The distribution of self-incompatibility systems in angiosperms: the relationship between mating system diversity, life span, growth habit and latitude in a changing global environment.

BACKGROUND AND AIMS: There is ample theoretical and experimental evidence that angiosperms harbouring self-incompatibility (SI) systems are likely to respond to global changes in unique ways relative to taxa with other mating systems. In this paper, we present an updated database on the prevalence of SI systems across angiosperms and examine the relationship between the presence of SI and latitude, biomes, life-history traits and management conditions to evaluate the potential vulnerability of SI taxa to climate change and habitat disturbance. METHODS: We performed literature searches to identify studies that employed controlled crosses, microscopic analyses and/or genetic data to classify taxa as having SI, self-compatibility (SC), partial self-compatibility (PSC) or self-sterility (SS). Where described, the site of the SI reaction and the presence of dimorphic versus monomorphic flowers were also recorded. We then combined this database on the distribution of mating systems with information about the life span, growth habit, management conditions and geographic distribution of taxa. Information about the geographic distribution of taxa was obtained from a manually curated version of the Global Biodiversity Information Facility database, and from vegetation surveys encompassing 9 biomes. We employed multinomial logit regression to assess the relationship between mating system and life-history traits, management condition, latitude and latitude-squared using self-compatible taxa as the baseline. Additionally, we employed LOESS regression to examine the relationship between the probability of SI and latitude. Finally, by summarizing information at the family level, we plotted the distribution of SI systems across angiosperms including information about the presence of SI or dioecy, the inferred reaction site of the SI system when known, as well as the proportion of taxa in a family for which information is available. KEY RESULTS: We obtained information about the SI status of 5686 hermaphroditic taxa, of which 55% exhibited SC, and the remaining 45% harbour SI, self-sterility (SS), or PSC. Highlights of the multinomial logit regression include that taxa with PSC have a greater odds of being short- (OR=1.3) or long- (OR=1.57) lived perennials relative to SC ones, and that SS/SI taxa (pooled) are less likely to be annuals (OR=0.64) and more likely to be long-lived perennials (OR=1.32). SS/SI taxa had a greater odds of being succulent (OR=2.4) or a tree (OR=2.05), and were less likely to be weeds (OR=0.34). Further, we find a quadratic relationship between the probability of being SI with latitude: SI taxa were more common in the tropics, a finding that was further supported by the vegetation surveys which showed fewer species with SS/SI in temperate and northern latitudes compared to mediterranean and tropical biomes. CONCLUSIONS: We conclude that in the short-term habitat fragmentation, pollinator loss and temperature increases may negatively impact plants with SI systems, particularly long-lived perennial and woody species dominant in tropical forests. In the longer term, these and other global changes are likely to select for self-compatible or partially self-compatible taxa which, due to the apparent importance of SI as a driver of plant diversification across the angiosperm tree of life, may globally influence plant species richness.

Divergent structural leaf trait spectra in succulent versus non-succulent plant taxa.

BACKGROUND AND SCOPE: Plant functional traits are the result of natural selection to optimize carbon gain, leading to a broad spectrum of traits across environmental gradients. Among plant traits, leaf water storage capacity is paramount for plant drought resistance. We explored whether leaf-succulent taxa follow similar trait correlations as non-leaf-succulent taxa to evaluate whether both are similarly constrained by relationships between leaf water storage and climate. We tested the relationships among three leaf traits related to water storage capacity and resource use strategies in 132 species comprising three primary leaf types: succulent, sclerophyllous, and leaves with rapid returns on water investment - referred to as fast return. Correlation coefficients among specific leaf area (SLA), water mass per unit of area (WMA), and saturated water content (SWC) were tested, along with relationships between leaf trait spectra and aridity determined from species occurrence records. CONCLUSION: Both SWC and WMA at a given SLA were approximately 10-fold higher in succulent leaves than in non-succulent leaves. While SWC actually increased with SLA in non-succulent leaves, no relationship was detected between SWC and SLA in succulent leaves, although WMA decreased with SLA in all leaf types. A principal component analysis revealed that succulent-taxa occupied a widely different mean trait space than either fast-return (P < 0.0001) and sclerophyllous taxa (P < 0.0001) along the first PCA axis, that explained 63% of mean trait expression among species. However, aridity only explained 12% of the variation in PCA1 values. This study is among the first to establish a structural leaf trait spectrum in succulent leaf taxa and quantify contrasts in leaf water storage among leaf types relative to specific leaf area. Results show that trait coordination in succulent leaf taxa may not follow similar patterns as widely studied non-succulent taxa.

Context-dependent associations between heterozygosity and immune variation in a wild carnivore.

BACKGROUND: A multitude of correlations between heterozygosity and fitness proxies associated with disease have been reported from wild populations, but the genetic basis of these associations is unresolved. We used a longitudinal dataset on wild Galapagos sea lions (Zalophus wollebaeki) to develop a relatively new perspective on this problem, by testing for associations between heterozygosity and immune variation across age classes and between ecological contexts. RESULTS: Homozygosity by locus was negatively correlated with serum immunoglobulin G production in pups (0-3 months of age), suggesting that reduced genetic diversity has a detrimental influence on the early development of immune defence in the Galapagos sea lion. In addition, homozygosity by locus was positively correlated with total circulating leukocyte concentration in juveniles (6-24 months of age), but only in a colony subject to the anthropogenic environmental impacts of development, pollution and introduced species, which suggests that reduced genetic diversity influences mature immune system activity in circumstances of high antigen exposure. CONCLUSIONS: These findings demonstrate the environmental context-dependency of the phenotypic expression of immune variation, which is implicit in the theory of ecoimmunology, but which has been rarely demonstrated in the wild. They also indicate that heterozygosity may be linked to the maintenance of heterogeneity in mammalian immune system development and response to infection, adding to the body of evidence on the nature of the mechanistic link between heterozygosity and fitness.

Presence of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in Food-Producing and Companion Animals and Wildlife on Small-Holder Farms of Floreana Island, Galápagos Islands.

Background: Antimicrobial resistance (AR) has led to increasing human and animal morbidity and mortality and negative consequences for the environment. AR among Escherichia coli (EC) is on the rise, with serious concerns about extended-spectrum ß-lactamase-producing E. coli (ESBL-EC). In the Galápagos Islands, where antimicrobials are available without a prescription, growing demands for food production can drive antimicrobial use. Food producing animals are at the interface of wildlife and environmental health on the smallest human-inhabited Galápagos Island, Floreana. We sought to determine if ESBL-EC were present in Floreana Island farm animal species and nearby wildlife and the relatedness of ESBL-EC isolates identified. Materials and Methods: During July 4-5, 2022, we visited 8 multispecies farms, representing 75% of food-producing animal production on Floreana, and collected 227 fecal samples from farm animals and wildlife. Each sample was plated on MacConkey agar supplemented with cefotaxime (4 µg/mL). Results: ESBL-EC was isolated from 20 (9%) fecal samples collected from pigs (N = 10), chickens (N = 6), wildlife (N = 3), and dog (N = 1). All ESBL-EC isolates were from samples taken at three (38%) of the eight farms. Fifteen (75%) of the ESBL-EC isolates were from a single farm. All ESBL-EC isolates were multidrug resistant. The most prevalent ESBL genes belonged to the blaCTX-M group. Among the typeable isolates from the farm with the largest proportion of ESBL-EC isolates (N = 14), we observed nine unique pulsed-field gel electrophoresis (PFGE) patterns, with identical patterns present across pig and chicken isolates. PFGE patterns in the three farms with ESBL-EC isolates were different. Conclusions: These results lend support for future routine AR monitoring activities at the livestock-wildlife interface in Galápagos to characterize potential interspecies transmission of AR bacteria and AR genes in this unique protected ecosystem, and the related human, animal, and environmental health impacts, and to formulate interventions to reduce AR spread in this setting.

Undetection of vector-borne viruses in equids of Galapagos Islands.

Domestic species, including equids, were introduced in the Galapagos Islands in the XIX century. Equine vector-borne diseases are circulating in South America but their occurrence in the Galapagos Island was unknown. The objective of this study was to detect the occurrence of West Nile virus (WNV), Usutu virus (USUV) and equine infectious anemia virus (EIAV) in the four Galapagos Islands raising equids if they were present at a prevalence >1%. Serum samples were collected from 411 equids belonging to 124 owners from April to July 2019. All the results were negative to the ELISA tests used suggesting that WNV, USUV and EIAV are not circulating in the equine population of the Galapagos Islands.

Corrigendum: Geographical and life-history traits associated with low and high species richness across angiosperm families.

[This corrects the article DOI: 10.3389/fpls.2023.1276727.].

Assessing Livestock Production Practices on Small-Scale Multi-Species Farms Located on Floreana Island, Galápagos Islands.

Globally to date, established international standards for animal welfare, a priority of sustainable agriculture, have primarily focused on large-scale producers. However, across Latin America, including in Ecuador's Galápagos Islands, smallholder farms play a critical role in food safety and security. We assessed five basic animal welfare measures (feed and water access, shelter availability and housing systems, animal health management, animal behavior, and timely euthanasia) for poultry, pigs, and cattle on Floreana Island, Galápagos. Utilizing assessment standards from multiple US sources and international standards, we developed a questionnaire and used it to conduct in-depth interviews during 4-5 July 2022 with eight participating producers, representing 75% of animal agriculture on Floreana. While we identified opportunities to enhance competencies in animal health management and timely euthanasia, farms performed well in the other assessed measures. Future work should promote knowledge transfer and in-country capacity building in farm biosecurity, access to veterinary care, antimicrobial resistance surveillance, and euthanasia methods. Efforts to positively impact smallholder farm livelihoods in Galápagos-one of the most biodiverse and protected ecosystems on the planet-will sustainably support human health through the interconnected realms of animal health and welfare, wildlife and environmental health, and food safety and security.

A recent distemper virus outbreak in the growing canine populations of Galapagos Islands: a persistent threat for the endangered Galapagos Sea Lion.

Canine Distemper Virus (CDV) is a highly contagious virus that can cross mammalian species barriers and has widespread impacts on both domestic animals and wildlife populations. This study describes a recent outbreak of CDV in the Galapagos Islands in 2019. A total number of 125 dogs with clinical signs compatible with CDV were included in this study. Nasal swabs were taken and analyzed by RT-qPCR for the detection of CDV, resulting in a positivity rate of 74.4% (IC95%, 66-81%). Among the CDV positive dogs, 82.2% presented with respiratory signs, 48.8% neurological signs, and 28.9% gastrointestinal signs. CDV has been previously reported in the domestic canine population of the Galapagos Islands in 2001 and 2004. The current study shows how CDV is still a threat for the endemic and endangered Galapagos sea lion, despite recent policies for dog population control and CDV vaccination.

Geographical and life-history traits associated with low and high species richness across angiosperm families.

Introduction: The phenomenal expansion of angiosperms has prompted many investigations into the factors driving their diversification, but there remain significant gaps in our understanding of flowering plant species diversity. Methods: Using the crown age of families from five studies, we used a maximum likelihood approach to classify families as having poor, predicted or high species richness (SR) using strict consensus criteria. Using these categories, we looked for associations between family SR and i) the presence of an inferred familial ancestral polyploidization event, ii) 23 life history and floral traits compiled from previously published datasets and papers, and iii) sexual system (dioecy) or genetically determined self-incompatibility (SI) mating system using an updated version of our own database and iv) geographic distribution using a new database describing the global distribution of plant species/families across realms and biomes and inferred range. Results: We find that more than a third of angiosperm families (65%) had predicted SR, a large proportion (30.2%) were species poor, while few (4.8%) had high SR. Families with poor SR were less likely to have undergone an ancestral polyploidization event, exhibited deficits in diverse traits, and were more likely to have unknown breeding systems and to be found in only one or few biomes and realms, especially the Afrotropics or Australasia. On the other hand, families with high SR were more likely to have animal mediated pollination or dispersal, are enriched for epiphytes and taxa with an annual life history, and were more likely to harbour sporophytic SI systems. Mapping the global distribution of georeferenced taxa by their family DR, we find evidence of regions dominated by taxa from lineages with high vs low SR. Discussion: These results are discussed within the context of the literature describing "depauperons" and the factors contributing to low and high biodiversity in angiosperm clades.

Phylogenetic endemism of the orchids of Megamexico reveals complementary areas for conservation.

Orchid diversity provides a unique opportunity to further our understanding of biotic and abiotic factors linked to patterns of richness, endemism, and phylogenetic endemism in many regions. However, orchid diversity is consistently threatened by illegal trade and habitat transformation. Here, we identified areas critical for orchid conservation in the biogeographic province of Megamexico. For this purpose, we evaluated orchid endemism, phylogenetic diversity, and phylogenetic endemism within Megamexico and characterized orchid life forms. Our results indicate that the majority of the regions with the highest estimates of endemism and phylogenetic endemism are in southern Mexico and northern Central America, mostly located on the Pacific side of Megamexico. Among the most important orchid lineages, several belong to epiphytic lineages such as Pleurothallidinae, Laeliinae and Oncidiinae. We also found that species from diverse and distantly related lineages converge in montane forests where suitable substrates for epiphytes abound. Furthermore, the southernmost areas of phylogenetic diversity and endemism of Megamexico are in unprotected areas. Thus, we conclude that the most critical areas for orchid conservation in Megamexico are located in southern Mexico and northern Central America. We recommend that these areas should be given priority by the Mexican system of natural protected areas as complementary conservation areas.

Differential aggregation of polystyrene and titanium dioxide nanoparticles under various salinity conditions and against multiple proteins types.

The interaction of nanoplastics (NPls) and engineered nanoparticles (ENPs) with organic matter and environmental pollutants is particularly important. Therefore, their behavior should be investigated under the different salinity conditions, mimicking rivers and coastal environments, to understand this phenomenon in those areas. In this work, we analyzed the elementary characteristics of polystyrene-PS (unmodified surface and modified with amino or carboxyl groups) and titanium dioxide-TiO2 nanoparticles. The effect of salinity on their colloidal properties was studied too. Also, the interaction with different types of proteins (bovine serum albumin-BSA and tilapia proteins), as well as the formation of the BSA corona and its effect on the colloidal stability of nanoparticles, were evaluated. The morphology and dispersion of sizes were more uniform in unmodified-surface PS-NPs (70.5 ± 13.7 nm) than in TiO2-NPs (131.2 ± 125.6 nm). Likewise, Rama spectroscopy allowed recognizing peaks associated with the PS phenyl group aromatic ring in unmodified-surface PS-NPs (621, 1002, 1582, and 1602 cm-1). For TiO2-NPs, the data suggest belonging to the tetragonal form, also known as rutile (445, 610 cm-1). The elevation of salinity dose-dependently decreased NP colloid stability, with more significant variation in the PS-NPs compared to TiO2-NPs. The organic matter is also involved in this phenomenon, differentially as a function of time compared to its absence (unmodified-surface PS-NPs 30 psu/TOC 5 mgL-1/24 h: 2876.6 ± 378.03 nm; unmodified-surface PS-NPs 30 psu/24 h: 2133 ± 49.57 nm). In general, the TiO2-NPs demonstrated greater affinity with all proteins tested (0.066 g/L). It was observed that morphology, size, and surface chemical modification intervene in a relevant way in the interaction of the nanoparticles with bovine serum albumin (unmodified-surface PS-NPs 298 K: 6.08E+02; 310 K: 6.63E+02; TiO2-NPs 298 K: 8.76E+02; 310 K: 1.05E+03 L mol-1) and tilapia tissues proteins (from blood, gills, liver, and brain). Their morphology and size also determined the protein corona formation and the NPs' agglomeration. These findings can provide references during knowledge transfer between NPls and ENPs.

Genomic and Morphological Differentiation of Spirit Producing Agave angustifolia Traditional Landraces Cultivated in Jalisco, Mexico.

Traditional agave spirits such as mezcal or tequila are produced all over Mexico using different species of Agave. Amongst them, A. angustifolia is the most popular given its agricultural extension. A. angustifolia is a wild species extensively distributed from North to Central America, and previous studies show that it is highly related to the tequila agave A. tequilana. In different regions of Mexico, A. angustifolia is cultivated under different types and levels of management, and although traditional producers identify several landraces, for the non-trained eye there are no perceivable differences. After interviews with producers from different localities in Jalisco, Mexico, we sampled A. angustifolia plants classified as different landraces, measured several morphological traits, and characterized their genetic differentiation and diversity at the genome-wide level. We included additional samples identified as A. tequilana and A. rhodacantha to evaluate their relationship with A. angustifolia. In contrast with previous studies, our pool of ca 20K high quality unlinked SNPs provided more information and helped us to distinguish different genetic groups that are congruent with the ethnobotanical landraces. We found no evidence to genetically delimitate A. tequilana, A. rhodacantha and A. angustifolia. Our large genome level dataset allows a better understanding of the genetic identity of important A. angustifolia traditional and autochthonous landraces.

High sensitivity-low cost detection of SARS-CoV-2 by two steps end point RT-PCR with agarose gel electrophoresis visualization.

More than one year since Coronavirus disease 2019 (COVID-19) pandemic outbreak, the gold standard technique for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection is still the RT-qPCR. This is a limitation to increase testing capacities, particularly at developing countries, as expensive reagents and equipment are required. We developed a two steps end point RT-PCR reaction with SARS-CoV-2 Nucleocapsid (N) gene and Ribonuclease P (RNase P) specific primers where viral amplicons were verified by agarose gel electrophoresis. We carried out a clinical performance and analytical sensitivity evaluation for this two-steps end point RT-PCR method with 242 nasopharyngeal samples using the CDC RT-qPCR protocol as a gold standard technique. With a specificity of 95.8%, a sensitivity of 95.1%, and a limit of detection of 20 viral RNA copies/uL, this two steps end point RT-PCR assay is an affordable and reliable method for SARS-CoV-2 detection. This protocol would allow to extend COVID-19 diagnosis to basic molecular biology laboratories with a potential positive impact in surveillance programs at developing countries.

Analytical and clinical comparison of Viasure (CerTest Biotec) and 2019-nCoV CDC (IDT) RT-qPCR kits for SARS-CoV2 diagnosis.

BACKGROUND: Several RT-qPCR kits are available for SARS-CoV-2 diagnosis, some of them with Emergency Use Authorization (EUA) by FDA, but most of them lacking of proper evaluation studies due to covid19 emergency. OBJECTIVE: We evaluated Viasure RT-qPCR kit (CerTest Biotec, Spain) for SARS-CoV-2 diagnosis using FDA EUA 2019-nCoV CDC kit (IDT, USA) as a gold standard. RESULTS: Although we found the lack of RNA quality control probe as the main limitation for the Viasure kit, the sensitivity was 91.9% and the specificity was 100%. The limit of detection (LOD) was 2000 copies/mL and 1000 copies/mL for Viasure and IDT kits, respectively. CONCLUSIONS: Viasure RT-qPCR kit is a reliable tool for SARS-CoV-2 diagnosis but improvement of an alternative RT-qPCR reaction for RNA extraction quality control as RNaseP is recommended.

Corrigendum to: "One health" inspired SARS-CoV-2 surveillance: The Galapagos Islands experience [One Health 11 (2020) 100185].

[This corrects the article DOI: 10.1016/j.onehlt.2020.100185.].

Seasonal effects and fine-scale population dynamics of Aedes taeniorhynchus, a major disease vector in the Galapagos Islands.

Characterization of the fine-scale population dynamics of the mosquito Aedes taeniorhynchus is needed to improve our understanding of its role as a disease vector in the Galapagos Islands. We used microsatellite data to assess the genetic structure of coastal and highland mosquito populations and patterns of gene flow between the two habitats through time on Santa Cruz Island. In addition, we assessed possible associations of mosquito abundance and genetic diversity with environmental variables. The coastal and highland mosquito populations were highly differentiated from each other all year round, with some gene flow detected only during periods of increased precipitation. The results support the hypothesis that selection arising from ecological differences between habitats is driving adaptation and divergence in A. taeniorhynchus, and maintaining long-term genetic differentiation of the populations against gene flow. The highland and lowland populations may constitute an example of incipient speciation in progress. Highland populations were characterized by lower observed heterozygosity and allelic richness, suggesting a founder effect and/or lower breeding site availability in the highlands. A lack of reduction in genetic diversity over time in highland populations suggests that they survive dry periods as dormant eggs. Association between mosquito abundance and precipitation was strong in the highlands, whereas tide height was the main factor affecting mosquito abundance on the coast. Our findings suggests differences in the infection dynamics of mosquito-borne parasites in the highlands compared to the coast, and a higher risk of mosquito-driven disease spread across these habitats during periods of increased precipitation.

"Sample pooling of RNA extracts to speed up SARS-CoV-2 diagnosis using CDC FDA EUA RT-qPCR kit".

BACKGROUND: The CDC protocol for SARS-CoV2 RT-PCR diagnosis (2019-nCoV CDC kit) is considered a gold standard worldwide; based on three different FAM probes (N1 and N2 for viral detection; RP for RNA extraction quality control), three reactions per sample are needed for SARS-CoV-2 diagnosis. RESULTS: We herein describe a sample pooling protocol: pooling 3 RNA extractions into a single PCR reaction; we tested this protocol with 114 specimens grouped in 38 pools and found no significant differences for N1 and N2 Ct values between pool and single sample PCR reaction. CONCLUSION: This pool of three protocol has a sensitivity of 100 % compared to the standard single sample protocol. For a typical 96-well plate, this pool assay allows 96 samples processing, speeding up diagnosis and reducing cost while maintaining clinical performance, particularly useful for SARS-CoV-2 diagnosis at developing countries.

Cotton-Tipped Plastic Swabs for SARS-CoV-2 RT-qPCR Diagnosis to Prevent Supply Shortages.

CDC and WHO guidelines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis only recommend synthetic fiber swabs for nasopharyngeal (NP) sampling. We show that cotton-tipped plastic swabs do not inhibit PCR and have equivalent performance to rayon swabs. Cotton-tipped plastic swabs are massively produced worldwide and would prevent swab supply shortages under the current high SARS-CoV-2 testing demands, particularly in developing countries.

Evaluation of nCoV-QS (MiCo BioMed) for RT-qPCR detection of SARS-CoV-2 from nasopharyngeal samples using CDC FDA EUA qPCR kit as a gold standard: An example of the need of validation studies.

BACKGROUND: Several qPCR kits are available for SARS-CoV-2 diagnosis, mostly lacking of evaluation due to covid19 emergency. OBJECTIVE: We evaluated nCoV-QS (MiCo BioMed) kit using CDC kit as gold standard. RESULTS: We found limitations for nCoV-QS: 1) lower sensitivity 2) lack of RNA quality control probe. CONCLUSIONS: Validation studies should be implemented for any SARS-CoV-2 RT-qPCR commercial kit to prevent unreliable diagnosis.

"One health" inspired SARS-CoV-2 surveillance: The Galapagos Islands experience.

The COVID-19 pandemic has spread worldwide since the outbreak in Wuhan (China) in December 2019, currently infecting over 25 million people and causing more than 800.000 deaths. In Ecuador, up to the 30th of August 2020, overall 113.648 confirmed cases and 6.555 deaths have been declared. Besides overloading of hospital, capacity for molecular diagnosis of SARS-CoV-2 by the Ministry of Public Health was quickly overwhelmed. In this context, emergency authorization for SARS-CoV-2 RT-qPCR diagnosis was granted to other institutions, like the "Agencia de Regulación y Control para la Bioseguridad y Cuarentena de Galápagos" (ABG), that implemented "LabGal" with support of One Health Research Group from "Universidad de Las Américas" (UDLA). The previous experience of ABG and the One Health Research Group in conducting massive surveillance of zoonotic diseases on livestock was crucial to the success on the control of COVID-19 outbreak at Galapagos Islands by the end of May 2020, when Latin American countries were leading the spread of the pandemic.