Borrelia Infections in Ageing Ticks: Relationship with Morphometric Age Ratio in Field-Collected Ixodes ricinus Nymphs

In Europe, Ixodes ricinus plays a major role as a vector of Borrelia burgdorferi sensu lato (s.l.) spirochaetes, the causative agents of Lyme borreliosis, among other pathogens. In unfed ticks, Borrelia spirochaetes experience prolonged nutrient restriction. However, only few studies exist with regard to Borrelia infections in unfed ticks of different physiological ages. Changing body dimensions of unfed ticks, due to the consumption of energy reserves, allow physiological age estimation. The present study investigated the relationship of morphometric age with Borrelia prevalence and spirochaete load in 1882 questing I. ricinus nymphs, collected at two different locations in northern Germany in 2020. In addition, Borrelia species composition was investigated by employing a reverse line blot (RLB) probe panel suitable for the detection of ten different B. burgdorferi s.l. species, as well as the relapsing-fever spirochaete B. miyamotoi. Overall, Borrelia prevalence was 25.8% (485/1882). Whilst there was no statistically significant difference in Borrelia prevalence between the different morphometric age groups, Borrelia infection intensity as determined by probe-based quantitative real-time PCR significantly declined with increasing morphometric age. Borrelia species differentiation by RLB was successful in 29.5% of positive ticks, and revealed B. afzelii as the dominating species (65.0% of the differentiated infections). Additionally, B. garinii, B. valaisiana, B. burgdorferi sensu stricto, B. spielmanii, and B. miyamotoi were detected.

Crioconservación de semillas de Cedrela odorata L.: germinación y establecimiento temprano en vivero.

La crioconservación de semillas representa una alternativa para la conservación a largo plazo de germoplasma forestal, sobre todo de especies tropicales intermedias o recalcitrantes, cuya viabilidad decae rápidamente bajo condiciones estándares de almacenamiento. Por ello, se evaluó en semillas de cedro rojo el impacto del congelamiento rápido en nitrógeno líquido (N2L) sobre la germinación sensu stricto y desarrollo temprano de la plántula. Para este fin, semillas deshidratadas o sin deshidratar se sometieron a pretratamientos de encapsulación/deshidratación en presencia de agentes osmoprotectores (LS, PVS2 y PVS3), previo a su congelación en N2L. Después de la descongelación a temperatura ambiente, se compararon la capacidad y velocidad de germinación de las semillas de los distintos tratamientos, así como el establecimiento, supervivencia y crecimiento de las plántulas después de cuatro meses en vivero. Los resultados muestran que las semillas de cedro rojo tienen la capacidad de sobrevivir el congelamiento rápido, aunque esto tuvo en general un efecto perjudicial durante las etapas de germinación y emergencia temprana, el cual fue menos severo en semillas sin encapsular. No obstante, los pretratamientos favorecieron la supervivencia de la plántula en vivero; el sistema radicular tuvo mayores afectaciones que la parte aérea en todos los tratamientos de congelación, lo cual incidió en una alta relación PSA/PSR. Se concluye que las semillas de Cedrela odorata sometidas al congelamiento rápido tienen el potencial de sobrevivir, germinar y producir plántulas para trasplante en vivero, aunque es necesario afinar el protocolo para optimizar la respuesta.

Long-Read Genome Assembly of Saccharomyces uvarum Strain CBS 7001

Here, we report a long-read genome assembly for Saccharomyces uvarum strain CBS 7001 based on PacBio whole-genome shotgun sequence data. Our assembly provides an improved reference genome for an important yeast in the Saccharomyces sensu stricto clade.

Host contributions to the force of Borrelia burgdorferi and Babesia microti transmission differ at edges of and within a small habitat patch

In the northeastern United States, the emergence of Lyme disease has been associated, in part, with the increase of small forest patches. Such disturbed habitat is exploited by generalist species, such as white-footed mice, which are considered the host with the greatest reservoir capacity for the agents of Lyme disease ( Borrelia burgdorferi sensu stricto) and human babesiosis ( Babesia microti ). Spatial risk analyses have identified edge habitat as particularly risky. Using a retrotransposon-based quantitative PCR assay for host bloodmeal remnant identification, we directly measured whether the hosts upon which vector ticks fed differed at the edge or within the contiguous small habitat patch. Questing nymphal deer ticks, Ixodes dammini , the northern clade of Ixodes scapularis , were collected from either the edge or within a thicket on Nantucket Island over 3 transmission seasons and tested for evidence of infection as well as bloodmeal hosts. Tick bloodmeal hosts significantly differed by site as well as by year. Mice and deer were identified most often (49.9%), but shrews, rabbits and birds were also common. Ticks from the edge fed on a greater diversity of hosts than those from the thicket. Surprisingly, mice were not strongly associated with either infection at either sampling site (OR<2 for all). Although shrews were not the most common host utilized by ticks, they were highly associated with both infections at both sites (OR= 4.5 and 7.9 B. burgdorferi and 7.9 and 19.0 B. microti , edge and thicket). We conclude that reservoir hosts may differ in their contributions to infecting ticks between edge and contiguous vegetated patches. Importance Habitat fragmentation is thought to be a main factor in the emergence of Lyme disease and other of the deer tick-transmitted infections. The patchwork of forest and edges promotes altered biodiversity, favoring the abundance of generalist rodents such as white footed mice, heretofore considered a key tick and reservoir host in the northeastern U.S. We used tick bloodmeal analyses to directly identify the hosts from which nymphal deer ticks became infected. We demonstrate that there is considerable microfocality in host contributions to the cohort of infected ticks and that shrews, although they fed fewer ticks than mice, disproportionately influenced the force of pathogen transmission in our site. The venue of transmission of certain deer tick-transmitted agents may comprise a habitat scale of 10 meters or fewer and depend on alternative small mammal hosts such as shrews.

Aggressiveness of Small-Spored Alternaria spp. and Their Sensitivity to Succinate Dehydrogenase Inhibitor Fungicides

Brown leaf spot of potato is caused by a number of small-spored Alternaria spp. Alternaria alternata sensu stricto, Alternaria arborescens, and Alternaria tenuissima have been reported with increasing frequency in commercial potato fields. Potato cultivars with resistance to small-spored Alternaria spp. have yet to be developed; therefore, the application of foliar fungicides is a primary management strategy. Greenhouse inoculation assays demonstrated that isolates of these three small-spored Alternaria spp. were pathogenic to potato. Significant differences in aggressiveness were observed across isolates; however, there was no trend in aggressiveness based on species. Significant fungicide by isolate interactions in in vitro fungicide sensitivity and significant differences between baseline and non-baseline isolates were observed in all three small-spored Alternaria spp. The ranges of in vitro sensitivity of A. alternata baseline isolates to boscalid (EC50 <0.010 to 0.89 µg/ml), fluopyram (<0.010 to 1.14 µg/ml) and solatenol (<0.010 to 1.14 µg/ml) were relatively wide when compared to adepidyn (<0.010 to 0.023 µg/ml). The baseline sensitivity of A. arborescens and A. tenuissima isolates to all four fungicides were less than 0.065 µg/ml. Between 10 and 21% of non-baseline A. alternata isolates fell outside the baseline range established for the four SDHI fungicides evaluated. In A. arborescens, 10 to 80% of non-baseline isolates had higher sensitivities than the baseline. A. tenuissima isolates fell outside the baseline for boscalid (55%), fluopyram (14%), and solatenol (14%) but none fell outside the baseline range for adepidyn. Evaluations of in vivo fungicide efficacy demonstrated that most isolates were equally controlled by the four SDHI fungicides. However, reduced boscalid efficacy was observed for four isolates (two each of A. arborescens and A. tenuissima) and reduced fluopyram control was observed in one A. alternata isolate. Results of these studies demonstrate that isolates of all three species could be contributing to the brown leaf spot pathogen complex and that monitoring both species diversity and fungicide sensitivity could be advantageous for the management of brown leaf spot in potatoes with SDHI fungicides.

Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) Infection Prevalence and Host Associations of Ticks Found on Peromyscus spp. in Maryland

Lyme disease, caused by Borrelia burgdorferi sensu stricto and most commonly transmitted by Ixodes scapularis Say (Ixodida: Ixodidae), is the most common tick-borne disease in Maryland. Because B. burgdorferi s.s. is maintained in enzootic cycles among wild mice (Peromyscus spp) and Ixodes spp ticks, differing patterns of parasitism of ticks on mice could impact the infection prevalence with B. burgdorferi. We determined the infection prevalence of Peromyscus spp as well as questing and partially engorged nymphal ticks collected at six sites on private land in five counties in Maryland from May to August 2020. Questing nymph infection prevalence (NIP) was 14%. We trapped 1258 mice and collected 554 ticks and 413 ear tissue samples. The prevalence of infested Peromyscus spp varied based on host age and sex, with older and male mice more likely to be infested. We detected a significant difference amongst the proportion of attached Ixodes and the location of trapping. Similarly, the prevalence of B. burgdorferi infected Peromyscus spp mice varied between locations (average mouse infection prevalence was 40%), with the highest prevalence in locations where Ixodes were the most commonly found ticks. The B. burgdorferi infection prevalence in partially engorged I. scapularis nymphs retrieved from Peromyscus spp was ~36% which lends further support to the host infection prevalence. Local differences in distribution of infected vectors and reservoirs are important factors to consider when planning interventions to reduce Lyme disease risk.

Were the First Trace Fossils Really Burrows or Could They Have Been Made by Sediment-Displacive Chemosymbiotic Organisms?

This review asks some hard questions about what the enigmatic graphoglyptid trace fossils are, documents some of their early fossil record from the Ediacaran-Cambrian transition and explores the idea that they may not have been fossils at all. Most researchers have considered the Graphoglyptida to have had a microbial-farming mode of life similar to that proposed for the fractal Ediacaran Rangeomorpha. This begs the question &ldquo;What are the Graphoglyptida if not the Rangeomorpha persevering&rdquo; and if so then &ldquo;What if&hellip;?&rdquo;. This provocative idea has at its roots some fundamental questions about how to distinguish burrows sensu-stricto from the external molds of endobenthic sediment displacive organisms.

REGARDING THE ACTIVITY OF A NATIONAL PARK DIRECTOR IN ENSURING THE SAFETY OF TOURISTS VISITING NATIONAL PARK AREAS

Purpose. The aim of the article is to analyse a national park director's legal position, roles, tasks and legal forms of operations in ensuring the safety of tourists visiting a national park. The objective of this analysis is also to determine whether the legal position, competencies and legal forms of activity at the disposal of the national park director are sufficient to ensure the safety of tourists visiting the national park. Method. The theoretical nature of this article determines the choice of research methods and their application. A dogmatic method (analytical and dogmatic) involving legal exegesis using linguistic and non-linguistic rules of legal interpretation is the predominant method applied in the article. Findings. The national park director’s legal status (including his/her position in the system of administering entities) is not clearly defined by the legislator and therefore, raises doubts. The legislature has not explicitly included this entity into the local authorities of consolidated and non-consolidated government administration. The legislator defines a national park director as a national park authority and a nature protection authority, directly indicating that this authority performs the tasks of a regional director aimed at nature protection within the national park area. The director of a national park may be classified as an administering entity, or on account of his/her tasks and powers, a public administration authority in a functional sense. However, it is misleading to treat national park directors as public administration authorities sensu stricto, i.e. the authorities who are part of the state machinery (authorities acting directly on behalf of the state or local self-governments), whose basic and, in principle, sole purpose is to perform public administration tasks (e.g. minister, province administrator, commune head). However, some authors consider national park directors to be public administration bodies sensu stricto [Makuch 2020, p. 527]. It has been confirmed in research that there is great diversity concerning tasks, powers and legal forms of operations at the disposal of a national park director, which can be used to ensure the safety of tourists visiting national parks. These are legal and factual activities of regulatory and non-regulatory nature. The tasks and competencies of national park directors include, first of all, protecting national park resources (environmental protection), which is the essence of their existence, and also providing access to national parks so as to ensure the safety of people who visit them. Research and conclusions limitations. The author focuses on analysis of the national legal framework. The origin of institutions and comparative legal analyses have been omitted. Practical implications. In the research, the current legal status is shown, and this can be considered the basis for further legislative work. Originality. To date, research on the national park directors' tasks, roles and legal forms of operation in ensuring the safety of tourists visiting national parks has been very scarce. Most of such issues are raised while discussing wider problems related to nature protection as well as tourism, and are not subject to in-depth examination [Wolski 2010, pp. 75-83]. In this context, it is worth noting that not only the national park directors' tasks and legal forms of activity require detailed analysis and evaluation, but their status in the state system and position in the system of administering entities as well. The current findings in this field are not sufficiently comprehensive and require further clarification. Type of paper. The article presents some theoretical concepts. It is a general overview article.

First Integrative Morphological and Genetic Characterization of Tremoctopus violaceus sensu stricto in the Mediterranean Sea

An integrative approach based on morphological and genetic analyses was undertaken for the first time to confirm the species identification of Mediterranean samples belonging to the genus Tremoctopus. Sequences of two mtDNA genes (cytochrome c oxidase subunit (COI) and 16S) were generated for the first time from Mediterranean samples. Both the similarity-based identifications and tree-based methods indicated that three females can be identified as Tremoctopus violaceus sensu stricto in agreement with their morphological classifications. All Mediterranean sequences clustered with the sequences of Tremoctopus violaceus from the Gulf of Mexico and were clearly differentiated from the sequences attributed to T. gracilis and T. robsoni. The chromatic pattern of the web and some features of gill filaments, arms formula, stylets, radulae, beaks, and stomach contents were given for all the samples; 105,758, 20,140, and 11,237 oocytes were estimated in the mature, immature, and developing samples, respectively. The presence of four spermatangia inside the cavity of the maturing female suggested the ability of this species to mate before reaching full maturity with more partners. Age investigation using beaks, performed for the first time in T. violaceus and within the genus gave results consistent with the different sizes and maturity conditions of the samples.

Abietane Diterpenes of the Genus Plectranthus Sensu Lato

Plectranthus (Lamiaceae), which—according to the latest systematic revision—includes three separate genera (Coleus, Plectranthus sensu stricto, and Equilabium), is a genus widely used in traditional medicine—mainly in the treatment of various ailments of the digestive tract, respiratory tract, and skin. Many species of Plectranthus s.l. have been shown to produce phenolic compounds and terpenes. Diterpenes, especially those of the abietane class, are the most studied group of secondary metabolites found in Plectranthus s.l., which is characterized by a significant structural diversity arising from the oxygenation and further rearrangement of the basic tricyclic abietane skeleton to a complete aromatization of the ring system. This review summarizes the known information on abietane diterpenes, showing their structures, sources, and biosynthesis. A classification of these compounds into nine groups, according to the arrangement of their ring C, is used. Royleanones, spirocoleons, and hydroquinones are the largest classes of abietane diterpenes, covering more than 70% of all the compounds reviewed.