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A Family of Transglutaminases Is Essential for the Development of Appressorium-Like Structures and Phytophthora infestans Virulence in Potato
Get PDFTransglutaminases (TGases) are enzymes highly conserved among prokaryotic and eukaryotic organisms, where their role is to catalyze protein cross-linking. One of the putative TGases of Phytophthora infestans has previously been shown to be localized to the cell wall. Based on sequence similarity, we were able to identify six more genes annotated as putative TGases and show that these seven genes group together in phylogenetic analysis. These seven proteins are predicted to contain both a TGase domain and a MANSC domain, the latter of which was previously shown to play a role in protein stability. Chemical inhibition of TGase activity and silencing of the entire family of the putative cell wall TGases are both lethal to P. infestans, indicating the importance of these proteins in cell wall formation and stability. The intermediate phenotype obtained with lower drug concentrations and less efficient silencing displays a number of deformations to germ tubes and appressoria. Both chemically treated and silenced lines show lower pathogenicity than the wild type in leaf infection assays. Finally, we show that appressoria of P. infestans possess the ability to build up turgor pressure and that this ability is decreased by chemical inhibition of TGases.Copyright (c) 2025 The Author(s). This is an open access article distributed under the CC BY 4.0 International license
Global Methane Budget 2000-2020
Get PDFUnderstanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. CH4 is the second most important human-influenced greenhouse gas in terms of climate forcing after carbon dioxide (CO2), and both emissions and atmospheric concentrations of CH4 have continued to increase since 2007 after a temporary pause. The relative importance of CH4 emissions compared to those of CO2 for temperature change is related to its shorter atmospheric lifetime, stronger radiative effect, and acceleration in atmospheric growth rate over the past decade, the causes of which are still debated. Two major challenges in quantifying the factors responsible for the observed atmospheric growth rate arise from diverse, geographically overlapping CH4 sources and from the uncertain magnitude and temporal change in the destruction of CH4 by short-lived and highly variable hydroxyl radicals (OH). To address these challenges, we have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to improve, synthesise, and update the global CH(4 )budget regularly and to stimulate new research on the methane cycle. Following Saunois et al. (2016, 2020), we present here the third version of the living review paper dedicated to the decadal CH4 budget, integrating results of top-down CH4 emission estimates (based on in situ and Greenhouse Gases Observing SATellite (GOSAT) atmospheric observations and an ensemble of atmospheric inverse-model results) and bottom-up estimates (based on process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations). We present a budget for the most recent 2010-2019 calendar decade (the latest period for which full data sets are available), for the previous decade of 2000-2009 and for the year 2020. The revision of the bottom-up budget in this 2025 edition benefits from important progress in estimating inland freshwater emissions, with better counting of emissions from lakes and ponds, reservoirs, and streams and rivers. This budget also reduces double counting across freshwater and wetland emissions and, for the first time, includes an estimate of the potential double counting that may exist (average of 23 Tg CH4 yr(-1)). Bottom-up approaches show that the combined wetland and inland freshwater emissions average 248 [159-369] Tg CH4 yr(-1) for the 2010-2019 decade. Natural fluxes are perturbed by human activities through climate, eutrophication, and land use. In this budget, we also estimate, for the first time, this anthropogenic component contributing to wetland and inland freshwater emissions. Newly available gridded products also allowed us to derive an almost complete latitudinal and regional budget based on bottom-up approaches. For the 2010-2019 decade, global CH4 emissions are estimated by atmospheric inversions (top-down) to be 575 Tg CH4 yr(-1) (range 553-586, corresponding to the minimum and maximum estimates of the model ensemble). Of this amount, 369 Tg CH4 yr(-1) or similar to 65 % is attributed to direct anthropogenic sources in the fossil, agriculture, and waste and anthropogenic biomass burning (range 350-391 Tg CH4 yr(-1) or 63 %-68 %).For the 2000-2009 period, the atmospheric inversions give a slightly lower total emission than for 2010-2019, by 32 Tg CH4 yr(-1) (range 9-40). The 2020 emission rate is the highest of the period and reaches 608 Tg CH4 yr(-1) (range 581-627), which is 12 % higher than the average emissions in the 2000s. Since 2012, global direct anthropogenic CH4 emission trends have been tracking scenarios that assume no or minimal climate mitigation policies proposed by the Intergovernmental Panel on Climate Change (shared socio-economic pathways SSP5 and SSP3). Bottom-up methods suggest 16 % (94 Tg CH4 yr(-1)) larger global emissions (669 Tg CH4 yr(-1), range 512-849) than top-down inversion methods for the 2010-2019 period. The discrepancy between the bottom-up and the top-down budgets has been greatly reduced compared to the previous differences (167 and 156 Tg CH4 yr(-1) in Saunois et al. (2016, 2020) respectively), and for the first time uncertainties in bottom-up and top-down budgets overlap. Although differences have been reduced between inversions and bottom-up, the most important source of uncertainty in the global CH4 budget is still attributable to natural emissions, especially those from wetlands and inland freshwaters. The tropospheric loss of methane, as the main contributor to methane lifetime, has been estimated at 563 [510-663] Tg CH4 yr(-1) based on chemistry-climate models. These values are slightly larger than for 2000-2009 due to the impact of the rise in atmospheric methane and remaining large uncertainty (similar to 25 %). The total sink of CH4 is estimated at 633 [507-796] Tg CH4 yr(-1) by the bottom-up approaches and at 554 [550-567] Tg CH4 yr(-1) by top-down approaches. However, most of the top-down models use the same OH distribution, which introduces less uncertainty to the global budget than is likely justified. For 2010-2019, agriculture and waste contributed an estimated 228 [213-242] Tg CH4 yr(-1) in the top-down budget and 211 [195-231] Tg CH4 yr(-1) in the bottom-up budget. Fossil fuel emissions contributed 115 [100-124] Tg CH4 yr(-1) in the top-down budget and 120 [117-125] Tg CH4 yr(-1) in the bottom-up budget. Biomass and biofuel burning contributed 27 [26-27] Tg CH4 yr(-1) in the top-down budget and 28 [21-39] Tg CH4 yr(-1) in the bottom-up budget. We identify five major priorities for improving the CH4 budget: (i) producing a global, high-resolution map of water-saturated soils and inundated areas emitting CH4 based on a robust classification of different types of emitting ecosystems; (ii) further development of process-based models for inland-water emissions; (iii) intensification of CH4 observations at local (e.g.FLUXNET-CH4 measurements, urban-scale monitoring, satellite imagery with pointing capabilities) to regional scales (surface networks and global remote sensing measurements from satellites) to constrain both bottom-up models and atmospheric inversions; (iv) improvements of transport models and the representation of photochemical sinks in top-down inversions; and (v) integration of 3D variational inversion systems using isotopic and/or co-emitted species such as ethane as well as information in the bottom-up inventories on anthropogenic super-emitters detected by remote sensing (mainly oil and gas sector but also coal, agriculture, and landfills) to improve source partitioning. The data presented here can be downloaded from 10.18160/GKQ9-2RHT (Martinez et al., 2024)
Finnish forest-related laws need to acknowledge climate change risks and integrate adaptive strategies to enhance resiliency
Get PDFForests provide critical ecosystem services, including soil protection, water regulation, biodiversity conservation, and absorbing carbon dioxide emissions. Forest resilience to climate change is crucial to sustaining these ecosystems. Here, we aim to review to what extent current forest legislation in Finland supports the adaptation of forests to climate change. We also reviewed non-binding legal documents such as forest strategies and government guidelines. Finnish forest laws addressed selection of genetic material for forest regeneration as well as the management of forest after abiotic damages. Climate change was not clearly mentioned in the laws. Current strategic documents assume that continuing existing forest management practices is sufficient to cope with climate change effects on forests. Overall, the present Finnish forest norms predominantly rely on a perception of low climate risk and business-as-usual management approach can sufficiently address the challenges posed by climate change. We strongly suggest that the Finnish forest norms need to adopt a comprehensive approach that acknowledges the potential risks of climate change and integrates adaptive strategies into forestry practices to enhance climate resilience
Limited evidence that body size shrinking and shape-shifting alleviate thermoregulatory pressures in a warmer world
Get PDFAmassing evidence indicates that vertebrates across the globe are shrinking and changing shape concurrent with rising temperatures. Ecogeographical theories assert that these changes should provide thermoregulatory benefits by easing heat dissipation, however, thermophysical models underpinning such theories are highly simplified and lack empirical validation. Using data from three temperature-manipulation experiments, we quantified the contributions of body size and appendage lengths toward thermoregulatory performance in Japanese quail, while simultaneously querying neutral plasticity as an alternative driver of avian shape-shifts. In the cold, body mass and leg length (here, tarsus length) influenced energy costs of warming, but only among juveniles. In the warmth, smaller body sizes, longer legs and longer bills independently reduced energy and water costs of cooling across ages, but whole-body phenotypes necessary to provide even moderate thermoregulatory benefits were rare (2.5%) and required large departures from allometry. Last, rearing in the warmth reduced body sizes and increased appendage lengths comparable to recent changes observed in nature, but emergent morphologies provided no clear thermoregulatory benefit. Our findings question whether shrinking and shape-shifting are indeed easing thermoregulation in birds or reflect selection for such. Neutral plasticity, or relaxed selection against small body size in juveniles, may better explain recent avian shape-shifting
Incorporating knowledge of allelopathic interactions can improve productivity and sustainability of crop rotations in the semi-arid tropics
Get PDFAllelopathy in rainfed crop production systems can be a boon or bane for smallholder farmers depending on their crop choices in intercrops, sequences, and rotations. Crop and weed allelopathy can lead to serious problems like poor germination, low crop stand, and reduced crop growth and productivity. Residual toxicity in soil due to allelopathic monocultures and detrimental impacts on ecosystems, human habitats and health are other problems caused by allelopathy. Allelopathy can be exploited to control weeds, reduce herbicide use, avoid herbicide resistance, stimulate crop growth, and enhance nutrient availability. This review aims to provide practical knowledge that can improve the management of farming systems in the semi-arid tropics of the Indian subcontinent, a region prone to allelopathic effects induced by biotic and abiotic stresses. We focus on synergistic and antagonistic allelopathic effects of major cereals, legumes, oilseeds, commercial crops, and weeds and summarise the current knowledge on the mode of release and properties of allelochemicals in crops, residue management and their impacts on crops and weeds. We then list options to effectively suppress weeds, reduce risks of residual toxicity in soil and environmental hazards and outline synergistic crop rotations that reduce disease build up and eradicate parasitic weeds in rainfed production systems of the semi-arid tropics. Finally, we highlight research gaps to further improve and employ knowledge of allelopathy of weeds and crops for improved crop production, with reduced synthetic herbicide usage
Dödlighet hos vuxna älgar
Get PDFI det här arbetet analyserade vi orsaksspecifik dödlighet hos vuxna älgkor och älgtjurar (Alces alces) med hjälp av ett omfattande data set av 1021 GPS-märkta älgar (796 kor, 225 tjurar) geografiskt fördelade mellan Kronobergs och Norrbottens län under perioden 2003 - 2024. Det är första gången olika orsaker för dödlighet har skattats med en så stor individ-baserade empirisk datamängd och som omfattar olika områden längs en miljömässig gradient i Sverige. Vårt arbete visar på fyra huvudresultat: (1) Jakt utgjorde överlägsen största andelen av dödlighet även för GPS-märkta älgar och risken att dö till följd av jakt är relativ större för älgtjurar än för älgkor. (2) Älgkor och -tjurar skilde sig åt i sin risk att dö på grund av jakt, men också på grund av andra orsaker där korna tenderade att löpa en större risk att bli trafikdödade eller dö på grund av okända orsaker jämfört med älgtjurar. (3) Andelen av icke-mänsklig relaterade dödlighet (dvs ej jakt eller trafik) varierade mellan områden. Naturlig dödlighet tenderade att förekomma i högre grad i södra studieområden med störst variation i hemiboreala landskap söder om Limes norrlandicus. Utöver detta tenderade den okända dödligheten att utgöra en större andel hos älgar på Öland (Kalmar län) och vid Östermalma (Södermanlands län), samt för en del av studieområdena i Norrbottens län. (4) Vår analys av dödlighet utöver jakt, trafik och predation under det första året vi kunde följa en given GPSmärkt älg gav en övrig dödlighet på 3.2% (konfidensintervall: 2.1-4.4%). Vårt data innehöll fler kor än tjurar och vissa typer av dödsorsaker förekommer sällan. Denna snedfördelning kan medföra att kornas orsaksspecifiska dödlighet kan få mer vikt i analysen av konkurrerande dödsorsaker eftersom dessa utgjorde en större andel av vår data. Risken för en given dödsorsak varierade mycket för både kor och tjurar mellan olika områden, framför allt för sällsynta dödsorsaker. Detta medförde stora och överlappande konfidensintervall i många fall som i sin tur försvårade möjligheten att hitta tydliga statistiska skillnader
Modeling crop yield response to nitrogen inputs in different crop rotations using data from long-term experiments
Get PDFProductive and resource-efficient crop production systems are essential to build sustainable food systems. Specific crops and well-designed diverse crop rotations can provide several benefits, including improved food system sustainability. Crop growth models that capture these benefits require detailed and rarely available input data, making them impossible to implement in quantitative research at the scale of national or subnational food systems. Instead, we need simple yet robust cropping system models accounting for the rotated crops that require limited input data and can be employed in food system models. Here, we present a proof-of-concept solution to this challenge. Using data from long-term field experiments in Sweden and Poland, we establish robust relationships between the input of nitrogen and output of crude protein, ruminant metabolizable energy, and harvested dry matter across whole crop rotations with and without leys. These three output metrics capture key aspects of productivity from a food-system perspective. To demonstrate potential applications in food system modeling or life cycle assessment, we calculate carbon and land footprints of outputs. Compared with rotations without leys, crop rotations with leys had higher outputs of crude protein and dry matter, at least at high nitrogen inputs. Productivity of ruminant metabolizable energy did not differ when including leys. This approach provides a promising avenue for further research at the intersection of crop system and food system science, exploiting the wealth of information collected in long-term field experiments thus far
Birth of puppies after endoscopically guided transcervical intrauterine insemination with cryopreserved epididymal canine spermatozoa
Get PDFBackgroundThe preservation of epididymal spermatozoa is useful for saving important genetic material from valuable individuals who die suddenly or have to be castrated. The birth of puppies after artificial insemination with canine epididymal spermatozoa has been reported in only a few cases. Surgical insemination with frozen-thawed epididymal spermatozoa has resulted in pregnancies, but usually with low conception rates. Freshly collected and chilled epididymal canine semen has also resulted in conception after vaginal insemination. Considering the invasiveness of surgical insemination and the almost unlimited storage time of cryopreserved spermatozoa, transcervical intrauterine insemination with frozen-thawed epididymal spermatozoa would be beneficial. It has the potential to use genetic material that would otherwise be lost, both in domestic dogs and for the preservation of wild threatened canids.Case presentationA 7-year-old, 20 kg male hunting dog was injured by a wild boar during hunting, and euthanasia was recommended for welfare reasons. Because the dog was a hunting champion in a numerically very small breed, the owner wanted to have spermatozoa preserved for future breeding. The dog was anaesthetised, both testes were removed, and the dog was thereafter euthanized. Spermatozoa from both caudae epididymides were released in a prewarmed Uppsala extender with the mincing method. The samples were routinely frozen with the Uppsala method. A half-filled straw was used for test thawing, resulting in 20% motile spermatozoa with slow progressive movement. Three years later, a 23-month-old bitch of the same breed was inseminated with endoscopically guided transcervical intrauterine sperm deposition. She was inseminated once, five days after a serum progesterone value of 6.9 nmol/mL was reached, and two days after a value of 24.8 nmol/mL was reached. The total amount of cryopreserved spermatozoa was used (a total dose of 1087 x 106 spermatozoa and 217 x 106 progressively motile spermatozoa remaining after test thawing). Eight puppies were born 59 days after insemination.ConclusionsAlthough rarely reported, artificial insemination with cryopreserved epididymal canine spermatozoa is an alternative in preserving valuable genetic animals when a male is injured beyond recovery
Assessing Single-Trait and Multitrait Genomic Prediction Model Abilities Including Significant GWAS Markers for Fusarium Head Blight Disease Resistance in Wheat (Triticum aestivum)
Get PDFDisease resistance traits are complex and quantitative in nature. Breeders regularly evaluate multiple important traits across diverse environments to employ them in genomics-assisted breeding. In this study, we evaluated the prospects of genomic prediction models by incorporating genome-wide association study (GWAS) results into single-trait and multitrait genomic prediction scenarios, using two distinct panels: the NMBU panel and the GRAMINOR panel. A standard genomic prediction model (Base) and the Base model with the addition of significant GWAS markers as fixed covariates (Base + GWAS) were tested on both panels. The predictive ability of models was measured in terms of prediction ability by using Pearson's correlation method. An improvement of 0.05% to as high as a two-fold improvement was observed in both the panels for single-trait and multitrait scenarios. In general, multitrait models outperformed single-trait models regardless of whether the GWAS markers were included. This study further concludes that multitrait-based genomic predictions are superior to single trait-based ones when the associated traits are used and are well correlated
Submersed Aquatic Vegetation Enhances Density and Diversity of Epifaunal Invertebrates Compared to Filamentous Mats in the Central Baltic Sea
Get PDFSubmersed aquatic vegetation (SAV) provides essential habitat and food to numerous coastal invertebrate species. In the eutrophic Baltic Sea, fast-growing drifting algae form extensive mats that can negatively impact SAV. However, these mats also offer additional habitat and food to epifauna. The aim of this study was to assess the effects of SAV and filamentous mats on epifaunal communities in shallow soft-bottom habitats around Gotland, Sweden, in the central Baltic Sea. We used generalised linear models (GLMs) to evaluate the influence of SAV vertical structure, biomass and macrophyte species richness (including macroalgae) and filamentous mat biomass on epifaunal community properties as well as on those of key grazer species. Diversity, vertical structure and biomass of SAV were positively associated with higher total epifaunal abundance and greater abundance gastropod grazers. In contrast, filamentous mats only increased gastropod abundance and biomass. In addition to introducing a rapid tool for quantifying vegetation structural complexity, this study highlights the selective effects of different habitat types on invertebrate communities in a relatively understudied region of the Baltic Sea. As warming temperatures and eutrophication promote filamentous mat growth, reducing nutrient pollution and protecting SAV will be crucial for sustaining abundant and diverse epifaunal communities