and what drives them to do so. Material and methodsWe conducted participatory observation research in three Kichwa communities during which we researched 18 chakras belonging to different households. In each chakra we identified the tree and palm species, counted their number, and measured their diameter at 1.3 m aboveground. Additionally, each household was interviewed on the use and management of these species. Results and discussionA total of 740 individual trees and palms were inventoried. Nearly all species in chakras were being actively managed, with the reduction of competition and the protection of seedlings being the most applied practices. This appears to be driven mainly by utilitarian values, as most species were used, most commonly for food and construction. Previous studies indicated that agroecological and mythical values also incite the management of trees and palms, which was not the case in this study. This difference is probably because of cultural erosion or cultural gender roles that affected data acquisition. ConclusionsThree important implications arise from this research: 1) future research should acknowledge and adequately address the large variation that exists among chakras, especially regarding their differences in number and size of trees and palms; 2) trees and palms in chakras should not be assumed to be managed inherently sustainably; 3) the understanding that economic and utilitarian considerations induce active management of palms and trees in chakras can lead to effective conservation policies.

Trends and gaps in the literature on native palms of the Brazilian Atlantic Forest

AbstractPalms (Arecaceae) exert great relevance to the structure and functioning of tropical forest ecosystems, in addition to comprise key resources for frugivorous animals. However, many species are currently at risk of extinction due to overexploitation and/or habitat loss. Our study aimed to perform a systematic review with a scientometric approach of all 78 native palm species of the Brazilian Atlantic Forest, seeking to identify the best‐studied species and regions, main studied topics, overall patterns, trends and gaps in scientific research associated with this botany family. In total, studies were carried out for 48 species belonging to 10 genera, with the number of studies exponentially increasing from the 70s and exhibiting great difference in the number of publications among species. Euterpe edulis was the most studied species (n = 274), followed by Acrocomia aculeata (n = 205), whereas Bactris bahiensis (1), Geonoma litoralis (1), Syagrus santosii (1) and Trithrinax acanthocoma (0) comprised the less studied species. The largest number of studies was carried out in the south‐eastern states of Brazil. Regarding the type of studies, 34% and 27% were related to biochemical properties and ecological processes, respectively, while studies on entomology (n = 26), tissue culture (n = 23) and taxonomy (n = 7) showed the lowest number of studies. Given the key role of palms in tropical forests, our study suggests that future research should focus on less studied species, including Desmoncus spp., Geonoma spp. and Trithrinax sp., and on some less studied areas like the north‐east portion of the Atlantic Forest.

Paternity Analyses for the Planning of SIT Projects against the Red Palm Weevil

The red palm weevil Rhynchophorus ferrugineus is an invasive pest from southeastern Asia and Melanesia that has spread widely across the Middle East and the Mediterranean Basin over the last 30 years. Its endophagous larvae cause huge amounts of damage to several palm tree species from the Arecaceae family. Many of these palms are economically important for agricultural and ornamental purposes. Therefore, a lot of attention has recently been focused on studying this species with the aim of identifying sustainable and effective eradication strategies. Sterile insect techniques are biological control strategies that are currently being investigated for their potential to eradicate this pest in selected invasion areas. Mating system features (e.g., polyandry and related features) can affect the success and suitability of these approaches. The main goal of this research was to assess the performance of a previously developed microsatellite panel in terms of the paternity assignment of progeny from laboratory mating experiments. Using a simulation approach, we evaluated the reliability of the microsatellite markers in the paternity tests both in complex laboratory experiment scenarios and on the progeny of wild-caught gravid females to help future studies on the RPW mating system. As a case study of the simulation results, we performed two double-mating experiments, genotyped the progeny and estimated the P2 values to compare to the expected progeny genotypes according to the crossing scheme of each experiment. The results of our simulations on laboratory experiments showed that it was possible to carry out paternity assignments for all progeny with reliable statistical confidence using our 13 microsatellites set. On the contrary the low genetic variability measured in red palm weevil populations in invaded areas made the resolution power of our loci too low to carry out paternity analyses on natural populations. Results of laboratory crossing were completely congruent with the expectations from the Mendelian laws.