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Farkas, R.

Publications and source records attributed to Farkas, R..

6 recordsLinked to original sources

Experimental comparison of mowing and mulching on snail communities in wet meadows

The condition of wet meadows nowadays depends mainly on human activities; the biodiversity and productivity of these habitats can only be maintained by appropriate management methods. Mowing and grazing are well-known traditional methods, but a new method, regular mulching - the fragmentation of plant material and its deposition in the area - is also increasingly used. The ecological impact of traditional management is still not fully known, and we know almost nothing about the effects of mulching. To better understand the impact of these methods we directly compared their effects on snails, an invertebrate taxon common in these habitats and known as good bioindicators. We experimentally manipulated management methods on two wet meadows in Northern Hungary, Europe, and surveyed their snail communities immediately before and one year after treatments. Our results showed that mowing had a detectable negative effect on the snail communities. On the other hand, mulching did not alter their characteristics. Therefore, mulching may be a more desirable method for short-term interventions on wet meadows, whilst at the same time also preserving their biodiversity.

ecology↗

Apis mellifera filamentous virus from a honey bee gut microbiome survey in Hungary

In Hungary, as part of a nationwide, climatically balanced survey for a next-generation sequencing-based study of the honey bee (Apis mellifera) gut microbiome, repeated sampling was carried out during the honey production season (March and May 2019). Among other findings, the presence of Apis mellifera filamentous virus (AmFV) was detected in all samples, some at very high levels. AmFV-derived reads were more abundant in the March samples than in the May samples. In March, a higher abundance of AmFV-originated reads was identified in samples collected from warmer areas compared to those collected from cooler areas. A lower proportion of AmFV-derived reads were identified in samples collected in March from the wetter areas than those collected from the drier areas. AmFV-read abundance in samples collected in May showed no significant differences between groups based on either environmental temperature or precipitation. The AmFV abundance correlated negatively with Bartonella apihabitans, Bartonella choladocola, and positively with Frischella perrara, Gilliamella apicola, Gilliamella sp. ESL0443, Lactobacillus apis, Lactobacillus kullabergensis, Lactobacillus sp. IBH004. De novo metagenome assembly of four samples resulted in almost the complete AmFV genome. According to phylogenetic analysis based on DNA polymerase, the Hungarian strains are closest to the strain CH-05 isolated in Switzerland.

bioinformatics↗

Antimicrobial resistance gene lack in tick-borne pathogenic bacteria

Tick-borne infections, including those of bacterial origin, are significant public health issues. Antimicrobial resistance (AMR), which is one of the most pressing health challenges of our time, is driven by specific genetic determinants, primarily by the antimicrobial resistance genes (ARGs) of bacteria. In our work, we investigated the occurrence of ARGs in the genomes of tick-borne bacterial species that can cause human infections. For this purpose, we processed short/long reads of 1550 bacterial isolates of the genera Anaplasma (n=20), Bartonella (n=131), Borrelia (n=311), Coxiella (n=73), Ehrlichia (n=13), Francisella (n=959) and Rickettsia (n=43) generated by second/third generation sequencing that have been freely accessible at the NCBI SRA repository. From Francisella tularensis, 98.9% of the samples contained the FTU-1 gene, and 16.3% contained additional ARGs. Only 2.2% of isolates from other genera (Bartonella: 2, Coxiella: 8, Ehrlichia: 1, Rickettsia: 2) contained any ARG. We found that the odds of ARG occurrence in Coxiella samples were significantly higher in isolates related to farm animals than from other sources. Our results describe a lack in ARGs in these bacteria and suggest that antibiotic susceptibility testing might be considered before the treatment of tick-borne infections in farm animals.

genomics↗

A climatically representative analysis of Hungarian Ixodes ricinus tick bacteriome

BackgroundThe microbial communities of disease vectors may represent a key feature in several biological functions and thus deserve special attention in light of climate change and the consequent need to develop novel control strategies. Nevertheless, vector-borne microbial networks are still poorly understood. Assessing vectors microbial interactions and climatic dependencies may contribute to better-estimating pathogen transmission characteristics, public health risks and the urgency for control steps to be taken. MethodsIn a climatically representative country-wide survey, Ixodes ricinus ticks were collected from 17 locations in Hungary. Using shotgun metagenomic sequencing, the bacteriome composition was analyzed by investigating the relationship between the abundances of nymphs and females in various climatic environments. ResultsBacterial composition on the genus level revealed a significant difference between the samples from females and nymphs. Within the core bacteriome, females and nymphs showed significant variation in the following genera: Arsenophonus, Bacillus, Candidatus Midichloria, Rhodococcus, Sphingomonas, Staphylococcus, Wolbachia. Among females, according to temperature strata, the following were found differentiating: Curtobacterium, Pseudomonas, Sphingomonas. There was no genus with a significant difference in precipitation categories for females. In the nymphs, Curtobacterium showed significant variation between temperature and Bacillus and Curtobacterium for various precipitation levels. Based on the full sample set, Arsenophonus and Wolbachia correlated positively which we assumed to have occurred due to the presence of I. hookeri. ConclusionsThe composition of vector-borne bacteriome members showed significant alterations at sampling points with different climatic conditions and development stages of the tick hosts. Our findings not only pave the way towards understanding tick-borne bacterial networks and interdependencies but also shed light on the high potential for the presence of a possible biological tick control species, the tick parasitoid, Ixodiphagus hookeri based on related bacteriome patterns. The results of conscious tick microbiome assessment studies may contribute to precision tick control strategies of the future.

genomics↗

First detection of Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in Ixodes ricinus ticks (Acari: Ixodidae) from multiple locations of Hungary

The parasiotid wasp, Ixodiphagus hookeri (Hymenoptera: Encyrtidae) is the natural enemy of a wide range of hard and soft tick species. While these encyrtid wasps are supposed to be distributed worldwide, only few studies report about its actual appearance patterns around the globe. Within a shotgun sequencing based metagenome analysis, the occurrence of I. hookeri was screened at multiple Ixodes ricinus (Acari: Ixodidae) tick sampling points of Hungary, to contribute to the assessment of the appearance patterns of the parasitoid wasps in Central Europe. To our knowledge, the first report of the species in Hungary and the description of the southernmost I. hookeri associated geoposition in Central Europe took place within our study. I. hookeri infested I. ricinus nymphs were detected at five sampling points of Hungary. The results show that the exact distribution range of I. hookeri is still barely studied. At the same time, unprecedented public health issues being brought by climate change might require steps towards the exploitation of the tick biocontrol potential or ecological bioindicator role of the parasitoid wasp in the future.

genomics↗

Natural diversity of honey bee (Apis mellifera) gut bacteriome in various climatic and seasonal states

As pollinators and producers of numerous human consumed products, honey bees have great ecological, economic and health importance. The composition of their bacteriota, for which the available knowledge is limited, is essential for their bodys functioning. Based on our survey, we performed a metagenomic analysis of samples collected by repeated sampling. We used geolocations that represent the climatic types of the study area over two nutritionally extreme periods (March and May) of the collection season. In bacteriome composition, significant (p=0.002) difference was found between the samples from March and May. The samples bacteriome from March showed a significant (p=0.02) composition difference between cooler and the warmer regions. However, there were no significant bacteriome composition differences among the climatic classes of samples taken in May. Based on our results, one may conclude that the composition of healthy core bacteriome in honey bees varies depending on the climatic and seasonal conditions. This is likely due to climatic factors and vegetation states determining the availability and nutrient content of flowering plants. The results of our study prove that in order to gain a thorough understanding of a microbiomes natural diversity, we need to obtain the necessary information from extreme ranges within the hosts health state.

genomics↗