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Oil Palm Germplasm Resources and Their Conservation: Advances and Challenges for In Vitro Conservation
No full textIn vitro germplasm conservation provides an alternative method for preserving plant species that are vulnerable to natural hazards or for which in situ conservation is costly and challenging to manage. This review examines the significance and challenges associated with various in vitro conservation methods. It also provides an overview of the current advances in cryopreservation technology for oil palm. In vitro conservation approaches include two strategies: medium-term conservation, in which plants are maintained through the slow growth of explants, facilitated by the gradual release of nutrients, and low-temperature storage. The second approach involves long-term preservation via cryopreservation in liquid nitrogen. Cryopreservation enables the storage of pollen, calli, somatic embryos, and zygotic embryos. Significant progress has been made in cryopreservation, which was initially limited to cold-tolerant species. New techniques focus on conserving sensitive species, such as oil palm, through rapid dehydration and vitrification procedures using various plant materials, particularly polyembryoids and zygotic embryos. Additionally, hardening of plant material is to be induced through pre-culture techniques to enhance their survival under osmotic stress and ultralow temperature. The mechanisms underlying the adaptability of various plant materials, i.e., somatic embryoids and zygotic embryos under cryopreservation, need to be understood
Commodity risk assessment of debarked conifer wood chips fumigated with sulfuryl fluoride from the US
No full textThe European Commission requested the EFSA Panel on Plant Health to deliver a risk assessment on the likelihood of pest freedom from regulated EU quarantine pests, with emphasis on Bursaphelenchus xylophilus and its vectors Monochamus spp. of debarked conifer wood chips fumigated with sulfuryl fluoride as proposed by the United States (US) and as outlined in ISPM 28 - PT23 of sulfuryl fluoride (SF) fumigation treatment for nematodes and insects in debarked wood. The assessment considered the different phases in the wood chips' production, with special emphasis on the SF treatment. In addition to B. xylophilus and its vectors Monochamus spp., 22 EU quarantine pests and protected zone quarantine pests, some of which are regulated as groups of pests by the Commission Implementing Regulation (EU) 2019/2072, are present in the US and are potentially associated with the commodity. For these pests an expert judgement is given on the likelihood of pest freedom taking into consideration the available scientific information and technical information provided by the US, including uncertainties associated with the assessment. The likelihood of pest freedom varies among the pests evaluated, with B. xylophilus being the pest most frequently expected on the commodity. The Expert Knowledge Elicitation (EKE) indicated with 95% certainty that between 9491 and 10,000 m3 of debarked conifer wood chips treated with SF per 10,000 m3 will be free from B. xylophilus, and that between 9987 and 10,000 m3 of wood chips per 10,000 m3 will be free from Monochamus spp. Technical elements which are critical for a successful treatment and for minimising the presence of Union quarantine pests on the commodity are identified and described in the opinion. In particular, it is important to note that SF treatments are generally less effective in eliminating fungi than insects, the required parameters of the fumigation should be met at all points of the pile of wood chips and the time of storage of wood chips before treatment should be kept as short as possible because B. xylophilus can easily reproduce and spread throughout the pile under conducive conditions
Commodity risk assessment of Salix caprea and Salix cinerea plants from the UK
No full textThe European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'High risk plants, plant products and other objects'. This Scientific Opinion covers plant health risks posed by plants of Salix caprea and Salix cinerea imported from the United Kingdom (UK) as: (a) bundles of 1- to 2-year old cuttings/graftwood, (b) 1- to 7-year-old bare root plants, (c) 1- to 2-year-old cell grown plants and (d) 2- to 15-year-old plants in pots, taking into account the available scientific information, including the technical information provided by the UK. All pests associated with the commodities were evaluated against specific criteria for their relevance for this opinion. Two EU protected zone quarantine pests, i.e. Bemisia tabaci (European populations) and Entoleuca mammata, and one EU quarantine pest, i.e. Phytophthora ramorum (non-EU isolates), fulfilled all relevant criteria and were selected for further evaluation. For the selected pests, the risk mitigation measures described in the technical dossier from the UK were evaluated. Expert judgements were given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pests, including uncertainties associated with the assessment. The age of the plants was considered, reasoning that older trees are more likely to be infested mainly due to longer exposure time and larger size. The degree of pest freedom varies between the pests evaluated, with P. ramorum being the pest most frequently expected on the imported plants. The Expert Knowledge Elicitation (EKE) indicated with 95% certainty that between 9738 and 10,000 rooted S. caprea and S. cinerea plants in pots (2 to 15-year-old) per 10,000 will be free from P. ramorum
Commodity risk assessment of Berberis thunbergii plants from the UK
No full textThe European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as 'high risk plants, plant products and other objects'. Taking into account the available scientific information, including the technical information provided by the applicant country, this Scientific Opinion covers the plant health risks posed by the following commodities: Berberis thunbergii, bare root plants (up to 3 years old), whips (up to 2 years old) and rooted plants in pots (up to 4 years old) imported into the EU from the UK. A list of pests potentially associated with the commodities was compiled. The relevance of each pest was assessed based on evidence following defined criteria. One EU quarantine pest (Phytophthora ramorum (non-EU isolates)), one protected zone quarantine pest (Bemisia tabaci (European populations)) and one non-quarantine pest (Phytophthora kernoviae) were selected for further evaluation. For the selected pests, the risk mitigation measures implemented in the UK and specified in the technical dossier were evaluated taking into account the factors reducing their efficacy. For these pests, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including uncertainties associated with the assessment. The degree of pest freedom varies between the pests evaluated, with P. ramorum being the pest most frequently expected on the evaluated imported commodities. Expert Knowledge Elicitation indicated, with 95% certainty, that between 9975 and 10,000 per 10,000 B. thunbergii rooted plants in pots would be free from P. ramorum
Metabolomic and transcriptomic insights into the mechanism of sugar and acid accumulation in the pulp of sour- and sweet-tasting Baccaurea ramiflora Lour.
No full textIntroduction: The taste differences between sour-tasting (LR) and sweet-tasting (BR) fruits of Baccaurea ramiflora Lour. are pronounced, but the underlying molecular mechanisms remain unclear. Methods: This study employed a combined metabolomic and transcriptomic analysis to elucidate the metabolic pathways governing this flavour variation. Results: Metabolomic profiling identified D-(+)-glucose and citric acid as the key taste determinants, with BR fruits exhibiting a significantly higher sugar-to-acid ratio than LR fruits. Transcriptomic data revealed that invertase (INV) activity correlated with D-glucose levels, whereas sucrose synthase (SUS) and sucrosephosphate synthase (SPS) were associated with sucrose accumulation. In fully mature BR fruits, the suppressed expression of INV suggested that reduced sucrose hydrolysis contributes to their enhanced sweetness. Conversely, in LR fruits, elevated expression of hexokinase (HK) indicated higher glucose utilization. Furthermore, the expression of genes involved in organic acid metabolism— including citrate synthase (CS), aconitase (ACO), and NADP-malic enzyme (NADP-ME)—was found to regulate the content of citric and malic acids. Discussion: These findings advance our understanding of the molecular basis of flavour formation in B. ramiflora, and provide potential targets for the breeding and biotechnological improvement of fruit taste
Factors Affecting CO2, CH4, and N2O Fluxes in Temperate Forest Soils
No full textGreenhouse gas (GHG) fluxes from forests, including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), are regulated by complex interactions of abiotic and biotic factors. A better understanding of these interactions involving GHGs can help manage forests and enhance their sequestration potential. This review examines how soil properties (moisture, temperature, and pH) and tree species-specific traits (litter quality, carbon storage, and microbial regulation) interactively control GHG dynamics in temperate forest soils, moving beyond a single-factor perspective. This literature review confirms that temperate forest soils are CH4 sinks and sources of CO2 and N2O; however, flux direction and magnitude differ across spatial and temporal scales. CH4 fluxes show high spatial variability and are sensitive to biogeochemical conditions. While soil temperature and moisture are well studied, their combined effects with site-specific variables such as substrate availability, soil texture, and canopy structure remain underexplored. Tree litter plays a dual role: chemically influencing microbial physiological/functional traits through priming, thereby affecting CO2 and N2O, and physically limiting CH4 diffusion. These mechanisms collectively determine whether soils act as GHG sources or sinks, and future research should account for how litter priming may override their carbon sink function while integrating site-specific factors to improve GHG predictions and forest management
Strains of Aureobasidium pullulans from Extreme Environments: New Potential Biocontrol Agents?
No full textExtreme environments are a largely unexplored reservoir of microbial diversity, with a remarkable potential to be exploited in agriculture. One hundred and seventeen yeast isolates, derived from different ecosystems in Italy, Sweden, Algeria, and France, were molecularly identified, and the most represented genus was Aureobasidium (57%). A phylogenetic analysis based on a multi-locus sequence typing (ITS, ELO, EF-1alpha) was conducted to characterize the black yeasts' population. To investigate A. pullulans extremophilic and extremotolerant behaviour, different temperatures and pH, together with the enzymatic production, were evaluated. The strains were tested by in vitro and in vivo assays against the postharvest fungal pathogen Monilinia fructicola as potential biocontrol agents (BCAs). Results displayed a great ecological variability concerning strains' growth and cell production depending on different culture conditions. However, a remarkable thermotolerance aptitude was detected in almost all the strains. In particular, the strains belonging to Group 2 (Algerian Desert) and 3 (Alto Adige Region) showed, respectively, higher thermotolerance and biocontrol ability. These findings showed how some extreme environments could represent a promising source for new potential BCAs. However, further studies are needed to investigate the mechanisms of action of these putative BCAs for application during the postharvest phase
Fältinstruktion för nationell inventering av högmossar
No full textSverige har ett ansvar att rapportera areal, utbredning och status för Annex I-naturtyper till EU:s artikel 17. På uppdrag av Naturvårdsverket har NILS och THUF vidareutvecklat en statistisk design för att kunna erbjuda en inventering som på ett effektivt sätt samlar in data för Annex I-naturtyper för en adekvat artikel 17-rapportering. Fokus för inventeringarna är naturtyper som är underrepresenterade i andra nationella övervakningsprogram. I uppdraget ingår det att förändringar i areal och kvalitet ska kunna upptäckas för de naturtyper eller aggregeringar av naturtyper som respektive inventering fokuserar på. Data som sedan används i rapporteringen av naturtyperna i Annex I av EU:s Habitatdirektiv som rapporteras till EU vart sjätte år. Våra data används även för att följa upp de svenska Miljökvalitetsmålen.Nationella inventeringar av landskapet i Sverige – NILS, utgör idag ett generellt ramverk under vilket ett flertal nationella miljöövervakningsprogram samlas, NILS fjällinventering, NILS gräsmarksinventering, NILS lövskogsinventering, NILS Våtmarksinventering med fokus på högmossar och THUF havstrandsinventering (https://www.slu.se/om-slu/organisation/institutioner/skoglig-resurshushallning/miljoanalys/NILS/). Huvudfinansiär för NILS är Naturvårdsverket.Den här fältinstruktionen omfattar: • NILS våtmarksinventering som startade 2023 med fokus på högmossar. Det är en nationell inventering av alla typer av högmossar och inkluderar Annex I-naturtypen 7110 ”högmosse”, som definieras i ”Instruktion för Habitatinventering” (Gardfjell & Hagner 2019) och 7120 ”skadad högmosse” (Naturvårdsverket 2011a). Det finns dock även andra definitioner av högmossar vilket gör att vi inom inventeringen även registrerar detaljerade data för andra typer av mossar som är ≥ 0,5 m höga. Detta möjliggör att vi i efterhand kan omklassificera högmossarna enligt andra definitioner
Transcriptional Dynamics and Chromatin Accessibility in the Regulation of Shade-Responsive Genes in Arabidopsis
No full textBackground Open chromatin regions host DNA regulatory motifs that are accessible to transcription factors and the transcriptional machinery. In Arabidopsis, responses to light are heavily regulated at the transcriptional level. Shade, for example, can limit photosynthesis and is rapidly perceived by phytochromes as a reduction of red to far-red light ratio (LRFR). Under shade, phytochromes become inactive, enabling PHYTOCHROME INTERACTING FACTORs (PIFs), particularly PIF7, to promote genome-wide reprogramming essential for LRFR responses. An initial strong and fast regulation of shade-responsive genes is followed by attenuation of this response under prolonged shade.Results To determine whether the transcriptional response to shade depends on chromatin accessibility, we use ATAC-seq to profile the chromatin of seedlings exposed to short (1 h) and long (25 h) simulated shade. We find that PIF7 binding sites are accessible for most early target genes before LRFR treatment. The transcription pattern of most acute shade-responsive genes correlates with a rapid increase in PIF levels and chromatin association at 1 h, and its decrease at 25 h of shade exposure. For a small subset of acutely responding genes, PIFs also modulate chromatin accessibility at their binding sites early and/or late in the response to shade.Conclusions Our results suggest that in seedlings a state of open chromatin conformation allows PIFs to easily access and recognize their binding motifs, rapidly initiating gene expression triggered by shade. This transcriptional response primarily depends on a transient increase in PIF stability and gene occupancy, accompanied by changes in chromatin accessibility in a minority of genes
Using step selection functions to analyse human mobility using telemetry data in infectious disease epidemiology: a case study of leptospirosis
No full textBackground:Human movement plays a critical role in the transmission of infectious diseases, especially those with environmental drivers like leptospirosis-a zoonotic bacterial infection linked to mud and water contact. Using GPS loggers, we collected detailed telemetry data to understand how fine-scale movements can be analysed in the context of an infectious disease. Methods:We recruited individuals living in urban slums in Salvador, Brazil, to analyse how they interact with environmental risk factors such as domestic rubbish piles, open sewers, and a local stream. We aimed to identify differences in movement patterns inside the study areas by gender, age, and leptospirosis serological status. Step selection functions, a spatio-temporal model used in animal movement ecology, estimated selection coefficients to represent the likelihood of movement toward specific environmental factors. Results:With 128 participants wearing GPS devices for 24-48 hr, recording locations every 35 s during active daytime hours, we segmented movements into morning, midday, afternoon, and evening. Our results suggested women moved closer to the central stream and farther from open sewers compared to men, while serologically positive individuals avoided open sewers. Conclusions:This study introduces a novel method for analysing human telemetry data in infectious disease research.Funding:Funding provided by Wellcome Trust, UK Medical Research Council, Brazilian National Research Council, Reckitt Global Hygiene Institute, and National Institute of Allergy and Infectious Diseases