Between 2008 and 2010, Agroscope Reckenholz- Tänikon ART conducted a first Swiss-wide monitoring of commercial grain maize samples. The aim was to determine the occurrence and impact of different ...Fusarium species in order to assess the potential risk of mycotoxin contamination. In addition, we evaluated the potential influence of different cropping factors in order to provide advice for growers on how to avoid high mycotoxin loads. 289 grain-maize samples from 14 cantons were analysed. Overall, 22 % of the grains were infected with Fusarium and 16 different species were identified. Fusarium graminearum, F. subglutinans, F. verticillioides and F. proliferatum were the most dominant species. In 2008 and 2010, 57 % and 70 % of the samples, respectively, exceeded the guidance value of 0,9 ppm deoxynivalenol (complementary and complete feedingstuffs for pigs). In 2009, 30 % of the samples exceeded this value. The levels of the other mycotoxins were substantially lower. Despite the extensive dataset, as of yet, only general recommendations can be defined with respect to influencing cropping factors that reduce the risk of mycotoxin contamination in grain maize.
In a 2-year investigation, harvest samples from Swiss growers' wheat fields were examined for Fusarium species incidence and data on cultivation techniques were collected. In addition, the content of ...the mycotoxin deoxynivalenol (DON) was analysed in three quarters of the samples. From a total of 248 samples originating from 16 cantons, three Fusarium species were dominant: F. graminearum, followed by F. poae and F. avenaceum. The average DON content, produced mainly by F. graminearum, was 1.0 ppm and thus barely below the maximum limit for unprocessed cereals (1.25 ppm). However, with the pre-crop maize and reduced or zero tillage, the average DON content was 3.2 ppm. The Fusarium incidence and the DON content differed between the two years, which could be explained by the prevailing weather conditions during and after wheat anthesis. The incidence of F. poae and F. avenaceum suggests that some wheat batches could contain the toxins nivalenol or moniliformin. By collecting data on cultivation techniques on a long-term basis, we aim to elucidate factors that influence infection by the most prevalent Fusarium species on wheat. This should allow us to develop means to reduce the risk of mycotoxin contamination.
In 2007 and 2008, Fusarium infestation and the content of deoxynivalenol (DON) in nine winter wheat varieties was investigated in three trials on two no-till farms. The trials formed part of a study ...on the feasibility of small-plot variety trials under no-till conditions. This paper mainly describes the Fusarium and mycotoxin situation. In Baggwil in 2007, the varieties Caphorn and Tapidor showed a higher incidence of head symptoms compared with other varieties. Pooled over all three trials, the resulting DON content was 10 to 15 times higher compared with the variety Arina. From the Fusarium species found on the harvested grain, F. graminearum and F. culmorum were the most prevalent species. In Baggwil in 2007, there was a surprisingly high proportion of F. culmorum, possibly dueto temporary ley as the preceding crop. The DON contents and frequencies of grain infestation with the two Fusarium species showed a strong correlation. Resistances from the list of recommended cereal varieties were confirmed by the grain infestation. According to the DON contents, however, individual varieties ought to be classified rather differently. Overall, the results demonstrate that no-till fields are highly appropriate for performing trials on Fusarium susceptibility of cereal varieties. With respect to the importance of fusaria as toxin producers, we recommend a modification of variety evaluation trials by using the criteria presented in this study including seed health test and DON analysis.
Fusarium species and mycotoxins in maize in Switzerland Dorn, B; Forrer, H.-R., Forschungsanstalt Agroscope Reckenholz-Taenikon ART, Zuerich (Switzerland); Schürch, S ...
Agrarforschung (Bern),
20/Jul , Volume:
16, Issue:
7
Journal Article
At several sites in Switzerland, the Fusarium incidence and the Fusarium species complex was assessed from maize kernels and stem pieces of commercially grown maize hybrids. The Fusarium incidence on ...kernels ranged from 0.4 % to 49.7 % and from 24.7 % to 83.8 % on stem pieces. Using the agar seed plate method, 16 different Fusarium species were isolated from kernels and 15 from stem pieces. Fusarium species prevalence differed between samples from the north and the south of the country, between kernel and stem pieces, between the different trial sites, as well as between the different years. The dominant species on kernels in the north were F. graminearum (33.0 %), F. verticillioides (28.9 %), F. subglutinans (10.6 %), F. proliferatum (7.0 %) and F. crookwellense (6.2 %). On stem pieces, the most frequently observed species were F. equiseti (36.0 %), F. verticillioides (20.1 %), F. graminearum (9.5 %), F. crookwellense (6.2 %) and F. sublutinans (6.2 %). In the south, the dominant species was F. verticillioides (57.1 %) und the fumonisin concentration in most of the samples exceeded the recommended maximum limits in feed of 5 mg kg-1.
As of yet, effective direct control of potato late blight in organic potato production requires the application of copper fungicides. However, with common dosage, copper is ecologically harmful. ...Hence, a considerable reduction or replacement of copper compounds in disease control is desirable. In the framework of the EU-project Blight-MOP comprising a systems approach to manage late blight in organic potato production without copper, 53 commercialised and experimental copper-free preparations were evaluated for their potential to control the disease by means of laboratory, greenhouse and field trials. Additionally, the potential to reduce copper fungicide input through optimised timing using the decision support system Bio-PhytoPRE developed at ART was assessed. In the laboratory, one-third of the copper-free preparations completely inhibited germination of sporangia and one-forth that of mycelial growth of Phytophthora infestans. In the greenhouse experiment one fifth of the copper-free preparations reduced foliar blight of tomato plants by at least 80 %. In microplot field trials, several copper-free preparations significantly reduced foliar blight of potatoes compared with the untreated control. However, the efficacy of the copper fungicides was never obtained. In small-plot field trials using practice-like application strategies, none of the copper-free preparations adequately controlled late blight sufficiently. The poor performance of the copper-free preparations under field conditions could be attributed to their low persistence and their lack of rain fastness compared to copper fungicides. In contrast to copper replacement, the strategy of using reduced application rates of copper fungicides according to the decision support system Bio-PhytoPRE proved to be successful.
The yield of winter wheat grown using three different farming systems (‘organic', ‘extensive IP' and ‘intensive IP') as well as the quality and health of its grains were compared in ...a long-term trial on Burgrain Farm in Alberswil (Canton of Lucerne, Switzerland). In the organic farming system, the land was ploughed, fertilized with farmyard manure, and weeds were controlled with a weeder. In ‘extensive IP' the wheat was cultivated using no-tillage; slurry fertilization was supplemented by ammonium nitrate and weeds were controlled with herbicides. In ‘intensive IP' the land was ploughed; 33 percent more nitrogen fertiliser, mainly mineral, was applied; growth regulators were used; weeds, diseases and pests were controlled by chemical plant protection products. There were no significant differences between the farming systems with regard to wheat grain infestation by the pathogen Microdochium nivale, the falling number and the hectolitre weight. In the no-tillage ‘extensive IP' system, however, infestation with Fusarium graminearum and the deoxynivalenol content of the wheat grain were three times that of the ‘organic' and ‘intensive IP' variants. The yield of the organic variant was about comparable to that of the ‘extensive IP' system but significantly lower than that of ‘intensive IP'. Despite the lower grain yield, ‘organic' was economically more viable than either IP system, thanks to higher producer prices and area contributions.
