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The specifities of microorganisms life in soil
No full textDespite the importance, scale, and intensity of the nitrogen cycle processes in Earth’s biosphere, they are poorly understood, and the role of soil in the creation and absorption of nitrogen gases remains unclear, even though nitrogen largely determines the soil's ability to sustain productivity in terrestrial ecosystems. The state of terrestrial ecosystems and, of course, the stability of the biosphere directly depend on the content and rate of nitrogen transformation in soils, however, the investigation of nitrogen behavior in terrestrial ecosystems is only done in a fragmented manner. Therefore, the task of this review is to further clarify these phenomena and to focus the attention of younger generations of researchers in this field
Cryopreservation of highbush blueberry, strawberry, and saskatoon using V and D cryo‑plate methods and monitoring of multiplication ability of regenerated shoots
No full textThe purpose of this work was to apply V and D cryo-plate methods for cryopreservation of Vaccinium corymbosum ʻToroʼ, Fragaria × ananassa ʻCleryʼ, and Amelanchier alnifolia (Nutt.) M. Roem. and to monitor the multiplication capacity of shoots regenerated from cryopreserved explants. Shoot tips pre-cultured for 1 d at 23°C in the dark on medium containing 0.3 M sucrose were used as explants. Loading was performed in a solution containing 2 M glycerol and 0.8 M sucrose (30 min at room temperature). In the V cryo-plate, dehydration was carried out at room temperature (20 to 50 min) using the following plant vitrification solutions: original PVS2, 90% PVS2 solution, and PVS3. Regarding the D cryo-plate, dehydration was performed in closed glass containers over silica gel for 2, 2.5, or 3 h. In both protocols, rewarming was carried out in a 1.0 M sucrose solution (15 min at 25°C). Regenerated shoots were multiplied and multiplication parameters were monitored after the second subculture. Using the V cryo-plate method, the highest regrowth in highbush blueberry was obtained following 50-min treatment with all three VSs (61.7 to 80.9%). The D cryo-plate method was even more suitable with maximum regrowth of 89.4% achieved after 2.5 h of desiccation. For strawberry, 62.5% was the highest regrowth recorded using PVS3-based V cryo-plate method while 83.3% of regrowth was observed using D cryo-plate protocol. Regrowth of saskatoon reached a maximum of 50% after 50-min treatment with PVS3 while it did not exceed 40% in other treatments. By the second subculture, shoots regenerated from cryopreserved explants regained and even exceeded the multiplication capacity of shoots regenerated from non-cryopreserved explants. This study is the first to present the successful application of the V cryo-plate method in highbush blueberry, as well as the utilization of both V and D cryo-plate methods in saskatoon
Vplivi prevleke iz hitozana na kakovost plodov slive po skladiščenju
No full textThe effects of a chitosan coating on the quality and storability of 'Stanley' plum fruit were investigated. Plum fruits were treated with a 1.0 % w/v chitosan coating and stored at 1 ± 1 °C under 90–95% relative humidity for 28 days, and, subsequently, held at 24 °C for four days to evaluate shelf life. Some basic physical and chemical quality indices (weight loss, fruit firmness, soluble solids content, pH, content of total sugars, inverted sugars, sucrose and acids) were evaluated after storage, and after four days of shelf life. Furthermore, the occurrence of pathogens in treated and control fruit was monitored. Weight loss was pronounced after cold storage and it almost doubled during shelf life in both groups of plums, and the results obtained show that the chitosan coating could not prevent shrivelling. Although, the chitosan-coated fruits showed higher firmness after cold storage and during shelf life (2.51 kg/cm2, and 1.75 kg/cm2, respectively) than the control fruits (2.28 kg/cm2, and 1.66 kg/cm2, respectively), the observed differences were not statistically significant. There was also no significant difference in chemical composition between treated and control fruits. However, the percentage of fruit infected with Monilinia spp. at the end of cold storage was slightly lower in the chitosan-coated fruit (2.00%) than in the untreated fruit (3.33%). The effectiveness of chitosan coating in maintaining plum quality during storage therefore remains questionable.Raziskali smo vpliv prevleke iz hitozana na kakovost in sposobnost skladiščenja plodov sliv sorte 'Stanley'. Plodove sliv smo obdelali z 1,0 % m/v prevleko iz hitozana jih skladiščili pri 1 ± 1 °C pri 90–95 % relativni vlažnosti 28 dni, nato pa jih hranili pri 24 °C štiri dni, da bi ocenili rok uporabnosti. Nekatere osnovne fizikalno-kemijske kazalnike kakovosti (izguba mase, čvrstost plodov, vsebnost topne suhe snovi, pH, vsebnost skupnih sladkorjev, invertnih sladkorjev, saharoze in organskih kislin) smo izmerili po skladiščenju in po štirih dneh shranjevanja pri sobni temperaturi. Nadalje smo spremljali pojav patogenov pri tretiranih in kontrolnih plodovih. Izguba mase je bila po hladnem skladiščenju izrazita in se je med shranjevanjem pri sobni temperaturi pri obeh skupinah sliv skoraj podvojila, dobljeni rezultati pa kažejo, da obloga iz hitozana ni preprečila zgubanosti kožice. Čeprav so plodovi,prevlečeni s hitozanom, pokazali večjo trdoto po hladnem skladiščenju in med rokom trajanja (2,51 kg/cm2 oziroma 1,75 kg/cm2) kot kontrolni plodovi (2,28 kg/cm2 oziroma 1,66 kg/cm2), opažene razlike niso bile statistično značilne. Prav tako ni bilo pomembne razlike v kemični sestavi med tretiranimi in kontrolnimi plodovi. Vendar pa je odstotek plodov, okuženih z Monilinia spp. ob koncu skladiščenja nekoliko manjši pri plodovih, obloženih s hitozanom (2,00 %) kot pri netretiranih plodovih (3,33 %). Učinkovitost premaza s hitozanom pri ohranjanju kakovosti sliv med skladiščenjem ostaja torej vprašljiva
Volatile aging markers in Montenegrin plum spirits
No full textDepending on the preferences of the consumer, there are two categories of plum spirits that are consumed in Montenegro: colorless (they were not aged in wooden barrels) and colored (they were aged in wooden barrels). The aim of the work was to determine aging markers that are characteristic of plum spirits aged in wooden barrels.Volatile aging markers in plum spirits (9 samples aged in oak barrels and 3 sampled stored in glass vessels) originating from the north of Montenegro were analyzed. The GC-FID-MS method was used to determine the contents of 11 volatile components that are considered markers of distillate aging - 2 oak lactones and 9 other compounds, mainly volatile aromatic phenols. Among the investigated compounds, only eugenol was found in all plum spirit samples (unaged and aged). 4-Methylguaiacol, vanillin, syringaldehyde, coniferylaldehyde, sinapaldehyde, and syringaresinol were only found in aged plum spirits and can be used as markers of aging plum spirit in oak barrels. However, proposed aging markers were not found in all aged plum spirits, considering that producers in Montenegro use barrels of different volumes and different agedness, and the length of distillate aging varies from producer to producer
The effect of pollination variant and temperature on reproductive behaviour of some highbush blueberry (Vaccinium coyimbosum L.) cultivars
No full textPollination is a key factor in the production of highbush blueberry (Vaccinium corymbosum L.) to achieve a quantitatively and qualitatively satisfactory yield. Lower yields and small fruit without commercial value are correlated with poor pollination. This study was performed to investigate the flowering phenophase and pollen performance in vitro and in vivo of five cultivars (‘Duke’, ‘Reka’, ‘Bluecrop’, ‘Nui’ and ‘Ozarkblue’) that are commercially important in Serbia. Each cultivar was used as polleniser, while ‘Reka’, ‘Bluecrop’ and ‘Ozarkblue’ were also used as pollinated cultivars. Including the self- and open-pollination variants, a total of 18 combinations were investigated during the 3‑year study period. The studied blueberry cultivars flowered during the last third of April and the first half of May and, with the exception of ‘Ozarkblue’, had a satisfactory overlap in the flowering phenophase. There were genotype, year, and genotype × year interaction effects on pollen performance in vitro of the investigated blueberry cultivars. The pollination variant influenced pollen performance in vivo: The open-pollination variant was the most favourable in all tested cultivars, followed by the cross-pollination variant, with the exception of cultivar ‘Nui’ used as a polleniser, which showed worse results compared to the self-pollination variant. In addition, the pollinated cultivar impacted the pollen performance of pollenisers, while the impact of air temperature during the flowering phenophase can only be considered in the context of the responses for each male–female combination
Molecular characterization of apple mosaic virus isolates from apple and hazelnut in Serbia
No full textApple and hazelnut are important fruit crops for Serbian agriculture. Apple is traditionally one of the major fruits in the country, grown on more than 25,900 hectares, while the area under hazelnuts has rapidly increased in the last decade and reached 9,000 hectares. Both crops harbor numerous pathogens that challenge their production. Apple trees are affected by 20 viruses and virus-like agents, while only three viruses are known to infect hazelnuts. Apple mosaic virus (ApMV) belongs to the genus Ilarvirus, family Bromoviridae, and infects more than 65 plant species from the Rosaceae family. It poses a significant threat to the production of sensitive apple cultivars, reducing fruit yield, growth, and quality. Leaf symptoms include bright, pale-yellow chlorotic spots and mosaic patterns. ApMV is the most important virus infecting hazelnuts that can reduce growth and decrease yields. Characteristic symptoms on hazelnut leaves are chlorotic and yellow patterns, rings, and mosaics.
During a survey for virus diseases of apples and hazelnuts in Serbia from 2010 to 2022, we sampled and analyzed 150 apple and 70 hazelnut samples. The majority of samples were asymptomatic, but a small portion showed chlorotic and yellow patterns and mosaics, both on apple and hazelnut.
All samples were analyzed for ApMV presence using a double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with the reagents of BIOREBA AG, Switzerland. ELISA-positive samples were then tested by reverse transcription polymerase chain reaction (RT-PCR). RNA extraction was performed with the RNeasy mini kit (Qiagen, Germany). Two separate PCR reactions were performed using two specific primer pairs (92D9up/92E0re and 1F/1R) targeting fragments in the capsid protein gene and coat protein gene, respectively. PCR products were analyzed by 1.5% agarose gel electrophoresis and ethidium bromide staining. To further explore the diversity of the isolates, we sequenced partial genome fragments of 10 isolates.
ELISA tests confirmed ApMV presence in all 11 symptomatic apple and 6 hazelnut samples. ApMV was not detected in asymptomatic samples. PCR analysis with the 92D9up/92E0re primer pair yielded an expected 821 bp fragment only in apple samples. A primer pair 1F/1R amplified a 312-bp fragment in samples from hazelnut but not from apple. Seven isolates from apple and three from hazelnut were further sequenced (Macrogen Europe, the Netherlands).
This study confirmed a low incidence of ApMV in the analyzed apple and hazelnut samples, 7.3% and 8.5%, respectively. The ELISA test results coincided with the observed symptoms on the leaves. On the other hand, molecular PCR analysis was partially efficient and revealed significant divergence between isolates originating from apple and hazelnut. A clear difference was observed in the reliability and suitability of the primer pairs used for ApMV detection in these hosts. The presented results are of great importance for future recommendations for routine apple mosaic virus diagnostics and PCR utilization in phytosanitary certification
Antioxidant and antibacterial activities of Zizyphus jujuba L. leaf extracts
No full textThe aim of the present study was to investigate the biological activities of the extracts obtained from leaf of Ziziphus jujuba. To reach this purpose, total phenolic content (TPC), total flavonoid content (TFC), DPPH and ABTS radical scavenging activity, as well as antibacterial activity extracts were evaluated. The content of total phenols in leaf ranged from 22.71 to 28.69 mg GAE/g, the total content of flavonoids ranged from 5.15 mg RE/g to 8.25 mg RE/g depending on the applied extraction method. All extracts showed very high antioxidant activity. The ethanol extracts of Ziziphus jujuba leaf were screened for antibacterial activities against Salmonella typhimurium, Salmonella enteritidis, Listeria ivanovii, Listeria monocytogenes, Staphylococcus aureus and Pseudomonas aerogenes using microdilution method. Furthermore, the highest antibacterial activity was observed against Salmonella typhimurium and Salmonella enteritidis. The present results suggested the promising antioxidant and antibacterial properties of Ziziphus jujuba leaf extracts, which can be used in the fabrication of functional bioactive ingredients for different purpose
The effect of genotype-temperature interaction on pollen performance in the pistils of autochthonous ‘Dolga Šiška’ sweet cherry
No full textWithin the sweet cherry (Prunus avium L.), diversity is of crucial importance in the context of adaptation to changing environmental conditions. The cultivars origin, their wider geographical distribution, or spatial limitations in certain regions are related to their requirements for adequate conditions, which are especially visible through the reproductive process. This study was carried out to investigate pollen performance in vivo in the pistils of a sweet cherry landrace of Balkan origin (‘Dolga Šiška’) over a two-year period in the conditions of the prevailing Mediterranean climate of Ohrid Lake vicinity (Republic of North Macedonia). The pollenisers used are also of indigenous origin – ‘Ohridska Crna’ (Balkan region) and ‘Kordia’ (Czech Republic). Investigation was performed using the fluorescence microscopy method, on emasculated hand-pollinated flowers (cross-pollination) and non-emasculated open-pollinated flowers (open pollination), in the three terms of pistil fixation (3rd, 6th and 10th day from the full flowering date). In general, ‘Ohridska Crna’ showed a tendency of inducing higher number of pollen tubes (22.14, 11.78 and 6.20 pollen tubes in the upper, middle and lower parts of the style, respectively) in comparison with ‘Kordia’ (12.72, 6.62 and 2.92, respectively). This effect was particularly pronounced in the year with a lower flowering temperature. On the other hand, pollen tube kinetics showed the opposite tendency, being better with ‘Kordia’ as polleniser in warmer flowering season (7.69% of fertilization percentage and 3.60% fruit set, respectively), in comparison with ‘Ohridska Crna’ (penetration of pollen tubes into the nucellus and fruit set were not observed). Analysis of pollen performance in vivo parameters, pointed to the complex dependence on the polleniser genotype and temperature before and during the flowering, as well as the influence of pollination mode and pistilar genotype, which together contribute to the main factors’ interaction
Determination of the best pollenizers for sweet cherry cultivar ‘Canetova’
No full textSorta trešnje ʻCanetova’ izdvojena je selekcijom iz prirodne populacije na Poljoprivrednom fakultetu Univerziteta u Beogradu i priznata je 2015. godine. Zbog pozitivnih pomoloških i proizvodnih osobina, ova sorta se preporučuje za komercijalno gajenje u Republici Srbiji. Kako je ‘Canetova’, kao i većina sorti trešnje, samobesplodna, nameće se potreba izbora odgovarajućih oprašivača za njeno uspešno gajenje, što je bio i cilj ovog rada. Na osnovu identifikovanih S-haplotipova i rezultata višegodišnjih proučavanja fenofaze cvetanja, kao potencijalno dobri oprašivači za sortu ʻCanetova’ odabrane su sorte ʻBurlat’, ʻLapins’ i ʻRita’. Tokom dvogodišnjeg perioda (2023–2024) određena je in vitro klijavost polena navedenih potencijalnih oprašivača. Takođe, ispitana je efikasnost rasta polenovih cevčica in vivo u stubiću i plodniku tučka sorte ʻCanetova’ primenom metode fluorescentne mikroskopije, kao i finalno zametanje plodova u svim kombinacijama ukrštanja, uključujući varijantu slobodnog oprašivanja. Prosečne vrednosti klijavosti polena in vitro potencijalnih oprašivača kretale su se od 29,75% (ʻRita’) do 38,56% (ʻBurlat’). Najniža brojnost polenovih cevčica u svim posmatranim regionima tučka utvrđena je u varijanti slobodnog oprašivanja, dok je najveći broj polenovih cevčica u gornjoj (33,78) i srednjoj (19,98) trećini, kao i u bazi (10,94) stubića utvrđen u kombinaciji oprašivanja polenom sorte ʻBurlat’. Među ispitivanim oprašivačima, sorta ʻRita’ je indukovala najveći broj polenovih cevčica u plodniku sorte ʻCanetova’ (3,18). Polenove cevčice sorti ʻLapins’ i ʻRita’ odlikovale su se najbržim rastom i desetog dana nakon oprašivanja prodrle su u nucleus semenog zametka kod prosečno 56,62%, odnosno 53,17% tučkova sorte ʻCanetova’. Stoga su i najviše prosečne vrednosti finalnog zametanja plodova utvrđene u kombinacijama sa sortama ʻLapins’ i ʻRita’ kao oprašivačima (35,81 i 31,67%, po redosledu). Značajno niže vrednosti finalnog zametanja plodova sorte ʻCanetova’ dobijene su u varijanti slobodnog oprašivanja (24,04%), kao i u kombinaciji oprašivanja polenom sorte ʻBurlat’ (11,05%). Rezultati rada ukazuju da sorte ʻLapins’ i ʻRita’ predstavljaju adekvatne oprašivače za sortu ‘Canetova’.The sweet cherry cultivar ʻCanetova’ was selected from a natural population at the Faculty of Agriculture, University of Belgrade, and released in 2015. Due to its good pomological and production properties, this cultivar is recommended for commercial growing in the Republic of Serbia. Like most sweet cherry cultivars, ʻCanetova’ is self-incompatible, which imposes the need to choose suitable pollenizers for its successful cultivation. Based on the identified S-haplotypes and the results of many years of flowering phenophase investigations, the cultivars ʻBurlat’, ʻLapins’ and ʻRita’ were chosen as potentially good pollenizers for ʻCanetova’. During the two-year period (2023–2024), the in vitro pollen germination of the aforementioned pollenizers was determined. In addition, the efficiency of pollen tube growth in vivo in the style and ovary of the ʻCanetova’ pistils was monitored using fluorescence microscopy, and the final fruit set was observed in all crossing combinations, as well as in the open pollination variant. The average values of in vitro pollen germination of the studied potential pollenizers ranged from 29.75% (ʻRita’) to 38.56% (ʻBurlat’). The lowest number of pollen tubes in all observed regions of the pistil was determined in the open pollination variant, while the highest number of pollen tubes in the upper (33.78) and middle (19.98) thirds, as well as in the base (10.94) of the style, was determined in the crossing combination with ʻBurlat’. Among the assessed pollenizers, ʻRita’ induced the highest number of pollen tubes in the ovary of the cultivar ʻCanetova’ (3.18). The pollen tubes of the cultivars ʻLapins’ and ʻRita’ exhibited the fastest growth and penetrated the nucleus in an average of 56.62% and 53.17% of ʻCanetova’ pistils. Therefore, the highest average values of final fruit set were determined when using the cultivars ʻLapins’ and ʻRita’ as pollenizers (35.81% and 31.67%, respectively). Significantly lower values of fruit set were noted in the open pollination variant (24.04%) and in the crossing combination with ʻBurlat’ (11.05%). The obtained results show that the cultivars ʻLapins’ and ʻRita’ are the suitable pollenizers for the cultivar ʻCanetova’dr Ivana Glišić, član Programskog odbor
Improving the aroma of plum spirit obtained from small fruits of cv ‘Čačanska Rodna’
No full text‘Čačanska Rodna’ is very fruitful and has a tendency to overcrop. Therefore, for its successful growing, pruning is recommended as a mandatory measure. Regardless of the pruning intensity, a larger or smaller proportion of small fruits (<25 g) are always present on the tree. Due to their small size and inappropriate color, such fruits are not suitable for drying, fresh consumption and freezing. In Serbia, such small fruits are used for the production of plum spirit. The traditional method of plum spirit production includes crushing the fruits and spontaneous fermentation of the mash with stones, followed by double distillation, which results in overexpressed and often unpleasant stone-like aroma and, in the case of long and inadequate storage of the fermented mash, an acidic taste of plum spirit too. The aim of the study was to examine whether modifications of traditional plum spirit production method, which include a shorter storage time of the fermented mash, removal the stones before alcoholic fermentation, pulping of fruits and use of selected yeasts, can improve the smell and taste of plum spirit obtained from small fruits of cv ‘Čačanska Rodna’. The plum spirits obtained by six different processing methods, including the traditional one, differed significantly in terms of the contents of 21 out of 24 analyzed volatile compounds, as well as of sensory ratings. The plum spirit produced from the mash of crushed stoneless plums, spontaneously fermented and distilled immediately after finished alcoholic fermentation was evaluated with the highest sensory score, even higher than the plum spirits obtained by the most commonly used method in modern distilleries today (spirits from the pulped stoneless plums, fermented with selected yeasts and distilled immediately after finished fermentation). By choosing adequate processing method, excellent quality plum spirit can be obtained even from the small fruits of cv ‘Čačanska Rodna’