# Fusing _Fusarium_ Pathogens in the Era of Climate Change: A Conceptual Approach
## 1 Introduction  
Climate change has resulted in significant changes in weather patterns, precipitation distribution, and temperature fluctuations (FAO 2008). Extreme conditions caused by these changes bring about many unexpected and more frequent biotic and abiotic stresses [1; 2; 3; 4], in particular, novel combinations of stress severities [5]. At the same time the average annual variation in environmental factors might not change dramatically. To feed an increasing world population, total crop production needs to be significantly increased, but this becomes increasingly difficult due to lack of fertile arable land and more severe biotic and environmental stress conditions [6; 7; 8; 9; 10; 11].  
_Fusarium_ (_Hypocreales_, _Nectriaceae_) is one of the most renowned genera in the _Fungi_ kingdom. It includes, in a broad sense, a large number of morphologically and phylogenetically diverse fungi, commonly found as air-, soil-, or water-borne saprobic organisms, but also found in dead or livingplant material as endophytes or epiphytes [12]. Many _Fusarium_ spp. are effective plant pathogens or secondary invaders of worldwide concern. While numerous species are mycotoxicien and cause devastating human and animal diseases, they often occur isolated from their immunocompromised hosts [12]. Based on the perceived scientific and economic importance, _Fusarium_ spp. were recently included in the top 10 globally most important genera of plant pathogenic fungi [13]. This, in particular, reflects the economic importance of the diseases caused by _F. graminearum_[13].  
Fusarium head blight (FHB) is one of the most devastating fungal diseases worldwide. FHB is caused by a complex of up to 20 different co-existing _Fusarium_ species [14; 15; 16; 17; 18], substantially reducing cereal yield and quality and negatively impacting food safety. The outbreaks of the disease occur especially in years with warm and humid weather conditions resulting in yield losses of up to 75% [19]. Furthermore, the severity of _Fusarium_ infections is expected to further increase in future warmer climates [18]. In addition to yield loss the other major concern is the change in seed quality [17; 20]. Contamination of grain with mycotoxins leads to a quality loss for human consumption and poses difficulties in processing and feeding contaminated grain to animal species [14; 15; 16; 17; 21; 18]. The most frequently encountered _Fusarium_ mycotoxins in Europe are type B trichothecenes (TCTB). The family of TCTB mycotoxins include deoxynivalenol (DON) and its acetylated forms 15-acetyl-4-deoxynivalenol and 3-acetyl-4-deoxynivalenol (15-ADON and 3-ADON), and nivalenol (NIV) and its acetylated form fusarenone X (FX) [14; 15; 16; 19; 22]. TCTB mycotoxins have different acute and chronic effects on humans and animals and they were reported to be the primary cause of alimentary toxic aleukia, which has caused death of thousands of people in the USSR during the 1940s [23]. Currently, the biggest concern with TCTB mycotoxins does not result from short-term exposure to high mycotoxin concentrations, but from prolonged exposures that lead to chronic health effects [14; 15; 16; 17; 19; 23]. The refore, maximum allowable DON levels in food products have been established [[http://www.fao.org/3/5499e/y5499e07.htm](http://www.fao.org/3/5499e/y5499e07.htm)]([http://www.fao.org/3/5499e/y5499e07.htm](http://www.fao.org/3/5499e/y5499e07.htm)) and EC regulation EC856/2005 amended in July 2007/EC number 1126/2007) [23].