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Analysis of ˈCandidatus Phytoplasma Prunorumˈ Titer in the Tissues of Apricot Trees (Prunus Armeniaca L.) During the Year.
Full text linkThis study focused on monitoring ˈCa. P. prunorumˈ detection rate and titer over the course of the year in one-year-old (January-May) or annual shoots (June-December) of apricot trees. As an experimental material, 3 apricot selections (H990/95, H990/177 and H980/74) each represented by 3 trees of the same age grown in the same orchard were selected and analysed monthly. The real- time PCR assay was used for absolute quantification of ˈCa. P. prunorumˈ. The results showed, that phytoplasma was detectable in high rates (above 90 %) from August until December in annual shoots and from January to March and in May in one-year-old shoots. Lower detection rates were observed in April and in June and July, showing, that these months are not reliable for phytoplasma detection. Phytoplasma titer remained the same from January to May in one-year-old shoots. In annual shoots the lowest titers were observed in June, while in the rest of the year, the titers were significantly higher and not differing from the titers in one-year-old shoots collected from January to May. ˈCa. P. prunorumˈ quantification also showed, that H990/95 selection had significantly lower phytoplasma titer than the H990/177 and H980/74 selections. This was also supported by the detection rates and symptoms, where H990/95 selection was showing lower values of these parameters than the rest of the selections.O
The effect of nitrification inhibitor on the yield and quality of Triticum aestivum L. and Brassica napus L. – A long-term experiment
Full text linkPurpose: The nitrogen is a crucial element in crop production, which can be associated with the environmental loss and low agronomic nitrogen efficiency. The utilization of fertilizers with inhibitors represents an economical option by lowering the number of applications, lowering the dose of nitrogen and limiting the risk of environmental loss of N. Methods: The long-term effect of nitrogen fertilizer with nitrification inhibitors (alternative technology) in comparison with conventional fertilizers (prevalent technology) on yield and quality of winter wheat and oilseed rape cultivated in field conditions at two experimental localities was evaluated. Results: The long-term average yields of both crops were significantly higher after the alternative technology with the NI (+0.4 t/ha wheat grain, +0.3 t/ha rape seed) in comparison with prevalent technology. The effect of NI also resulted in significantly higher average protein content (13 %), protein production (0.98 t/ha) and gluten content (29.5 %) in wheat grain in comparison with prevalent technology without NI (12.8 %; 1.04 t/ha; 28.7 %). The oil content of oilseed rape did not differ significantly between the compared fertilizer technologies. The alternative technology with NI resulted in significantly highest production of oil (+0.1 t/ha) in comparison with prevalent technology. The economic evaluation of alternative technology with NI resulted in net profit in comparison with prevalent technology in every scenario. Conclusions: These long-term results are proving, that addition of NI to the conventional fertilizer applied in higher dose and less applications is more suitable choice compared to the classic split nitrogen fertilization.OA-hybri
Fish community of a heavily modified urban stretch of the River Svratka: Fish rescue transfer prior to the initiation of flood protection constructions
Full text linkHere, we present the results of a large-scale fish rescue prior to the building of flood protection structures along a stretch of the River Svratka running through Brno city centre (Moravia, Czech Republic). During this demanding and unique event, 5,861 fish, with a total weight of 1,951 kg, were caught and successfully transferred downstream. A total of 21 species of fish were recorded, of which two were protected species and two non-native to the Czech Republic. The dominant species caught (i.e. > 10%) were chub (Squalius cephalus), nase (Chondrostoma nasus), roach (Rutilus rutilus) and vimba bream (Vimba vimba), making up 85% of the catch. While this stretch of the Svratka supported a type-specific fish community dominated by rheophilic species, the occurrence of many species was supported through stocking by the Moravian Anglers Association. The length-frequency distribution of individual fish species suggests there has been a lack of recruitment over a relatively long period. This is most likely linked with hydropeaking from the Brno reservoir water power plant, with daily sharp fluctuations in flow in a river channel lacking shallow bankside areas and refuges with slow-flowing water preventing fish fry survival.O
Beyond meteorological data: Modelling tree growth with ERA5-Land
Full text linkForests are increasingly impacted by climate change, affecting tree growth and carbon sequestration. Tree-ring width, closely related to tree growth, is a key climate proxy, yet models describing ring width or growth often lack comprehensive environmental data. This study assesses ERA5-Land data for tree-ring width prediction compared to automatic weather station observations, emphasizing the value of extended and global climate data. We analyzed 723 site-averaged and detrended tree-ring chronologies from two broadleaved and two gymnosperm species across Europe, integrating them with ERA5-Land climate data, CO2 concentration, and a drought index (SPEI12). A subset was compared with weather station data. For modelling interannual variations of tree-ring width we used linear models to assess parameter importance. ERA5-Land and weather-station-based models performed similarly, maintaining stable correlations and consistent errors. Models based on meteorological data from weather stations highlighted SPEI12, sunshine duration, and temperature extremes, while ERA5-Land models emphasized SPEI12, dew-point temperature (humidity), and total precipitation. CO2 positively influenced the growth of gymnosperm species. ERA5-Land facilitated broader spatial analysis and incorporated additional factors like evaporation, snow cover, and soil moisture. Monthly assessments revealed the importance of parameters for each species. Our findings confirm that ERA5-Land is a reliable alternative for modeling tree growth, offering new insights into climate-vegetation interactions. The ready availability of underutilized parameters, such as air humidity, soil moisture and temperature, and runoff, enables their inclusion in future growth models. Using ERA5-Land can therefore deepen our understanding of forest responses to diverse environmental drivers on a global scale.OA-hybri
The proteomic code: Novel amino acid residue pairing models “encode” protein folding and protein-protein interactions
Full text linkRecent advances in protein 3D structure prediction using deep learning have focused on the importance of amino acid residue-residue connections (i.e., pairwise atomic contacts) for accuracy at the expense of mechanistic interpretability. Therefore, we decided to perform a series of analyses based on an alternative framework of residue-residue connections making primary use of the TOP2018 dataset. This framework of residue-residue connections is derived from amino acid residue pairing models both historic and new, all based on genetic principles complemented by relevant biophysical principles. Of these pairing models, three new models (named the GU, Transmuted and Shift pairing models) exhibit the highest observed-over-expected ratios and highest correlations in statistical analyses with various intra- and inter-chain datasets, in comparison to the remaining models. In addition, these new pairing models are universally frequent across different connection ranges, secondary structure connections, and protein sizes. Accordingly, following further statistical and other analyses described herein, we have come to a major conclusion that all three pairing models together could represent the basis of a universal proteomic code (second genetic code) sufficient, in and of itself, to "encode" for both protein folding mechanisms and protein-protein interactions.OA-hybri
Testing a conservation compromise: No evidence that public wolf hunting in Slovakia reduced livestock losses
Full text linkVariation in the legal status and management of wolves (Canis lupus) across EU Member States provides a good opportunity to test the effectiveness of different practices to reduce livestock losses. This opportunity for testing is particularly useful for lethal interventions, as they are among the most controversial actions within the large carnivore management toolbox. We aimed to test a conservation compromise adopted in Slovakia, based on a public wolf-hunting scheme and annual hunting quotas between 2014 and 2019, and partially justified to reduce livestock losses. We assessed whether this hunting scheme influenced livestock depredation levels (at the district level). Wolves in the area fed mainly on wild ungulates (98.9% of consumed biomass). While domestic sheep comprised only 0.5% of the diet, they were dominant among the reported livestock killed by wolves (91.1%). Using two different approaches, we did not observe a relationship between the number of killed wolves and livestock losses. Alternatively, a negative relationship between wild prey biomass and livestock losses was found. Since 2021, public wolf hunting has not been conducted in Slovakia, and there is no merit in the previous justification for this conservation compromise to reduce livestock losses.O
Effects of moisture content on the behaviour of Scots pine heartwood and sapwood under impact
Full text linkThe material properties of sapwood and heartwood vary within various wood species and even they can show significant differences within a single tree. Scots pine (Pinus sylvestris L.), a species that plays a crucial role in timber production for joinery and building construction applications, is among those that show a notable distinction between its heartwood and sapwood. To examine the influence of moisture content (MC) on the impact behaviour of the sapwood and heartwood of pine, we tested specimens with two distinct moisture levels: a low moisture content (LMC) group with 12% MC and a high moisture content (HMC) group with 45% MC. In our study, we investigated deflection, normal strain and force development of the specimens during the short period of an impact, and also calculated the impact bending strength (IBS) of samples, using an impact testing machine equipped with a high-speed camera and digital image correlation method. Our results indicate that the differences between sapwood and heartwood at LMC were insignificant in the case of maximum deflection and normal strain, thus there is no need for differentiation; however, these differences became more pronounced, and non-negligible, with an increase in MC. We also evaluated the IBS of both heartwood and sapwood and found that, at LMC, heartwood had greater impact bending strength than sapwood, making it a preferable choice as a material subjected to impact loadings. Conversely, at HMC, both heartwood and sapwood would be equally strong against impacts, indicating that pine green wood shows no sensitivity to the ratio of sapwood to heartwood in the tree.O
Engineered human H-chain ferritin with reversed charge of the internal cavity exhibits RNA-mediated spongelike effect for loading RNA/DNA-binding molecules
Full text linkFerritins are globular proteins with an internal cavity that enables the encapsulation of a plethora of low-mass compounds. Unfortunately, the overall negative surface charge of ferritin's internal cavity hampers efficient loading of negatively charged molecules. Therefore, we produced a genetically engineered human H-chain ferritin containing a cationic RKRK domain, reversing the natural net charge of the cavity to positive, thus allowing for efficient encapsulation of negatively charged siRNA. Due to the reversed, positive charge mediated by RKRK domains, the recombinant ferritin produced in E. coli inherently carries a load of bacterial RNA inside its cavity, turning the protein into an effective sponge possessing high affinity for DNA/RNA-binding substances that can be loaded with markedly higher efficiency compared to the wildtype protein. Using doxorubicin as payload, we show that due to its loading through the RNA sponge, doxorubicin is released in a sustained manner, with a cytotoxicity profile similar to the free drug. In summary, this is the first report demonstrating a ferritin/nucleic acid hybrid delivery vehicle with a broad spectrum of properties exploitable in various fields of biomedical applications.OA-hybri
Dothistroma septosporum and Dothistroma pini, the causal agents of Dothistroma needle blight, are infected by multiple viruses
Full text linkDothistroma septosporum and Dothistroma pini are severe foliar pathogens of conifers. They infect a broad spectrum of hosts (mainly Pinus spp.), causing chlorosis, defoliation of needles, and eventually the death of pine trees in extreme cases. Mycoviruses represent a novel and innovative avenue for controlling pathogens. To search for possible viruses hosted by Dothistroma spp. we screened a subset of isolates (20 strains of D. septosporum and one D. pini) originating from the Czech Republic, Slovenia, Italy, Austria and Ireland for viral dsRNA segments. Only five of them showed the presence of dsRNA segments. A total of 21 fungal isolates were prepared for total RNA extractions. RNA samples were pooled, and two separate RNA libraries were constructed for stranded total RNA sequencing. RNA-Seq data processing, pairwise sequence comparisons (PASC) and phylogenetic analyses revealed the presence of thirteen novel putative viruses with varying genome types: seven negative-sense single-stranded RNA viruses, including six bunya-like viruses and one new member of the order Mononegavirales; three positive-sense single-stranded RNA viruses, two of which are similar to those of the family Narnaviridae, while the genome of the third correspond to those of the family Gammaflexiviridae; and three double-stranded RNA viruses, comprising two novel members of the family Chrysoviridae and a potentially new species of gammapartitivirus. The results were confirmed with RT-PCR screening that the fungal pathogens hosted all the viruses and showed that particular fungal strains harbour multiple virus infections and that they are transmitted vertically. In this study, we described the narnavirus infecting D. pini. To our knowledge, this is the first virus discovered in D. pini.O
Establishing Young Vineyards according to the Simonit & Sirch Method
No full textSprávná praxe zakládání vinic hraje pro budoucnost vinohradnictví významnou roli. Správně založená struktura dřeva je schopna lépe odolávat extrémním změnám a především produkovat stabilní výnos. K lepšímu porozumění vnitřních procesů révy je důležité správně aplikovat zásady precizního řezu dle metody italských mistrů Simonit & Sirch.Proper vineyard establishment plays a significant role in the future of viticulture. A well-established wood structure is better able to withstand extreme changes and, most importantly, produce stable yields. To gain a better understanding of the internal processes of the grapevine, it is essential to correctly apply the principles of precise pruning according to the method of the Italian masters Simonit & Sirch.Published Versio