Fusarium species complex and mycotoxins in grain maize from maize hybrid trials and from grower’s fields

Abstract

Aims: To quantify and to compare the occurrence of Fusarium species in maize kernels and stalk pieces, to analyse mycotoxins in kernels and maize crop residues, to evaluate two approaches to obtain kernel samples and to compare two methods for mycotoxin analyses. Methods and Results: The occurrence of Fusarium species in maize kernels and stalk pieces from a three‐year maize hybrid trial and 12 kernel samples from grower’s fields was assessed. Nine to 16 different Fusarium species were detected in maize kernels and stalks. In kernels, F. graminearum, F. verticillioides and F. proliferatum were the most prevalent species whereas in stalks, they were F. equiseti, F. proliferatum and F. verticillioides. In 2006, 68% of the kernel samples exceeded the recommended limit for pig feed for deoxynivalenol (DON) and 42% for zearalenone (ZON), respectively. Similarly, 75% of the samples from grower’s fields exceeded the limits for DON and 50% for ZON. In maize crop residues, toxin concentrations ranged from 2·6 to 15·3 mg kg−1 for DON and from 0·7 to 7·4 mg kg−1 for ZON. Both approaches to obtain maize kernel samples were valid, and a strong correlation between mycotoxin analysis using ELISA and LC‐MS/MS was found. Conclusions: The contamination of maize kernels, stalk pieces and remaining crop residues with various mycotoxins could pose a risk not only to animal health but also to the environment. With the hand‐picked sample, the entire Fusarium complex can be estimated, whereas combine harvested samples are more representative for the mycotoxin contents in harvested goods. Significance and Impact of the Study: This is the first multi‐year study investigating mycotoxin contamination in maize kernels as well as in crop residues. The results indicate a high need to identify cropping factors influencing the infection of maize by Fusarium species to establish recommendations for growers.

Crops are a main driver for species diversity and the toxigenic potential ofFusarium isolates in maize ears in China

“…This change may reflect a regional difference or a chemotype/species shift in recent years. Similar results were reported from Switzerland, where both dimensional and temporal variation of Fusarium composition on maize was observed (Dorn et al, 2009(Dorn et al, , 2011. Temporal variation events were also reported on wheat (Waalwijk et al, 2003;Ward et al, 2008).…”

Isolation and characterization of Fusarium verticillioides from maize in eastern China

“…Fusarium graminearum was prevalent in Yunnan province (southern China) from 1992 to 1995 (Li and Huang 1998). Dorn et al (2009Dorn et al ( , 2011 found that the distributions of Fusarium species could not be explained by temperature alone; it was suggested that temperature may not be critical and that other, yet unknown, factors more strongly influence Fusarium prevalence. Dowd and Johnson (2010) working in America, and Goertz et al (2010) in Germany, suggested that local field effects may influence both Fusarium outbreaks and maize mycotoxin levels more than do weather conditions.…”

Fusarium oxysporum, F. proliferatum and F. redolens associated with basal rot of onion in Finland

“…In other countries this pathogen has been found to survive in fields for years, e.g. in corn crop remnants it has survived for at least 3 years (Dorn et al, 2011). However, the survival of F. proliferatum in onion crop remnants has not been studied, and it is not known how persistent this species is in the field soil in Finland.…”