Bartok T.,Fumizol Ltd |
Bartok T.,University of Szeged |
Szecsi A.,Hungarian Academy of Sciences |
Juhasz K.,Debrecen University |
And 2 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2013
Following the earlier detection of six new esterified fumonisin B1 (EFB1) isomers containing three acyl groups in a Fusarium verticillioides-inoculated rice culture, it was assumed that linoleic, palmitic or oleic acid esterifies one of the free OH groups on the fumonisin backbone. On the basis of the results of our recent investigations we now propose that these EFB1 isomers are actually 3-O- and 5-O-acyl derivatives of FB1 (3-O-linoleoyl-FB1, 5-O-linoleoyl-FB1, 3-O-palmitoyl-FB1, 5-O-palmitoyl-FB1, 3-O-oleoyl-FB1 and 5-O-oleoyl-FB1). A F. verticillioides strain was identified that produced not only O-acyl-FB1 isomers, but also low amounts of three N-acyl derivatives (N-linoleoyl-FB1, N-palmitoyl-FB1 and N-oleoyl-FB1), which eluted from the HPLC column after the six O-acyl compounds and in the same sequence as for the O-acyl compounds. The characteristic positive and negative ESI-MS/MS spectra obtained after solid-phase extraction of the culture extract facilitated identification of these N-acyl-FB1 derivatives. The biosynthesis of N-palmitoyl-FB1 by F. verticillioides was verified by spiking the culture extract with synthetic N-palmitoyl-FB1. This is the first report of the separation and mass spectrometric identification of the six O-acyl- and three N-acyl-FB1 derivatives extracted from a F. verticillioides culture. © 2013 Taylor & Francis.
Agency: European Commission | Branch: FP7 | Program: CP-SICA | Phase: KBBE-2007-2-5-05 | Award Amount: 7.37M | Year: 2009
MYCORED aims at developing strategic solutions to reduce contamination by mycotoxins of major concern in economically important food and feed chains. The following toxins and commodities are especially considered in the project: aflatoxins, trichothecenes, zearalenone, fumonisins in wheat/maize food and feed chains; ochratoxin A in the grape-wine and wheat chains; and aflatoxins in the dried fruit chain. Novel methodologies, efficient handling procedures and information, dissemination and educational strategies are considered in a context of multidisciplinary integration of know-how and technology to reduce mycotoxins exposure worldwide. Five work-packages (WPs) will develop novel solution driven strategies to reduce both pre-and post-harvest contamination in feed and food chains. They involve: i) optimization of plant resistance and fungicide use; ii) biocontrol to reduce toxigenic fungi in cropping systems, iii) predictive modelling and optimise logistics; iv) novel post-harvest and storage practices and v) application of new food processing technologies. Two horizontal WPs will develop enabling methodologies for i) advanced diagnostics and quantitative detection of toxigenic fungi and ii) rapid and multi-toxin detection of mycotoxins and relevant biomarkers. The project will significantly build on the outcome of several European projects (through most coordinators/partners of FP5 and FP6) on mycotoxins by supporting, stimulating and facilitating education and cooperation with countries having major mycotoxin concerns related to (international) trade and human health. The direct involvement of ICPC countries (Argentina, Egypt, Russia, South Africa, Turkey) and international organizations (CIMMYT,IITA) together with strong alliances with major research institutions in the USA (3 USDA Centers/5 Universities), Australia, Malaysia will strengthen the project through sharing experiences and resources from several past/ongoing mycotoxin projects in a global context.
Varga J.,Fungal Biodiversity Center |
Varga J.,University of Szeged |
Frisvad J.C.,Technical University of Denmark |
Kocsube S.,University of Szeged |
And 4 more authors.
Studies in Mycology | Year: 2011
Four new species, Aspergillus eucalypticola, A. neoniger, A. fijiensis and A. indologenus are described and illustrated. Aspergillus eucalypticola was isolated from Eucalyptus leaf from Australia, and is related to A. tubingensis and A. costaricaensis, but could clearly be distinguished from them based on either β-tubulin or calmodulin sequence data. Aspergillus eucalypticola produced pyranonigrin A, funalenone, aurasperone B and other naphtho-γ-pyrones. Aspergillus neoniger is also a biseriate species isolated from desert sand in Namibia, and mangrove water in Venezuela, which produces aurasperone B and pyranonigrin A. Aspergillus fijiensis is a uniseriate species related to A. aculeatinus, and was isolated from soil in Fiji, and from Lactuca sativa in Indonesia. This species is able to grow at 37 °C, and produces asperparalines and okaramins. Aspergillus indologenus was isolated from soil, India. This species also belongs to the uniseriate group of black aspergilli, and was found to be related to, but clearly distinguishable from A. uvarum based on β-tubulin, calmodulin and ITS sequence data. Aspergillus indologenus produced the insecticidal compounds okaramins A, B, H, and two types of indol-alkaloids which have not been structure elucidated. Two other species, A. violaceofuscus and A. acidus, are revalidated based on molecular and extrolite data. Aspergillus violaceofuscus was found to be related to A. japonicus, and produced some of the same interesting indol-alkaloids as A. indologenus, and also produced several families of partially characterised extrolites that were also found in A. heteromorphus. Aspergillus acidus (previously known as A. foetidus var. pallidus and A. foetidus var. acidus) is also a valid species, while A. foetidus is a synonym of A. niger based on molecular and physiological data. Two other species described previously, A. coreanus and A. lacticoffeatus, were found to be colour mutants of A. acidus and A. niger, respectively. Methods which could be used to distinguish the two closely related and economically important species A. niger and A. awamori are also detailed. Although these species differ in their occurrence and several physiological means (elastase activities, abilities to utilise 2-deoxy-D-glucose as sole carbon source), our data indicate that only molecular approaches including sequence analysis of calmodulin or β-tubulin genes, AFLP analysis, UP-PCR analysis or mtDNA RFLP analysis can be used reliably to distinguish these sibling species. Aspergillus section Nigri now includes 26 taxa. © 2011 CBS-KNAW Fungal Biodiversity Centre.
Lantos C.,Cereal Research Non profit Ltd. |
Pauk J.,Cereal Research Non profit Ltd.
Russian Journal of Genetics | Year: 2016
The aim of this study was to determine the effect of genotype and induction medium in anther culture of wheat (Triticum aestivum L.). Ten F1 winter wheat genotypes were tested in anther culture (AC) to compare the two most frequently applied induction media (W14mf and P4mf). Androgenesis was induced during the treatment of each tested genotypes and green plants were produced from them using both media. Based on statistical analysis, the genotypes significantly influenced (at the 0.001 probability level) the efficiency of AC (embryo-like structures (ELS), albinos, green plantlets and transplanted plantlets) and the media also had a significant effect on the number of ELS and albino plantlets. Both media can be used for AC in wheat doubled haploid (DH) plant production. The production of ELS and green plantlets was higher in P4mf medium (48.84 ELS/100 anthers, 4.82 green plantlets/100 anthers) than in W14mf medium (28.14 ELS/100 anthers, 4.59 green plantlets/100 anthers). However, the green plant regeneration efficiency of the microspore-derived structures was 16.9% when using W14mf medium, while this value was 9.6% in the case of ELS induced with P4mf medium. The application of W14mf medium thus proved to be time- and labour-saving medium in the large-scale production of DH wheat plants. In our experiments, 267 DH plants were produced for our winter wheat breeding program. The spontaneous rediploidization rate was 32.72%. © 2016, Pleiades Publishing, Inc.
Nagy Z.,University of Szeged |
Nemeth E.,University of Szeged |
Guoth A.,University of Szeged |
Bona L.,Cereal Research Non Profit Company |
And 2 more authors.
Plant Physiology and Biochemistry | Year: 2013
Drought stress has a considerable impact on the ecosystem and agriculture. Continuous water deficit induces early leaf senescence in plants. During this process, chloroplasts are degraded and photosynthesis drastically drops. The objective of this investigation was to look into the regulation of nitrogen and carbon metabolism during water deficit. Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase; EC 18.104.22.168) and the total protein contents inform us of the sink-source relation in plants. Glutamine synthetase (GS, EC 22.214.171.124) isoenzymes are good markers of plastid status (GS2) and the nitrogen metabolism (GS1).Tolerant and sensitive wheat (Triticum aestivum L.) genotypes were tested, which are widely used in agriculture. The amount of protein, Rubisco and GS isoforms in leaves were measured during the grain filling period, as indicative traits that ultimately determine the onset and stage of senescence. The symptoms of senescence first appeared on the oldest and finally on the youngest leaves. Drought stress disrupted the sequentiality of senescence in the sensitive varieties. An untimely senescence appeared in flag leaves, earlier than in the older leaves. Total protein and Rubisco contents decreased and the GS2 isoenzyme declined considerably in the youngest leaves. In the tolerant varieties, however, these physiological parameters did not change under drought, only the sequential senescence of leaf levels accelerated in some cases compared to the control, well-watered plants. Our results revealed that GS is a good indicator of drought stress, which can be applied for the characterization of wheat cultivars in terms of drought stress tolerance. © 2013 Elsevier Masson SAS.
Gasztonyi M.N.,Central Food Research Institute |
Farkas R.T.,Central Food Research Institute |
Berki M.,Central Food Research Institute |
Petroczi I.M.,Cereal Research Non Profit Ltd. |
Daood H.G.,Central Food Research Institute
Journal of Food Composition and Analysis | Year: 2011
This study evaluates the concentration of various forms of ferulic acid in wheat and in wheat varieties grown under comparable organic and conventional conditions over two years. The effect of fungicide application in 2009 was also studied. Soluble conjugated and bound forms of ferulic acid were quantified by HPLC-PAD after extraction, the bound form was present predominantly up to 85-90% of total content. In 2008 the bound form of ferulic acid was measured in the range of 248-550 μg/g, the conjugated form was between 11 and 40 μg/g in all the wheat cultivars as a function of (NPK) treatments. Total ferulic acid content measured in 2009 varied in the range of 275-435; 267-341; 296-378 μg/g, with fungicide and 189-394; 231-366; 182-324 μg/g without fungicide in varieties Békés, Csillag and Petur respectively. In 2008 a significantly higher amount of conjugated ferulic acid was measured in all three investigated cultivars as compared to the content found in 2009 for the same cultivars. As all the samples were treated with fungicide, the main factor was the year (climate conditions). The combination of NPK, fertilizers did not affect significantly the ferulic acid concentration, on the other hand the year (climate conditions) influenced significantly the soluble conjugated ferulic acid content in all fungicide treated varieties. © 2011 Elsevier Inc.
Lehoczki-Krsjak S.,Cereal Research Non Profit Ltd |
Varga M.,Cereal Research Non Profit Ltd |
Szabo-Hever A.,Cereal Research Non Profit Ltd |
Mesterhazy A.,Cereal Research Non Profit Ltd
Pest Management Science | Year: 2013
BACKGROUND: Prothioconazole and tebuconazole are among the most effective fungicides against Fusarium head blight (FHB) of wheat (Triticum aestivum L.). The translocation between the ears and the flag leaves and the kinetics of degradation may influence field efficacy of these active ingredients (AIs). RESULTS: In greenhouse experiments, only traces (<1%) of the total AI content translocated from the flag leaves to the ears, and a maximum of 3.55% from the ears to the flag leaves. From the treated to the non-treated side of the ears, 3.2-15.9% of the AI translocated, depending on cultivar, AI and time. In field experiments, the degradation kinetics in the first 8days after treatment revealed a higher velocity in the flag leaf blades than in the ears, although both were dependent on the type of cultivar. The fungicide treatment resulted in 42.6-100% decreases in FHB traits. CONCLUSIONS: There is no effective translocation of these AIs, only moderate redistribution in the ears, which can be decisive from the aspect of FHB management. The degradation of prothioconazole was faster than that of tebuconazole. Cultivar and environmental effects influenced the degradation kinetics of these AIs, but a high level of protection against FHB was maintained. © 2013 Society of Chemical Industry.
Varga J.,University of Szeged |
Kocsube S.,University of Szeged |
Suri K.,University of Szeged |
Szigeti G.,University of Szeged |
And 4 more authors.
International Journal of Food Microbiology | Year: 2010
Aspergillus niger isolates are able to produce fumonisins in high quantities on agar media with a low water activity. Several agricultural products fit this criterion, including dried vine fruits, dates and figs. Data on the occurrence and role of this species in fumonisin contamination of agricultural products with high sugar content are needed to clarify the importance of A. niger in human health. The mycobiota and fumonisin contamination of various dried vine fruit samples collected from different countries were examined to clarify the role of black Aspergilli in fumonisin contamination of such products. All except two of the examined samples were contaminated with black Aspergilli. Species assignment of the isolates was carried out using sequence analysis of part of the calmodulin gene. The range of fumonisin isomers present in the raisin samples, and produced by A. niger isolates collected from dried vine fruits was also examined using reversed-phase high-performance liquid chromatography/electrospray ionization-ion trap mass spectrometry (RP-HPLC/ESI-ITMS). Among the 30 A. niger/A. awamori isolates identified, 20 were found to be able to produce fumonisins (average contamination: 5.16mg/kg; range: 0.017-19.6mg/kg). The average fumonisin content of the 7 dried vine fruit samples which were found to be contaminated by potential fumonisin producing black Aspergilli was 7.22mg/kg (range: 4.55-35.49mg/kg). The isolates produced several fumonisin isomers also present in the dried vine fruit samples, including fumonisins B1-4, 3-epi-FB3, 3-epi-FB4, iso-FB1, and two iso-FB2,3 forms. Fumonisin B1 was detected for the first time in A. niger cultures. Most of these isomers have previously only been identified in Fusarium species. Our data indicate that A. niger and A. awamori are responsible for fumonisin contamination of dried vine fruits worldwide. The observed levels of contamination are alarming and pose a new threat for food safety. © 2010 Elsevier B.V.
Purnhauser L.,Cereal Research Non Profit Company Ltd |
Bona L.,Cereal Research Non Profit Company Ltd |
Lang L.,Agricultural Research Institute
Euphytica | Year: 2011
The 1BL. 1RS wheat-rye translocation and a wheat-Triticum timopheevii chromosomal introgression carry the Sr31, Lr26, Yr9 and Pm8 genes and the Sr36/Pm6 gene cluster, respectively. The objective of this study was to determine the distribution and impact of these two translocations in 220 wheat varieties registered in Hungary in the last 35 years until 2005. The 1BL. 1RS translocation was introduced into Hungary via wheat cultivars 'Avrora' and 'Kavkaz', which were registered in 1970. New 1BL. 1RS cultivars developed in Hungary first appeared in 1982. After reaching a maximum frequency of 50.0% among cultivars registered in Hungary in 1994, their presence declined steadily to 13.3% by 2005. The Sr36/Pm6 cultivars first appeared in 1980. Their frequency quickly reached 31.8% (1983-1984), but then dropped to between 9.6 and 18.5% (1990-2005). The two main Hungarian breeding programs showed opposing trends in the exploitation of these two translocations. In Martonvásár, 1BL.1RS played a dominant role, being present from 1993 to 1997 in ca. 95% of the released cultivars, while at the same time the use of Sr36/Pm6 was marginal. Conversely, among the Szeged cultivars, Sr36/Pm6 was present at high frequency (44.7% in 2002) with a low share of 1BL.1RS. In artificial field inoculation tests (1985-2003) both of the stem rust resistance genes provided significant resistance in all the years, though Sr36 proved more effective than Sr31. While Pm8 was not effective, except for the last 2 years, Pm6 exhibited significant resistance against powdery mildew in most of the 18 years tested. These data may help breeders to assess the usefulness of wheat-rye 1BL.1RS chromosome translocations and the Sr36/Pm6 resistance gene clusters in their future wheat improvement programs. © 2010 Springer Science+Business Media B.V.
Mesterhazy A.,Cereal Research Non profit Company |
Lemmens M.,University of Natural Resources and Life Sciences, Vienna |
Reid .L.M.,Agriculture and Agri Food Canada
Plant Breeding | Year: 2012
Ear rots caused by different Fusarium spp. are one of the most dangerous food and feed safety challenges in maize production. At present, the majority of the inbreds and hybrids are susceptible. Gibberella and Fusarium ear rots (caused by Fusarium graminearum and Fusarium verticillioides, respectively) are the two main diseases, but more than 10 further Fusarium spp. cause ear rots. Natural infection is initiated by a mixture of the local Fusarium spp., but usually one species predominates. Many maize breeders rely on natural infection to create sufficient levels of disease severity for selection-resistant genotypes; however, there are few locations where the natural infection is sufficiently uniform to make this selection efficient and successful. Thus, an artificial inoculation method normally performed with one fungal species is now used by more breeders. Most published papers on breeding for ear rot resistance are focused on either F. graminearum or F. verticillioides, and reports involving both or more Fusarium spp. are rare. Several reports support the hypothesis that resistance to multiple species especially F. graminearum, F. culmorum and F. verticillioides may be common. Significant differences in genotypic resistance after inoculation exist. Resistance to the two major modes of fungal entry into the ear, via the silk or through kernel wounds, is not correlated in all genotypes. The reason is not clear. When silk channel resistance was assessed, the data from natural and artificial inoculation trials correlated well. Analogous data relating to kernel resistance have not been published. Both native and exotic sources of resistance are important, but surprisingly little information is available. Few papers report on the use of artificial inoculation during inbred development. Most of the publications on inoculation are concerned with testing at later stages when combining ability is tested. Inbreds differ in general and specific combining ability for ear rot resistance. The expression of resistance to disease severity and resistance to toxins is often used as synonyms, but in fact they are not. Higher resistance to visual disease severities mostly results in lower toxin contamination, and the resistance level seems to be the most important factor regulating the toxin content. The mode of inheritance of resistance appears to differ: additive, possibly non-additive effects, digenic (dominant) and polygenic patterns have been identified. Improved phenotyping methods that take into account the influence of stalk rot and the use of several independent isolates are available. The QTLs mostly exhibit small effects and some are validated; however, marker-assisted selection in breeding cannot yet be foreseen. As the severity of natural infections tends to correlate with the artificial inoculation results, the incorporation of artificial inoculation methods in breeding programmes is now the most important task. As genotypic resistance differences between hybrids are high, the registration of hybrids should consider the use of the inoculation tests to choose most resistant hybrids for commercial production. This is the most rapid way to increase feed safety. © 2011 Blackwell Verlag GmbH.