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Apple is one of the most economically important fruit crops worldwide, and postharvest fungal diseases can cause significant losses during storage (Petreˇs et al. 2020). Apple fruits (cv. Fuji) with necrosis symptoms were collected during the fall of 2022 from an ultra-low-oxygen cold storage facility in Titel, Serbia. The fruits originated from the apple orchards in Titel (45°12947.10N, 20°15923.60E). The pathogens were isolated from collected fruit samples using standard phytopathological techniques. Fruits were surface-sterilized, rinsed with sterile water, and aseptically cut in half, and small fragments collected from the border of healthy and diseased tissue were placed on potato dextrose agar (PDA) medium in Petri dishes and incubated at 25 ± 1°C in the dark for 7 days. The obtained 11 isolates were identified to the genus level as Alternaria (incidence, 46%), Penicillium (36%), Fusarium (9%), and Stemphylium (9%) based on their morphological characteristics. Pathogenicity of all the isolates was confirmed on apple fruits of cultivars Fuji and Golden Delicious. The fruits were surface-sterilized, sprayed with 5 ml of conidial suspension (1 × 105 conidia/ml), and incubated at room temperature for 21 days. Symptoms developed on inoculated fruits were the same as symptoms observed on apple fruit samples collected from cold storage.

One of the main climate change-related variables limiting agricultural productivity that ultimately leads to food insecurity appears to be drought. With the use of a recently discovered nanopriming technology, seeds can endure various abiotic challenges. To improve seed quality and initial growth of 8-day-old field pea seedlings (cv. NS Junior) under optimal and artificial drought (PEG-induced) laboratory conditions, this study aimed to assess the efficacy of priming with three different nanomaterials: Nanoplant Ultra (Co, Mn, Cu, Fe, Zn, Mo, and Se), Nanoplant Ca-Si (Ca, Si, B, and Fe), and Nanoplant Sulfur (S). The findings indicate that nanopriming seed treatments have a positive impact on seed quality indicators, early plant growth, and drought resilience in field pea plants established in both optimal and drought-stressed conditions. Nevertheless, all treatments showed a positive effect, but their modes of action varied. Nanoplant Ultra proved to be the most effective under optimal conditions, whereas Nanoplant Ca-Si and Nanoplant Sulfur were the most efficient under drought stress. After a field evaluation, the examined comprehensive nanomaterials may be utilized as priming agents for pea seed priming to boost seed germination, initial plant growth, and crop productivity under various environmental conditions.

During 2017, yellowing of sugar beet leaves occurred in sugar beet fields in Serbia. Disease was visible on individual plants which had symptoms of intercostal yellowing, leaves were upright and brittle and in time this yellowing turned into necrosis. For the purpose of this research leaves with these symptoms were collected from 40 fields and analyzed using ELISA on the presence of Turnip Yellows Virus (Beet mild yellowing virus), Beet Mosaic Virus, Beet Necrotic Yellow Vein Virus and Beet yellows virus. Results proved occurrence of these viruses and were commented in regard to meteorological data which were favorable for vector activity.

Cercospora beticola is economically the most important sugar beet leaf disease primarily controlled by fungicide applications. However, other factors influence its incidence as well, some of which are the choice of cultivar and plant nutrition. These factors have been put together in field trial, which tested reaction of eight sugar beet genotypes (G1-G8) and 20 variants of NPK nutrition.

Vrste roda Colletotrichum, prouzrokovači gorke truleži jabuke, predstavljaju jedne od najznačajnijih prouzrokovača truleži plodova jabuke u skladištu. Zbog dominantne zastupljenosti u odnosu na druge vrste ovog roda posebno su značajne vrste C. acutatum i C. gloeosporioides. S obzirom da upotreba fungicida nakon berbe i tokom skladištenja nije dozvoljena zbog njihovih nepovoljnih ekotoksikoloških svojstava, a plodovi ostaju nezaštićeni tokom skladištenja, neophodno je definisanje alternativnih rešenja. Prethodna istraživanja su dokazala značajan antifungalni potencijal etarskih ulja i njihovih hidrolata (sporednih proizvoda koji se dobijaju pri proizvodnji etarskih ulja), te mogu predstavljati adekvatnu zamenu fungicidima. U ogledu je ispitan uticaj etarskih ulja čubra (Satureja hortensis), bosiljka (Ocimum basilicum), muskatne žalfije (Salvia sclarea) i divljeg origana (Origanum vulgare), kao i hidrolata etarskih ulja čubra, bosiljka i muskatne žalfije na izolate KA7 (C. acutatum) i MRMCD6 (C. gloeosporioides).

Vrste roda Pectobacterium su proteklih godina postale jedne od deset najproučavanijih fitopatogenih bakterija. Pažnju zavređuju zbog sve učestalije pojave novih vrsta, ekstremnoj adaptivnosti različitim domaćinima i uslovima životne sredine. Intenzivna trgovinska razmena dovodi do povećanja mogućnosti dospevanja novih vrsta na udaljena područja proizvodnje krompira, uzimajući u obzir da je glavni izvor inokuluma zaražen vegetativni materijal namenjen za sadnju. Štete uzrokovane vrstama Pectobacterium dosežu velike razmere, s obzirom na to da svoju aktivnost nastavljaju i po završetku vegetacije – prilikom transporta, prerade i u uslovima skladišta. Suzbijanje ovih patogena postaje ekstremno zahtevno uzimajući u obzir opšti nedostatak baktericida, te su mnogobrojni napori učinjeni sa ciljem iznalaženja načina suzbijanja prouzrokovača vlažne truleži krtola u uslovima skladišta. Mnoga istraživanja ukazuju na visoku efikasnost biljnih ekstrakata i etarskih ulja, kao moćnih agenasa zaštite. U cilju utvrđivanja efekata etarskih ulja (EU) bosiljka (Ocimum basilicum), čubra (Satureja hortensis), divljeg origana (Origanum vulgare), vreska (Calluna vulgaris) i timjana (Thymus vulgaris) na vrste P. carotovorum (Pc), P. brasiliense (Pb) i P. punjabense (Pp), sproveden je ogled in planta, na krtolama krompira sorte Lady Claire, jedne od najosetljivijih sorti na Pectobacterium spp.

Primena fungicida u suzbijanju zemljišnih patogena ne predstavlja efikasnu i ekonomski opravdanu meru. Takođe, oni mogu da naruše balans korisnih mikroorganizama u zemljištu, dok njihove rezidue utiču na zagađenje životne sredine. U nastojanju da se smanji upotreba sintetičkih fungicida, primena bioloških agenasa može imati važnu ulogu u „eco-frendly“ poljoprivrednim sistemima. Biološki agensi kao što su vrste iz rodova Bacillus i Trichoderma se najčešće upotrebljavaju u biološkoj borbi protiv zemljišnih patogena. Cilj ovog istraživanja je bio da se ispita antagonistički uticaj Bacillus sp. i Trichoderma spp. na izolate Macrophomina phaseolina (ŠR55(3)/09 i ŠR23/11) u in vitro uslovima. Za ispitivanje je korišten Bacillus sp., 74 koji je komercijalno dostupan kao mikrobiološko đubrivo pod nazivom Bacillomix® Original (Bacillomix Co., Srbija). Metodom inkorporacije komercijalne suspenzije mikrobiološkog đubriva u KDA hranljivu podlogu ispitane su koncentracije preparata od 1, 2, 5 i 10%. U cilju ispitivanja osetljivosti M. phaseolina prema Trichoderma spp. korišteno je 13 izolata koji su predhodno identifikovani kao Trichoderma harzianum. Test dvojne kulture (TDK) je korišten kako bi utvrdili antagonistički uticaj ispitivanih izolata.

In light of climate change, pedunculate oak (Q. robur L.) was marked as the most threatened European tree species. Pedunculate oak is particularly jeopardized by powdery mildew disease caused by Erysiphe alphitoides. We hypothesized that priming of this tree species with ectomycorrhizal fungi could mitigate biotic stress and produce bioprotective properties against the disease. In this study, we have compared oaks’ foliar physiological and biochemical responses upon infection with E. alphitoides in the presence and absence of ectomycorrhizal fungi (ECM). The main aim of this study was to inspect how ECM modulate an oak’s biochemical response to infection with E. alphitoides, particularly at the level of the accumulation of the main polyamines (putrescine, spermidine, and spermine), soluble osmolytes (proline and glycine betaine), and phenolics (total phenolic content, flavonoids, and condensed tannins). A polyamine quantification was performed after derivatization by using high-performance liquid chromatography (HLPC) coupled with fluorescent detection. Oak seedlings inoculated with ECM fungi exhibited significantly higher levels of putrescine, spermine, and proline compared to non-inoculated seedlings, indicating the priming properties of the ECM. E. alphitoides caused an increase in individual and total polyamine content and lipid peroxidation in oak leaves regardless of the effect of ECM, while causing a decrease in physiological and antioxidative parameters and water use efficiency (WUE). Common biochemical parameters may contribute to understanding the underpinning plant defense mechanisms in three-way interactions among plants and pathogenic and ectomycorrhizal fungi and can be used as reliable adaptability descriptors in the context of climate change.

Under conditions of intensive plant production and intensive international trade with plant material, coupled with climate changes, plant pathogens became one of the major limiting factors in food and feed production. Besides these extremely favorable conditions for reproduction and dissemination of plant pathogens, resistance development to available control tools and ecotoxicological properties of these tools show that plant pathogen control has never been more challenging. Development of alternative, eco-friendly control tools against phytopathogens, became a necessity of contemporary agriculture. Essential oils are mixtures of complex volatile compounds. They are synthesized through secondary metabolic pathways in many plant species. Essential oils are normally extracted by hydro-distillation or steam distillation of plant tissues. Hydrolates are co-products of the distillation formed in significantly higher quantities than the target substance. Hydrolate represents aromatic water containing approximately 0.1% essential oil compounds.

Soft rot and blackleg are common diseases of potato (Solanum tuberosum) in Serbia. Opportunistic pectinolytic plant pathogens in the genus Pectobacterium cause soft rot and wilt diseases by cell wall degradation. They cause major economic losses in potato crops worldwide and are among the top 10 plant pathogenic bacteria (Mansfield et al. 2012). Potato plants (‘VR808’) with symptoms of wilting, slow growth, stem blackening, and tuber softening were collected from a commercial field in Zobnatica, Serbia, in July 2019 and analyzed. All symptoms occurred in the same field, and ~5% of plants were symptomatic. Isolation was performed from 10 randomly chosen symptomatic plants and tubers. Plant tissue was surface disinfected, and 1-cm sections from the margins of lesions were macerated in sterile distilled water (SDW) for 25 min and streaked on nutrient agar. After 48 h of incubation at 26C, predominant shiny, cream-colored, round colonies were obtained from all samples. Three representative isolates (MMZKVR1, MMZCVR2, and MMZKVR3) from independent samples were selected randomly for biochemical and pathogenicity tests. Isolates were gram-negative, nonfluorescent facultative anaerobes exhibiting pectinolytic activity on potato tuber slices and hypersensitive response on tobacco leaves. They expressed catalase activity but did not express oxidase or acid phosphatase activity or produce indole.

Pripadnici roda Fusarium, kao prouzrokovači fuzariozne truleži ploda jabuke, pored gubitaka koje prouzrokuju u proizvodnji jabuke, mogu sintetisati mikotoksine što je dodatni aspekt njihovog štetnog delovanja koji se ogleda u kontaminaciji plodova jabuke i proizvoda koji se dobijaju njenom preradom. Vrsta Fusarium avenaceum je u periodu 2016 - 2020. godine bila dominantni prouzrokovač fuzariozne truleži uskladištenih plodova jabuke na teritoriji R. Srbije, dok se vrsta Fusarium graminearum javljala sporadično. Za obe vrste utvrđen je kapacitet za proizvodnju mikotoksina.

Aspergillus flavus is the main producer of aflatoxin B1, one of the most toxic contaminants of food and feed. With global warming, climate conditions have become favourable for aflatoxin contamination of agricultural products in several European countries, including Serbia. The infection of maize with A. flavus, and aflatoxin synthesis can be controlled and reduced by application of a biocontrol product based on non‐toxigenic strains of A. flavus. Biological control relies on competition between atoxigenic and toxigenic strains. This is the most commonly used biological control mechanism of aflatoxin contamination in maize in countries where aflatoxins pose a significant threat. Mytoolbox Af01, a native atoxigenic A. flavus strain, was obtained from maize grown in Serbia and used to produce a biocontrol product that was applied in irrigated and non‐irrigated Serbian fields during 2016 and 2017. The application of this biocontrol product reduced aflatoxin levels in maize kernels (51–83%). The biocontrol treatment had a highly significant effect of reducing total aflatoxin contamination by 73%. This study showed that aflatoxin contamination control in Serbian maize can be achieved through biological control methods using atoxigenic A. flavus strains.

Charcoal rot of sugar beet, caused by Macrophomina phaseolina in recent years has become a main concern for farmers in Serbia. Since control measures are mostly preventive with only partial effect, introduction of alternative measures, such as biological control based on augmentation of mycoparasites, represents the most promising approach. ITS region and tef gene sequence analysis of ten Trichoderma spp. isolates from sugar beet and soybean rhizosphere was done to confirm species identity. All isolates were confirmed to be Trichoderma harzianum.

Cercospora leaf spot caused by the fungus Cercospora beticola is the most significant foliar disease of sugar beet in Serbia. Measures to reduce damage of this disease are based on the use of tolerant varieties, crop rotation and fungicide application. Climate changes and the resistance of Cercospora beticolastrains to fungicides from the strobilurin group further complicate the fight against this disease. In extremely favourable years for the development of disease with high temperatures and precipitation during the summer months, growers in Serbia perform 4-8 fungicide treatments.

Sugar beet is susceptible to a number of root rot diseases, and they are regularly occurring in Serbia. Economically most important pathogens are Macrophomina phaseolina and Fusarium spp.. Macrophomina phaseolina is predominantly found in isolates from sugar beet, especially during dry and hot summers. For more than thirty years already, our team of researchers follows the occurrence and etiology of sugar beet root rot in Serbia. The aim of this experiment was to evaluate the effect of mineral nutrition on root rot in commercial sugar beet cultivars.

World potato production is affected by plant pathogenic bacteria, which significantly limit crop yield and quality in recent years. Bacteria belonging to Pectobacterium and Dickeya genera, causal agents of blackleg and tuber soft rot of potato, are considered as one of the most important pathogens that affect plant production worldwide. Main source of infection are latently infected seed tubers, which transmitted over long trade distances significantly increase disease incidence. Main identification tools for Pectobacterium and Dickeya species until recently were morphological and biochemical characterization methods, followed by pathogenicity tests. Due to phylogenetic heterogeneity of the soft rot and blackleg causing bacteria, identification and differentiation to species and subspecies level became increasingly difficult. Therefore, development of efficient and reliable identification methods is of high importance. Molecular and serological methods offer accurate, reliable and cost-effective differentiation of high specificity and reproducibility. This work aimed to review Pectobacterium i Dickeya species occurring on potato, with special highlight on available molecular identification techniques., Proizvodnja krompira u svetu značajno je ugrožena delovanjem fitopatogenih bakterija, te godišnji gubici prinosa poprimaju sve veće razmere. Među deset ekonomski najznačajnijih fitopatogenih bakterija koje smanjuju prinos i kvalitet poljoprivrednih kultura ističu se vrste rodova Pectobacterium i Dickeya - prouzrokovači crne truleži prizemnog dela stabla "crna noga" i vlažne truleži krtola krompira. Najznačajniji izvor infekcije su zaražene semenske krtole, te bakterije ovim putem lako dospevaju u nova područja. Identifikacija bakterija rodova Pectobacterium i Dickeya se do nedavno zasnivala na proučavanju morfoloških odlika bakterijskih kolonija uz upotpunjavanje testovima patogenosti i biohemijskim analizama. Zbog heterogenosti populacije patogena precizna identifikacija prouzrokovača vlažne truleži je dodatno otežana. S obzirom na potrebe za brzom i pouzdanom identifikacijom, u primenu su uvedene serološke i molekularne metode. Molekularne tehnike identifikacije, zbog svoje visoke specifičnosti, brzine izvođenja, pouzdanosti i ponovljivosti danas zauzimaju vodeće mesto u identifikaciji patogena. U radu su prikazane vrste rodova Pectobacterium i Dickeya koje se javljaju na krompiru, sa posebnim osvrtom na molekularne tehnike identifikacije.