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Raspberry leaf blotch emaravirus (RLBV) has become established in many Serbian raspberry orchards as the most prevalent virus of raspberries in the country. The aim of this study was to evaluate the impact of RLBV on the red raspberry 'Willamette' variety. A trial was conducted in four raspberry orchards located in Western Serbia. Fruits from RLBV-infected and uninfected canes were analyzed for fruit size (fruit length, width, height, shape, and weight), soluble solids content, pH, titratable acidity, total sugars, and total phenolic and anthocyanin contents. The results of the study confirmed that RLBV significantly decreases fruit size and weight (9.15-27.49%) of 'Willamette' fruits. Soluble solids content was higher in infected fruits (1.55-7.39%), but the increase was not significant. RLBV did not cause significant changes in titratable acidity of raspberry juice, pH or total sugars content. Total phenolic and anthocyanin contents were higher in fruits of RLBV-infected plants in two out of four locations.

Summary. Sixty-five samples of grapevine from commercial vineyards in the Rasina district of Serbia were tested for the presence of grapevine Pinot gris virus (GPGV), using the reverse transcription-polymerase chain reaction. Fourteen samples of the grapevine varieties ‘Red Globe’, ‘Victoria’ and ‘Preobraženje’ were infected with GPGV. All the infected plants showed symptoms of leaf chlorotic mottling, puckering, and deformation, stunting, and reduced yields. The coding regions of the movement and coat protein (MP/CP) and a region of the RNA-dependent RNA polymerase (RdRP) domains of eight virus isolates were sequenced. Phylogenetic analyses of these genom- ic regions showed high nucleotide similarity among the Serbian GPGV isolates. This study is the first to describe genetic diversity of GPGV isolates in Serbia. [ABSTRACT FROM AUTHOR]

Previously chemically characterized Juniperus communis essential oil (EO) and post-distillation waste (PDW) were tested for cytotoxicity and antimicrobial activity against food contaminants. Microdilution assay showed that PDW induced moderate antifungal (minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values, ranging between 0.118-0.900 mg mL-1), and an antibacterial effect against Listeria monocytogenes (MIC and minimum bactericidal concentration (MBC) were 0.39 and 0.74 mg mL-1, respectively). Combinations of EO/PDW with selected antibiotics induced synergistic antilisterial activity in the checkerboard assay. The MTT assay determined that cytotoxicity against colon cancer cells was high for the EO but negligible for PDW (IC50 values were 0.087-0.106 and 1.450-6.840 mg mL-1, respectively). The selectivity indices indicated high selectivity of PDW against tested fungi and L. monocytogenes. In the adhesion-inhibition assay, PDW reduced in vitro adhesion of L. monocytogenes to colon cells (29-62% of inhibition). In conclusion, PDW exhibited an antimicrobial effect against important food spoilage and poisoning fungi and L. monocytogenes, and also reduced in vitro adhesion of L. monocytogenes to colon cells. The results indicate that J. communis PDW could be considered as natural preservative against food spoilage and poisonous fungi, and as an adjuvant to conventional therapy of listeriosis. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172058 and Grant no. 173032]

The aim of this study was to determine the changes in chemical composition of fresh red raspberry 'Willamette' fruits caused by the presence of raspberry leaf blotch emaravirus (RLBV). In three experimental orchards of 'Willamette' raspberry, fruits were harvested from RLBV-free and RLBV-infected plants in 2019 and 2020. Fruits were collected at appropriate maturity stages and further analyzed in terms of total phenolics, total anthocyanins, and selected individual phenolics. In all three experimental orchards, the phenolic profiles of the infected and uninfected fruit samples were considerably different during both studied years. Nonetheless, the intensity of the modifications varied greatly depending on the location and harvest year. Statistical analysis revealed that the influence of RLBV infection on the studied features was undeniable, although the influences of weather conditions and soil composition outweighed the influence of RLBV. Taking into consideration all the experimental and statistical data, it can be concluded that RLBV had an impact on the phenolic profile of raspberry 'Willamette' fruits, while sensitivity to environmental conditions and soil composition is emphasized. [ABSTRACT FROM AUTHOR]

The objective of this study is to assess the suitability of vitrification cryo-plate (V cryo-plate) and dehydration cryo-plate (D cryo-plate) methods for the long-term conservation of eight autochthonous Prunus domestica L. genotypes originating from the Balkan Peninsula region. In vitro shoot tips were briefly pre-cultured for 1 day at 23 °C in the dark on a medium containing 0.3 M sucrose and then embedded in calcium alginate gel within the wells of the aluminum cryo-plates. In the V cryo-plate protocol, dehydration was carried out at room temperature using the following vitrification solutions: original plant vitrification solution 2 (PVS2) and 90% PVS2 solution (for 20 and 40 min) and plant vitrification solution 3 (PVS3) (for 60 and 80 min). In the D cryo-plate protocol, desiccation was performed for 2, 2.5, or 3 h over silica gel at 23 °C. The effect of different treatments was evaluated by monitoring the regrowth of both non-frozen and cryo-preserved explants. After cryo-preservation, five genotypes achieved regrowth rates over 40% in at least one of the applied protocols, while two genotypes showed regrowth rates of around 10%. A significant improvement in regrowth success for all genotypes using both cryo-plate methods was achieved by pre-culturing shoot tips for 7 days on a medium containing 0.5 M sucrose in complete darkness at 4 °C. Shoots regenerated from cryo-preserved explants were further monitored in vitro. By the third subculture, they had not only regained but had even exceeded the multiplication capacity (index of multiplication, length of axial, and lateral shoots) of shoots regenerated from dissection controls. Following multiplication, the cryo-preserved shoots were successfully rooted and rooting ability was assessed by monitoring the percentage of rooting, number and length of roots, and height of rooted plantlets. [ABSTRACT FROM AUTHOR]

Cymbopogon martinii is an aromatic crop cultivated for the production of its essential oil (EO) which has different applications. Bearing in mind that C. martinii EO (CMEO) has already been proved for high antibacterial potential the aim of this study was to formulate stable CMEO nanoemulsions, being capable to combat Enterococcus faecalis biofilm, especially within infected tooth's root canal. Ten emulsions with variable CMEO content (2.5–10 % v/v) and Tween 80 (T80, 2.5–15 % v/v) were formulated (designated as E CMEO:T80) and screened for volume-weighted mean diameter (D4,3) and stability, using dynamic light scattering measurements. Chemical composition of stable nanoemulsions was monitored by UV–VIS and FTIR, while their antibacterial activity was estimated in microdilution assay. Antibiofilm properties of selected nanoemulsions were tested in vitro (cristal violet assay) and ex vivo (within root canals of the extracted teeth). Results showed that formulations containing 10 % of T80 and CMEO volume ≤ 6 %, as well as those having constant 2.5 % of CMEO and variable T80 volume (≤ 10%), namely E 2.5:2.5 , E 2.5:5, E 2.5:7.5, E 2.5:10, E 4:10 , and E 6:10 , were stable and nanosized (D4,3 <100 nm). FTIR and UV–VIS analyses confirmed successful encapsulation of the CMEO by T80 and showed that nanoemulsification did not affect CMEO composition. Evaluation of antibacterial potential showed that the most efficient were E 6:10 , E 2.5:2.5 and E 4:10 (MIC values 0.37–1.97 mg mL−1). Analysis of dependency of determined MICs on mean diameter and CMEO volume showed that antibacterial potential increased with both parameters. E 6:10 , E 2.5:2.5 and E 4:10 also reduced in vitro biofilm (inhibitory range 17.6–58.4 %), as well as intracanal biofilm (reduction ~2Log CFU). Presented results suggest E 6:10, E 4:10 and E 2.5:2.5 as the good candidates for further research. [Display omitted] • Emulsions with different ratio of C. martini oil and Tween 80 were prepared. • Characterization of the nanoemulsions showed successful oil encapsulation. • Nanoemulsions E 6:10 , E 2.5:2.5 , E 4:10 proved high antibacterial effect. • Nanoemulsions E 6:10 , E 2.5:2.5 and E 4:10 reduced ex vivo intracanal biofilm. • Nanoemulsification improved antibiofilm potential of the C. martini oil. [ABSTRACT FROM AUTHOR]