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This paper describes the mycotoxins produced by fungi from the genera Fusarium, Penicillium, Aspergillus, Claviceps and other types of molds, their characteristics and importance. Mycotoxins are secondary fungi metabolites that serve as a defense mechanism in stressful conditions. Several hundred mycotoxins have been identified so far, and the most significant in terms of danger to human health and animals are aflatoxins, ochratoxin A, patulin, fumonisin, zearalenone and nivalenol/deoxynivalenol produced by toxigenic fungi from the genera Penicillium, Aspergillus, Claviceps, Stachybotris and Fusarium. Moisture and temperature are two factors that have a crucial influence on the development of the fungus and the synthesis of toxins. It is estimated that approximately 25% of agricultural crops are infected with fungi. Consequently, foods can also be contaminated with mycotoxins. By treating the stored grain with various chemicals, and in recent years, using environmentally friendly fungicides, the synthesis of mycotoxins is being prevented and the development of mycotoxicogenic fungi is being controlled. The mycotoxicosis can occur directly through the consumption of infected food, inhalation and skin contact, or indirectly through animals that eat contaminated feed. Mycotoxins have a pathological effect primarily on liver. Some mycotoxins also interfere with cellular protein synthesis, causing hypersensitivity and extreme immunodeficiency. Despite mycotoxins being resilient and remaining stable while undergoing chemical and thermal food processing, methods such as applying good hygiene and production practices from field to table can reduce their occurence., U ovom radu opisani su mikotoksini koji stvaraju gljivice iz rodova Fusarium, Penicillium, Aspergillus, Claviceps i drugih vrsta plijesni; njihove karakteristike i važnost. Mikotoksini su sekundarni metaboliti gljivica koji služe kao obrambeni mehanizam u stresnim uvjetima. Do sada je identificirano više stotina mikotoksina, a najznačajniji s obzirom na opasnost za ljudsko zdravlje i životinje su aflatoksini, ohratoksin A, patulin, fumonizin, zearalenon i nivalenol/deoksinivalenol koje stvaraju toksikogene gljivice iz rodova Penicillium, Aspergillus, Claviceps, Stachybotris i Fusarium. Vlaga i temperatura dva su faktora koji imaju krucijalni utjecaj na razvoj gljive i sintezu toksina. Procjenjuje se da je oko 25% poljoprivrednih usjeva zaraženo gljivama. Posljedično tome namirnice mogu također biti kontaminirane mikotoksinima. Tretiranjem uskladištenog zrna raznim kemikalijama, a zadnjih godina primjenom ekološki prihvatljivih fungicida, onemogućuje se sinteza mikotoksina i kontrolira se razvoj mikotoksikogenih gljiva. Do pojave mikotoksikoza može doći direktno konzumacijom zaražene hrane, inhalacijom i kontaktom putem kože ili indirektno konzumacijom mesa, mliječnih proizvoda i jaja životinja koje se hrane kontaminiranom krmom. Mikotoksini patološki prije svega djeluju na jetru. Neki mikotoksini također interferiraju sa sintezom staničnih bjelančevina uzrokujući preosjetljivost i ekstremnu imunodeficijenciju. Budući da je karakteristika mikotoksina da su kemijski i termički stabilni i da podnose procese prerade hrane, ipak postoje metode pomoću kojih se njihova pojavnost može smanjiti, pogotovo primjenom dobre higijenske i proizvodne prakse od polja do stola.

Pyrazoline derivatives exhibit a variety of biological activities, such as antifungal, antiviral, and antibacterial. Biological effects depend on the type of substituents and their position in the ring. [1] The aim of this study was to evaluate the inhibitory effects of fluorinated pyrazole aldehydes against plant pathogenic fungi (Fusarium oxysporum f. sp. lycopersici, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiourum). The compounds demonstrated moderate activity against phytopathogenic fungi. The highest efficiency has shown 2-chlorophenyl derivative (H9) against F. culmorum (46.75%). In order to determine the binding affinity and interactions of the most active compounds with three enzymes responsible for the fungal growth and the three plant cell wall-degrading enzymes, molecular docking was performed. In order to determine the possible mechanism of action of derivatives against pathogenic fungi, molecular docking study has been performed on three enzymes responsible for the fungal growth: demethylase (sterol 14α-demethylase (CYP51), PDB: 5EAH) ; chitinase (PDB: 4TXE) ; transferase (N-myristoyltransferase, PDB: 2P6G) ; and the three plant cell wall-degrading enzymes: endoglucanase I (PDB: 2OVW) ; proteinase K (PDB: 2PWB) ; pectinase (endopolygalacturonase, PDB: 1CZF). The future derivatives should be designed to be more effective against pathogenic fungi without negative effects on beneficial organisms, environment pollution, and human health

Maslina je iznimno važna kultura u mediteranskom dijelu Republike Hrvatske. Posljednjih godina provedena su istraživanja radi utvrđivanja uzročnika sušenja stabala maslina u Hrvatskoj i svijetu, u kojima su otkriveni novi patogeni do sada neprisutni na maslini. Najznačajnijim bolestima masline smatraju se: antraknoza, patula, paunovo oko, rak masline, sušenje stabala i plodova masline i verticilijsko venuće. Za suzbijanje uzročnika navedenih bolesti još se uvijek najčešće koriste fungicidi. Prekomjerna ili nekontrolirana primjena fungicida može dovesti do rezistentnosti patogena ili razvoja virulentnih sojeva, a negativno utječe i na okoliš. Za razliku od fungicida, biološka kontrola smatra se ekološki prihvatljivom metodom i sve se više koristi u suzbijanju štetnih organizama. Istraživanjem utjecaja različitih bioloških organizama, biljnih spojeva i ekstrakata na fitopatogene gljive masline potvrđen je njihov antifungalni učinak. Njihovo djelovanje na patogena proučavano je uglavnom u uvjetima in vitro. U ovome radu navedeni su mikroorganizmi i biološke komponente koje bi u budućnosti mogle biti sastavni dio bioloških preparata za kontrolu patogena masline.

Some of the phytopathogenic fungi from the Botryosphaeriaceae family can cause diseases on olive trees. The disease symptoms occur in the form of dieback and rotting of fruits, dieback of olive leaves and branches, the occurence of necrotic lesions and changes in the color of the bark. The presence of several species from this family has been identifed on the olive trees so far in Republic of Croatia. In 2021 and 2022, a field survey, and sampling of symptomatic olives was carried out on Istrian County territory. The main goals of the conducted research were: to determine the cause of symptomatic changes in olive trees in field research in Istria, and to carry out morphological and molecular identification of species of phytopathogenic fungi from the family Botryosphaeriaceae. The presence of the phytopathogenic fungi of the Botryosphaeriaceae family has been detected in 10 out of 25 locations visited. The largest number of samples was collected in the vicinity of Vodnjan and Rovinj, and phytopathogenic fungus were isolated from some of the most important olive varieties in Istria. Phytopathogenic fungi isolated from the infected plant material (15 isolates in total) have been identified on the basis of morphological and molecular characteristics. Molecular diagnostic was made using the polymerase chain reaction (PCR) method and multigenic analysis of the sequences ITS (internal transcribed spacer), TUB2 (betatubulin) and EF-1α (translation elongation factor 1-α). The research results indicated that the most prevalent species was the Botryosphaeria dothidea.

Olive (Olea europaea L.) is a very important crop grown in the Mediterranean part of Croatia. Olive branch and fruit dieback symptoms were observed in two olive orchards in Istria, Croatia. The samples from symptomatic trees were collected and brought to the laboratory for analysis. Based on their morphological characterization, isolated fungi were identified as Cytospora sp. Two representative isolates (one per orchard) were taken for molecular analysis, and based on DNA sequence data of the ITS and TUB gene regions, and phylogenetic analysis of the sequences, the isolates were identified as Cytospora pruinosa Défago. To determine pathogenicity, pathogenicity tests were conducted on detached olive branches and two-year-old olive trees in the greenhouse. This is the first report of C. pruinosa causing olive branch and fruit dieback in Croatia.

Coumarins and triazoles are two interesting groups of heterocyclic compounds, both exhibiting a wide range of biological activities. The joining of these two scaffolds into a hybrid compound with the improved activities has already been reported. [1] In this research, 11 new hybrid compounds were synthesized, utilizing a deep eutectic solvent as an environmentally sustainable method of organic synthesis. Compounds were obtained in good yields through a one-step reaction of coumarinyl hydrazides and various substituted isothiocyanates, without the use of catalysts. [2] Since many commercially available fungicides are based on triazole derivatives, antifungal activity of 1, 2, 4-triazolyl coumarins was evaluated in vitro on two pathogenic fungi, Fusarium oxysporum and Fusarium culmorum. The tested compounds moderately inhibited the mycelial growth of F. oxysporum (35.0-57.5%), but were mostly ineffective against F. culmorum. Compound 1b, as the most potent growth inhibitor, was further analyzed computationally. A molecular docking analysis was performed to evaluate the binding mode of compound 1b with sterol 14 α-demethylase, the target enzyme of triazole based fungicides

The aim of this study was to investigate in vitro the volatile effect of twelve essential oils on the growth of Rhizoctonia solani and Pyrenophora graminea mycelia. The essential oils were applied in a volume of 25 μl at temperatures of 15, 20, and 30 °C. The zone of inhibition was measured at 96 hours and 192 hours after inoculation. Anise and thyme oils had the strongest volatile effect on the growth of mycelia of R. solani and P. graminea, which were not affected by different incubation times and temperatures. Pine and sweet orange oils had the weakest volatile effect on the mycelial growth of R. solani and P. graminea.

During cultivation, wheat is exposed to several abiotic and/or biotic stress conditions that may adversely impact the wheat yield and quality. The impact of abiotic stress caused by nitrogen deficiency and biotic stress caused by phytopathogenic fungus Fusarium culmorum on biomarkers of oxidative stress in the flag leaf of nine winter wheat varieties (Ficko, U-1, Galloper, BC Mandica, BC Opsesija, Ingenio, Isengrain, Felix, and Bezostaya-1) was analyzed in this study. Hydrogen peroxide concentration and lipid peroxidation level were measured as indicators of oxidative stress, while the antioxidant response was determined by measuring the concentration of phenolic compounds and activities of antioxidant enzymes. Wheat variety and nitrogen treatment had a significant effect on all examined biomarkers of oxidative stress in the flag leaf, while the impact of Fusarium treatment was less pronounced. The most significant impact on the measured stress biomarkers had a low nitrogen level, which mainly increased hydrogen peroxide concentration and lipid peroxidation level and decreased activities of antioxidant enzymes in most varieties. The obtained results were discussed and compared with the previous study in which biochemical analyzes were performed on the wheat spike. There was no significant strong correlation between flag leaf and spike response in the measured parameters, which, in addition to the variety-specific response, also indicates a tissue-specific antioxidant response.

The nicotinamide derivates represent the promising candidate in the field of pesticides due to significant fungicidal activity, insecticidal activity, herbicidal activity, plant growth regulator activity and bactericidal activity. The series of nicotinamide-bromides with various alkyl chain lengths (from ethyl to octadecyl) were synthesized, and the toxicity of aqueous solutions towards Fusarium graminearum, Sclerotinia sclerotiorum, and Botrytis cinerea was examined. The obtained data were compared with DFT calculations results to understand the structural origin of fungicidal behavior and correlate it with the structural properties of investigated molecules. A significant correlation was established between the lipophilicity of the molecules (obtained from DFT calculations) and the growth rate of the examined phytopathogenic fungi. The results had suggested that Sclerotinia sclerotiorum is most sensitive to nicotinamide compounds exposure, while F. graminearum is most resistant to the change of lipophilicity of compounds. For all investigated compounds, the growth rate was decreased with the increase of carbon atoms in the side-chain until [C14Nic] [Br]. Further prolongation increased the growth rate of fungus, as it was noted for [C16Nic] [Br] and [C18Nic][Br]. This behavior was explained by the distinguished hydrophobic and hydrophilic surfaces in [C14Nic][Br] due to interactions between keto oxygen and bromide anion absent in the case of nicotinamides with a longer chain.

Kukci (insekti) stvaraju višestruke direktne ili indirektne štete u poljoprivrednoj proizvodnji što rezultira nižim prinosom i smanjenom kvalitetom proizvoda. Uz kemijske mjere zaštite od štetnih kukaca nastoje se pronaći odgovarajući alternativni načini suzbijanja koji su okolišno prihvatljiviji. Biološki načini zaštite poljoprivrednih kultura uz pomoć entomopatogenih gljiva (EPG) proučavaju se od davnina međutim dosta njih je još uvijek nedovoljno istraženo i malo se zna o načinu njihova djelovanja. Prirodna zaraza kukaca s EPG prisutna je i dokazana kod većine redova kukaca, a najčešća je kod: rilčara (Hemiptera), dvokrilaca (Diptera), kornjaša (Coleoptera), leptira (Lepidoptera), pravokrilaca (Orthoptera) i opnokrilaca (Hymenoptera). Neke vrste EPG mogu imati ograničen krug domaćina dok druge kao što su Bauveria bassiana i Metarhisium anisoplie, mogu zaraziti preko 700 vrsta kukaca. Primjena EPG kontinuirano raste, neki od razloga su da su oni bezbjedni za korisne organizme, ne postoji opasnost od zagađenja okoliša, smanjuje se mogućnost pojave rezistentnosti štetnika, dolazi do povećanja bioraznolikosti, kao i visoka učinkovitost uz mogućnost suzbijanja šetnika u svim razvojnim stadijima. Utvrđeno je da mnoge vrste roda Fusarium imaju entomopatogeno djelovanje, tj. posjeduju zadovoljavajuće karakteristike u kontroli štetnih kukaca u poljoprivrednoj proizvodnji. Zabilježena je visoka stopa smrtnosti, jaka sporulacija i brzo djelovanje. Primjenom EPG roda Fusarium u znanstvenim istraživanjima utvrđena je učinkovitost preko 90% na različitim vrstama kukaca. Vrste roda Fusarium pokazale su patogenost i moguću uporabu na kukce iz redova: Dyctioptera, Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, Orthoptera i Thysanoptera. Najviše entomopatogenih sojeva vrsta roda Fusarium utvrđeno je kod kompleksa vrsta: F. incarnatum-equiseti, F. fujikuroi, F. solani i F. oxysporum. Upravo zbog visoke učinkovitosti suzbijanja kukaca u svim razvojnim fazama, potrebno je provoditi daljnja istraživanja učinkovitosti roda Fusarium na štetne kukce.

Tijekom uzgoja na polju, pšenica je izložena mnogim negativnim abiotičkim i biotičkim stresnim uvjetima koji mogu negativno djelovati na prinos i kvalitetu. Nedostatak dušičnog gnojiva, kao abiotički stresni čimbenik, može uzrokovati pojavu oksidacijskog stresa u tkivu pšenice. Također, pojavu oksidacijskog stresa može inducirati iinfekcija pšenice fitopatogenim gljivama iz roda Fusarium. Cilj je ovog istraživanja ispitati utjecaj abiotičkog stresa (dvije različite gnojidbe dušikom) i biotičkog stresa (infekcija vrstom Fusarium culmorum) na oksidacijski status i antioksidacijski odgovor različitih sorti pšenice. Mjereni su sljedeći pokazatelji oksidacijskog stresa: razina lipidne peroksidacije, aktivnosti antioksidacijskih enzima (katalaze, askorbat- peroksidaze, glutation- reduktaze), te koncentracije ukupnih topljivih fenola i fotosintetskih pigmenata. Sorta pšenice, tretman dušikom i Fusarium tretman imali su značajan utjecaj na ispitivane pokazatelje oksidacijskog stresa. Najznačajniji utjecaj imala je niska razina dušika, koja je većinom djelovala na smanjenje aktivnosti antioksidacijskih enzima te na smanjenje koncentracije pigmenata. Pri niskoj razini dušika, Fusarium tretman je djelovao na povećanje aktivnosti antioksidacijskih enzima, dok je u uvjetima visoke razine dušika aktivnost enzima većinom bila smanjena.

Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic plant pathogen responsible for the reduction of the crop quality and yield. One of the most efficient ways to prevent and control diseases caused by S. sclerotiorum is the use of chemical fungicides. However, their use led to the accumulation of residual fungicides in the soil, water, and agricultural products, as well as the appearance of fungicide-resistant forms of this phytopathogen. Therefore, there is a need for new, environmentally friendly compounds that would prove effective against S. sclerotiorum. This study aimed to derive a Quantitative Structure- Activity Relationship (QSAR) for the antifungal activity of 18 quinazolinone derivatives. Antifungal test against S. sclerotiorum was carried out according to the method of Siber et al. Antifungal activities of tested compounds, expressed as % inhibition, were converted in the form of the logarithm values (log % inhibition). The optimized 3D strictures of quinazolinone derivatives were used for the descriptor calculation. Considering the limited number of compounds, splitting into test and training set was not performed. The multiple linear regression QSAR models were obtained with a genetic algorithm (GA) using QSARINS 2.2.4. (University of Insubria, Varese, Italy). The best QSAR model was generated with three DRAGON descriptors: Mv, Mor09e and R6e. The model satisfied the fitting and internal validation criteria, confirming its stability and robustness: R2 = 0.91 ; R2adj = 0.89 ; F = 45.17 ; ΔK = 0.12 ; CCCtr = 0.95 ; Q2loo = 0.85 ; R2-Q2loo = 0.06 ; CCCcv = 0.92 ; R2Yscr = 0.18 ; Q2Yscr = -0.43. Molecular descriptors in obtained QSAR model revealed that quinazolinones of higher molecular weight (Mv), higher contribution of 3D distribution of electronegativity at 8 Å (Mor09e), and enhanced interactions of electronegative atoms at a topological distance 6 (R6e), have lower antifungal effects.

Provedeno je in vitro istraživanje antifungalnog djelovanja devet vrsta eteričnih ulja (anis, bor, cimet kora, citronela, čajevac, čempres, eukaliptus, klinčić, lavanda) na zemljišne patogene Globisporangium ultimum i Globisporangium irregulare. Eterična ulja primijenjena su u količinama 5, 15 i 30 µL. Rezultati istraživanja pokazuju da biološka aktivnost eteričnih ulja ovisi o primijenjenoj količini ulja i gljivičnoj vrsti. Osam dana od inokulacije najjače antifungalno djelovanje u svim primijenjenim količinama na G. ultimum imala su ulja klinčića, anisa, cimeta kore i citronele, a na G. irregulare ulje klinčića. Najslabije djelovanje na obje pseudogljive i u svim količinama imala su ulja bora i čempresa