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Fuzarijska palež klasa (FHB) je ozbiljna bolest pšenice (Triticum aestivum L.) koja uzrokuje smanjenje prinosa i kvalitetu zrna, a uzrokuju je plijesni roda Fusarium spp. Plijesni proizvode mikotoksine koji mogu biti štetni za ljude i životinje. Na infekciju biljke odgovaraju povećanom aktivnošću enzimatskog i neenzimatskog antioksidacijskog obrambenog sustava. Cilj ovoga rada bio je istražiti utjecaj roda Fusarium spp. na genotip ozime pšenice osjetljiv na FHB („Super Žitarka“) prateći aktivnost antioksidacijskih enzima, stupanj lipidne peroksidacije, koncentraciju vodikovog perkosida \[H_{2}O_{2}\] te ukupnu koncentraciju proteina nakon 2, 4, 7 i 14 dana tretmana Fusariumom. Tijekom cvjetanja uzorci su bili umjetno zaraženi suspenzijom spora Fusarium spp. i ostavljeni u uvjetima in vivo. U svim točkama uzorkovanja aktivnost askorbat peroksidaze (APX) i katalaze (CAT), kao i sadržaj proteina nisu pokazali značajne promjene nakon infekcije. Najveća aktivnost gvajakol peroksidaze (POD) bila je nakon 7 dana tretmana što upućuje da POD ima određenu ulogu u obrambenom odgovoru. Aktivnost polifenol oksidaze (PPO) pokazala je porast nakon 14 dana tretmana, što govori o kasnijem uključivanju PPO u odgovor na infekciju. Kasnije uključivanje antioksidativnih enzima u odgovor na Fusarium spp. karakterizira „Super Žitarku“ kao genotip osjetljiv na FHB. Ovo istraživanje napravljeno je u sklopu projekta financiranog od strane Hrvatske zaklade za znanost broj projekta: HRZZ-UIP-2014-9188. Fusarium head blight (FHB) caused by fungi Fusarium spp., is a serious wheat (Triticum aestivum L.) disease that can reduce yield and quality of the grain. Fungi produces mycotoxins that can be harmful to humans and animals. As a result of infection, plants activate an antioxidative enzymatic and nonenzymatic defence systems. The aim of this work was to investigate the effect of Fusarium spp. in FHB susceptible genotype („Super Žitarka“) by measuring the activity of antioxidative enzymes, level of lipid peroxidation, hydrogen peroxide \[H_{2}O_{2}\] concentration and protein content after 2, 4, 7 and 14 days of treatment. During the flowering stage, ears were inoculated by the spore suspension of Fusarium spp. and left under in vivo conditions. In all sampling points the catalase (CAT) and ascorbat peroxidise (APX) activity and protein content did not show showed significantly changes after Fusarium attack. The highest guaiacol peroxidise (POD) activity was noticed after 7 days of treatment indicating that POD had a role in defence response. On the other hand, polyphenol oxidase (PPO) activity showed induction after 14 days of treatment suggesting that PPO is included in delay response to Fusarium stress. The later involvement of antioxidative enzyme in stress response caused by Fusarium characterised “Super Žitarka” as FHB sensitive genotype. This research was carried out as part of a project funded by the Croatian Science Foundation project number: grant number HRZZ-UIP-2014-9188.

Proceedings contains articles presented at Conference divided into sections: open lecture (1), chemical analysis and synthesis (3), chemical and biochemical engineering (8), food technology and biotechnology (8), medical chemistry and pharmacy (3), environmental protection (11) and meeting of young chemists (2).

Fusarium head blight (FHB) caused by fungi Fusarium spp., is a serious wheat (Triticum aestivum L.) disease that can reduce yield and quality of the grain. Fungi produces mycotoxins that can be harmful to humans and animals. Plants provide ROS-scavening mechanisms that include both antioxidative enzymatic and nonenzymatic systems. Enhanced activities of ROS antioxidative enzymes can be a great indicator of genotype susceptibility under pathogen infestation. The aim of this work was to investigate the effect of Fusarium spp. in three wheat genotypes (‘Super Žitarka’, ‘Apache’ and ‘Lucija’) through activity of antioxidative enzymes, level of lipid peroxidation, H\(_{2}\)O\(_{2}\) concentration and protein content. At the anthesis, ears were inoculated by the suspension of Fusarium spp. and left under in vivo conditions. After 7 days of treatment in all wheat genotypes, Fusarium did not cause notable changes in catalase (CAT) activity. Treated ears of ‘Super Žitarka’ showed inhibition of APX activity. At the same time in ‘Lucija’ pathogen induced remarkably increase in activity of guaiacol peroxidase (POD) and polyphenol oxidase (PPO), decreased H\(_{2}\)O\(_{2}\) concentration, decline in malonedialdehyde (MDA) content and lower protein content. The variances in antioxidative response and protein content imply genetic variability of wheat genotypes, which can cause differences in Fusarium spp. susceptibility.

Fusarium head blight (FHB) caused by fungi Fusarium spp., is a serious wheat (Triticum aestivum L.) disease which can reduce yield and quality of the grain. Fungi produces mycotoxins which can be harmful to humans and animals. Plants exhibit a wide variety of defense strategies against pathogen attack such as hypersensitive response (HR), also called plant cell death, which has the aim to localize pathogen dissemination by overproduction of H2O2. In the initial stage of pathogen infection, plant produces excessive concentration of reactive oxygen species (ROS), like H2O2, superoxide (O2.-) and hydroxyl (OH.) radicals to protect themselves from attack. ROS accumulation can seriously endanger integrity of cell membranes throught lipid peroxidation or inhibit protein synthesis. Plants provide a ROS-scavening mechanisms which include both antioxidant enzymatic and nonenzymatic systems. Enhanced activities of ROS antioxidant enzymes can be a great indicator of genotype susceptibility under pathogen infestation. In wheat, Fusarium spp. induces activation of antioxidant enzymes like guaiacol peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD). In order to investigate the response of wheat genotypes and to determine antioxidant properties of FHB resistant wheat cultivars compared to susceptible one under Fusarium spp. infection, the inoculation of Fusarium macroconidia will be performed under field conditions. In a few occasions after inoculation, in plant tissue we will determine the activities of POD, CAT, APX and SOD. Furthermore, we will check the level of lipid peroxidation to detect possible degradation of cell membranes.