# Mycotoxin Level in Winter Wheat Grain as Impacted by Nitrogen and Manganese Fertilisation
## 1 Introduction  
Of all the agrotechnical procedures performed in intensive wheat cultivation, fertilisation--which includes the application of both micro- and macronutrients--has the strongest impact on yield, its chemical composition and, as a consequence, its quality [1]. When not properly balanced, fertilisation can impair the soil's physicochemical characteristics and fertility [2]. Macro and micronutrient fertilisation is of great importance in boosting wheat resistance to infestation with pathogens that cause root, culm base, leaf and ear diseases [3]. Cereal fungal diseases decrease grain yield and impair its quality [4]. The loss caused by reducing the grain mass and the number of grains per ear can reach 10 to 40% [5]. Strong plant infestation reduces the assimilation area and photosynthesis intensity [6]. Cereals are susceptible to diseases caused by _Fusarium_ spp. fungi, and wheat is particularly susceptible to _Fusarium_ head blight [7]. Ear infestation by _Fusarium_ spp. can cause a loss in yield of up to 15-20%, and even 60% in extreme cases, with infested grain being of low quality [8]. The intensity of _Fusarium_ head blight depends largely on weather conditions [9]. According to [PERSON] et al. [10], environmental conditions influence the processes of infection and colonisation in various ways, as well as an abundance ofspecies of the genus Fusarium spp. Humidity determines the intensity of the disease, while precipitation determines inoculum levels [11]. Significant infestation of spikes by _Fusarium_ spp., including _F. graminearum, F. culmorum, F. Poae_, and _F. avenueum_, requires substantial moisture persisting for at least 24 h and temperatures exceeding 15 \({}^{\circ}\)C [12]. Factors influencing wheat infection with _Fusarium_ spp. may include the following: agricultural technology, forecrop, fertilisation and use of fungicides [8; 13]. Hazard of _Fusarium_ spp. occurrence in wheat also depends on the genetically determined variety resistance [14]. According to Spanic [15], infected seeds with _Fusarium_ spp. were smaller with lower 1000 kernel weight and had less endosperm, which resulted in increased protein content. Grain infestation with fungi of _Fusarium_ spp. results in the formation of secondary metabolites, such as mycotoxins. In Poland, these include mainly trichothecenes A and B (deoxymivalenol (DON), nivalenol and T2/HT-2 toxins), fumonisins and zearalenone (ZEA) [16]. Mycotoxins are significant cereal contaminants, generating economic losses in the fodder and food industry and having an adverse impact on human and animal health [17]. The presence and concentration of mycotoxins produced by fungi of _Fusarium_ spp. in wheat depend on multiple factors, e.g., toxicenic potential of a specific fungus species [18], weather conditions [4; 19], presence of competitive microflora [20], tolerance of the cultivar [21] and growth conditions [22]. The literature reports on the nitrogen impact on _Fusarium_ spp. occurrence and mycotoxin production are inconclusive. According to [PERSON] et al. [23], [PERSON] et al. [24] and [PERSON] et al. [25], infestation by _Fusarium_ spp. and mycotoxin production was not related to the amount of nitrogen supplied. A study conducted by [PERSON] et al. [26], and [PERSON] et al. [27] indicates a distinct impact of IN fertilisation on _Fusarium_ spp. occurrence and mycotoxin production. [PERSON] et al. [28] and [PERSON] et al. [29] found nitrogen fertilisation to have the potential to damage cellular wall structures in plants and adversely impact plant chemical composition, thereby making plants more susceptible to pathogen invasions. Nitrogen excess makes plants more luxviant and the stand denser, resulting in higher moisture content, which favours infections by _Fusarium_ and mycotoxin production [29]. Micronutrients are involved in physiological and biochemical mechanisms of defence against pathogens. Manganese participates in the synthesis of lignin, which constitutes a physical barrier against pathogen infiltration [30; 31].