Colonisation of winter wheat grain byFusariumspp. and mycotoxin content as dependent on a wheat variety, crop rotation, a crop management system and weather conditions

Abstract

Field experiments were conducted during three consecutive growing seasons (2007/08, 2008/09 and 2009/10) with four winter wheat (Triticum aestivum L.) cultivars - 'Bogatka', 'Kris', 'Satyna' and 'Tonacja' - grown on fields with a three-field crop rotation (winter triticale, spring barley, winter wheat) and in a four-field crop rotation experiment (spring wheat, spring cereals, winter rapeseed, winter wheat). After the harvest, kernels were surface disinfected with 2% NaOCl and then analysed for the internal infection by different species of Fusarium. Fusaria were isolated on Czapek-Dox iprodione dichloran agar medium and identified on the basis of macro- and micro-morphology on potato dextrose agar and synthetic nutrient agar media. The total wheat grain infection by Fusarium depended mainly on relative humidity (RH) and a rainfall during the flowering stage. Intensive rainfall and high RH in 2009 and 2010 in the period meant the proportions of infected kernels by the fungi were much higher than those in 2008 (lack of precipitation during anthesis). Weather conditions during the post-anthesis period changed the species composition of Fusarium communities internally colonising winter wheat grain. The cultivars significantly varied in the proportion of infected kernels by Fusarium spp. The growing season and type of crop rotation had a distinct effect on species composition of Fusarium communities colonising the grain inside. A trend of a higher percentage of the colonised kernels by the fungi in the grain from the systems using more fertilisers and pesticides as well as the buried straw could be perceived. The most frequent species in the grain were F. avenaceum, F. tricinctum and F. poae in 2008, and F. avenaceum, F. graminearum, F. tricinctum and F. poae in 2009 and 2010. The contents of deoxynivalenol and zearalenon in the grain were correlated with the percentage of kernels colonised by F. graminearum and were the highest in 2009 in the grain from the four-field crop rotation. The content of T-2/HT-2 toxins was the highest in 2010 in grain from the three-field crop rotation and it was correlated with the isolation frequency of F. langsethiae.

Presence of Enniatins and Beauvericin in Romanian Wheat Samples: From Raw Material to Products for Direct Human Consumption

“…The same statistical conclusion was also reached by a research group from Slovenia, even if the contamination rate with AFLAs, OTA, fumonisins, DON, ZEA, HT-2, and T-2 toxins was higher for the organic cereal products [30]. In addition, different authors [31] declared that crop management system is the weakest factor influencing the internal colonization of winter wheat kernels by Fusarium fungi.…”

Airborne and Grain Dust Fungal Community Compositions Are Shaped Regionally by Plant Genotypes and Farming Practices

“…Weather conditions during the postanthesis period have previously been shown to affect the composition of Fusarium communities in winter wheat grain, and rainfall during the flowering stage is a major determinant of grain infection by Fusarium (12,51). Our results illustrate the role of climate on the overall taxonomic diversity of fungi.…”

“…Moreover, Alternaria, Cladosporium, and Epicoccum are well known for their allergenic properties (7). Although the drivers of wheat phytopathogen infection, such as climatic factors, wheat cultivar, and cropping history, have been intensively studied (12), little is known about the factors that shape the structure of entire fungal communities (e.g., pesticides) (13), and even less is known about fungal diversity in airborne dust generated during wheat harvesting. Thus, currently the homogeneity of the exposure of grain workers to fungal aerosols from one field to another during their work is difficult to estimate.…”

Influence of temperature, humidity duration and growth stage on the infection and mycotoxin production by Fusarium langsethiae and Fusarium poae in oats

“…In the present investigation, a significant effect of the humidity duration on mycotoxin production or amount of fungal DNA was not observed. This finding is in general accordance with previous findings that FP and FL are correlated with drier conditions rather than wet conditions (Xu et al ., ; Parikka et al ., ; Czaban et al ., ). However, testing the influence of water activity on FL growth in vitro , Medina & Magan () observed that no growth occurred at a water activity of 0.9 or below and that the optimum was >0.98.…”