Possible climate change impact on occurrence of Aspergillus flavus on spelt wheat in Serbia Jelena KRULJ * * University of Novi Sad, Institute of Food Technology, 21000 Novi Sad, Bulevar cara Lazara 1, Serbia 1
Relevance of the Thesis In the recent time, there is heightened interest in the use of spelt wheat due to its health benefits and suitability for organic farming. Occurrence of Aspergillus flavus and production of associated mycotoxins in cereals pose a great risk to human and animal health in terms of food safety. Aflatoxins, well-known mycotoxins produced by Aspergillus species, have been classified as human carcinogens (group 1). The wide spread occurrence of aflatoxins in many food stuffs is more frequent due to climate change. Ecological distribution of A. flavus on crops and higher levels of aflatoxins contamination are significantly associated with near-future climate conditions such as the increase of global temperatures and drought conditions. The present study focused on the presence of Aspergillus species on spelt grains after the harvest in 2017, with a special focus on A. flavus. A. flavus, A. fumigatus, A. nidulans, A. niger and A. ochraceus were Aspergillus species isolated from the spelt wheat grains harvested in 2017. The relatively high frequency and low incidence of A. flavus determined in tested spelt wheat samples can negatively impact on human health, animal productivity, and international trade. Most predictions indicate that climate change scenarios, with global warming, could affect more frequent occurrence of Aspergillus species and their toxins in cereals in temperate regions. 2
Average temperature ( C) Precipitation (mm) Main Results Recent literature data indicate the more frequent presence of different fungi on spelt grains, which is significant from yield reduction, grain quality and safety point of view The presence of genus Aspergillus on cereal grains varies depending on agroecological conditions in Serbia for the relevant year of examination. The weather conditions in 2017 in North Serbia for period of growing seasons (may-july) were characterised by moderate conditions with slightly higher temperatures and significant lower average precipitation compared to the perennial average (Figure 1). According to analyses carried out at the national level, the period from 1960 to 2012 is characterised by a mean annual temperature trend of 0.3 C per decade (RHMZ). Alternaria and Fusarium species occur commonly on wheat grain with high frequency and incidence. Hot and dry weather conditions were suitable for the more pronounced occurrence of Aspergillus species on cereals. A. flavus, A. fumigatus, A. nidulans, A. niger and A. ochraceus were Aspergillus species isolated from the spelt wheat grains harvested in 2017. The relatively high frequency and low incidence of A. flavus determined in tested spelt wheat samples can negatively impact on human health, animal productivity, and international trade. The risk of aflatoxin contamination assesses to have a chance of increasing in crops in the future, if climatic conditions will be suitable to the growth of A. flavus and production of associated mycotoxins. Depending on the scenario, it was predicted a temperature increase ranging from 3.2 to 4 C which can be expected by the end of the century as well as a precipitation deficit of 20% in cereal-growing areas of Serbia. Hot and dry weather conditions are favourable for infection of cereals with A. flavus, as well as for biosynthesis of aflatoxins. 30 25 20 15 10 5 0 2017 May June July 0 Average temperature Perennial average temperature Average precipitation Perennial average precipitation Figure 1: Average temperature and precipitation in growing seasons of 2017 in North Serbia Figure 2:Aspergillus species on spelt grains (DG 18, 25 C, 7 days) 80 60 40 20 3
Impact and Prospectum The findings of this study indicate the necessity for continuous monitoring of emergence of A. flavus on spelt wheat in the field and during storage and processing i.e. from the field to the consumer. Changes in climatic conditions may lead to changes in mycobiota and mycotoxins commonly present in European samples of small grains. Most predictions indicate that climate change scenarios, with global warming, could affect more frequent occurrence of Aspergillus species and their toxins in cereals in temperate regions. Pre-harvest prevention of food and feed contamination is probably the best and widely explored strategy to avoid future exposure of human populations to unacceptable aflatoxin levels. *Krulj, J., Đisalov, J., Bodroža-Solarov, M., Bočarov-Stančić, A., Markov, S., Mladenov, N. & Kojić, J. (2017). First Report of Aspergillus flavus on Organic Spelt Wheat in Serbia. Plant Disease, 101(6), 1045-1045 **Krulj, J., Đisalov, J., Bočarov-Stančić, A., Pezo, L., Kojić, J., Vidaković, A. & Solarov, M. B. (2018). Occurrence of aflatoxin B1 in Triticum species inoculated with Aspergillus flavus. World Mycotoxin Journal, 11(2), 1-12. 4
Thank You Get in Touch Jelena KRULJ Address: Bulevar cara Lazara 1, Novi Sad, Serbia E-mail: jelena.krulj@fins.uns.ac.rs Phone number: +38164/0016957