A critical assessment of three previously published indirect methods based on acidic hydrolysis using superacids for the determination of “free” and “total” deoxynivalenol (DON) was carried out. The ...modified mycotoxins DON-3-glucoside (D3G), 3-acetyl-DON (3ADON), and 15-acetyl-DON (15ADON) were chosen as model analytes. The initial experiments focused on the stability/degradation of DON under hydrolytic conditions and the ability to release DON from the modified forms. Acidic conditions that were capable of cleaving D3G, 3ADON, and 15ADON to DON were not found, raising doubts over the efficacy of previously published indirect methods for total DON determination. Validation of these indirect methods for wheat, maize, and barley using UHPLC-MS/MS was performed in order to test the accuracy of the generated results. Validation data for DON, D3G, 3ADON, and 15ADON in nonhydrolyzed and hydrolyzed matrices were obtained. Under the tested conditions, DON was not released from D3G, 3ADON, or 15ADON after hydrolysis and thus none of the published methods were able to cleave the modified forms of DON. In addition to acids, alkaline hydrolysis with KOH for an extended time and at elevated temperatures was also tested. 3ADON and 15ADON were cleaved under the alkaline pH caused by the addition of KOH or aqueous K
2
CO
3
to “neutralize” the acidic sample extracts in the published studies. The published additional DON increase after hydrolysis may have been caused by huge differences in matrix effects and the recovery of DON in nonhydrolyzed and hydrolyzed matrices as well as by the alkaline cleavage of 3ADON or 15ADON after the neutralization of hydrolyzed extracts.
Response of 35 spring wheat varieties and lines (of four Triticum species) to spray inoculation with Fusarium culmorum was evaluated in field experiments over three years (2010–2012). Data on ...mycotoxin deoxynivalenol (DON) content were complemented by symptom scores and determination of the percentage of Fusarium damaged kernels and percent reduction of thousand grain weight and of grain weight per spike due to infection. Resistance to Fusarium head blight (FHB) determined on the basis of the five mentioned traits was variable in all the examined genotype groups and very high only in the non-adapted check variety Sumai 3. The common wheat landrace Červená perla, four T. dicoccum genotypes (May Emmer, Weisser Sommer, Tábor, and Rudico), T. spelta (Ruzyně), and the commercially grown bread wheat variety Vánek can be considered as moderately resistant to FHB. DON accumulation was significantly higher in the modern common wheat varieties than in the other Triticum species and common wheat landraces. The latter nonetheless showed similar average reductions in grain weight per spike due to infection as did current spring wheat varieties. It is particularly important that DON content was found to be low and least variable not only in Sumai 3 but also in some T. dicoccum (Rudico and Tábor) and T. spelta (Ruzyně) genotypes. It was documented that FHB-resistant emmer and spelt wheat materials have some outstanding grain-quality parameters (e.g. very high protein content) and can be progressively utilized particularly in breeding wheat for alternative use and growing in organic farming systems. It is important to make substantial progress towards developing resistance in common spring wheat, because most current varieties other than Vánek and Trappe were found to be moderately susceptible or susceptible to FHB.
Evaluation of resistance to Fusarium head blight in wheat using different sources of inoculum Sip, V., Vyzkumny Ustav Rostlinne Vyroby, Prague (Czech Republic); Chrpova, J., Vyzkumny Ustav Rostlinne Vyroby, Prague (Czech Republic); Stockova, L., Vyzkumny Ustav Rostlinne Vyroby, Prague (Czech Republic)
Czech Journal of Genetics and Plant Breeding,
01/2011, Letnik:
47, Številka:
4
Journal Article
Recenzirano
Odprti dostop
The response of four winter wheat cultivars, differing in resistance to Fusarium head blight (FHB), to spray inoculation with four selected Fusarium graminearum isolates, mixture of these isolates ...and frequently used F. culmorum isolate B was studied in five field and glasshouse experiments during 2008-2010. Analyses of variance showed highly significant main and interaction effects of cultivar, inoculum source and environment (year-trial) on all five examined traits indicative of disease severity, yield loss and accumulation of mycotoxins. The relations between traits were not evidently influenced by the isolate. Resistance of host genotypes and environmental conditions accounted for a greater proportion of the total variation (8-36%) than the inoculation source (isolate) that substantially influenced the accumulation of the mycotoxin deoxynivalenol (12%), but expressed relatively low effects on symptom scores, percentage of damaged kernels and reductions of yield components (2-4%). Two-way and three-way interactions accounted for 25-40% of variation in the examined traits, which indicates great importance of multi-environment tests, using different Fusarium isolates for inoculation. Separate inoculation with F. graminearum isolates, differing in aggressiveness, did not appear to be more advantageous than their use in mixture that showed medium or below-average aggressiveness in all traits. The application of an isolate mixture could be recommended as a less costly alternative to inoculation with single isolates in trials repeated in different years and/or locations. It was indicated by these experiments that especially the detection of resistance/moderate resistance to FHB could be facilitated by the use of a carefully selected mixture of isolates. However, the application of aggressive isolates (isolate B of F. culmorum in these experiments) appeared to be beneficial to eliminate FHB susceptible materials in the breeding process.
Resistance of 31 winter wheat varieties (bred in 6 European countries) to Fusarium head blight (FHB) was evaluated in field trials lasting for three years (2007, 2008, 2009) after artificial ...inoculation with Fusarium culmorum. Deoxynivalenol (DON) concentrations, symptom scores, the percentage of damaged grains and the reduction in thousand grain weight and grain weight per spike were determined. The 31 varieties and also 120 advanced breeding lines were examined for the presence of gibberellic acid (GA) insensitive semi-dwarfing genes to evaluate their effect on FHB. The conditions of experimental years highly influenced the performance of all characters. The highest production of DON occurred in 2008 as both air temperature and relative humidity were high. In all years, a moderate resistance to accumulate DON (at the level of Swiss variety Arina) was detected in the Czech varieties Bakfis, Federer, Baletka, Samanta and Sakura. Among these varieties, Federer showed a low accumulation of DON at a relatively higher symptom expression and greater reduction of grain weight per spike, but the other four varieties and the reference variety Arina expressed resistance in all the examined traits. The varieties Pitbull, Cubus, Kodex and Bagou were found to be highly susceptible to FHB. The presence of the dwarfing allele Rht-D1b resulted in a significantly higher mean symptom score and also in a higher affection of the other traits. Nonetheless, the analysis of frequency distributions in symptom scores showed the presence of resistant lines also among the GA insensitive lines, but with a lower frequency than in the group of GA sensitive genotypes. Plant height had a relatively great effect on the manifestation of the disease. It is therefore suggested that the adverse impact of Rht-D1b on FHB resistance could be to a high degree excluded by opting for taller Rht-D1b genotypes.
DON CONTENT IN CZECH CEREALS ŠTOČKOVÁ, Lenka; SÝKOROVÁ, Světlana; CHRPOVÁ, Jana
Cereal research communications,
01/2008, Letnik:
36
Journal Article
Recenzirano
A survey ofFusariummycotoxin deoxynivalenol (DON) in cereals intended for human consumption was carried out in Czech Republic for eight-year period (2000 – 2007). Wheat and barley samples were ...collected directly from farmers so as to represent most of regions in Czech Republic. Immunochemical method (ELISA) was used for analyses. 82% of 444 wheat samples and 70% of 481 barley samples were positive for DON content and maximum levels for DON according to Commission Regulation (EC) 1881/2006 were exceeded in 3,6% out of wheat samples and 1,7% out of barley samples. Further the influence of region, variety, average year temperature and sum of precipitation on levels of DON was observed and evaluated.
A lateral-flow technique using colloidal gold-labelled monoclonal antibodies (ROSA ® DON Quantitative Test) for the rapid detection of deoxynivalenol (DON) content was compared with two commonly ...exploited analytical methods ELISA and HPLC-UV. The grain samples of 10 winter wheat varieties, showing varying level of resistance to accumulation of DON, spray inoculated withFusarium graminearumunder field conditions were the subject of this study. The values of DON content obtained with the use of three different methods showed high conformity. ROSA ® DON Quantitative Test could be considered as a reliable, rapid and cost-effective on-site screening technique for determination of DON in grain samples.
Microgreens from common and tartary buckwheat genotypes were evaluated for total flavonoid content (rutin, quercetine and kaempferol separately), bound phenolic acids content, carotenoids and ...α-tocopherol content and antioxidant activity. The results have shown that in common and tartary buckwheat microgreens antioxidant activity was found. High level of flavonoids, carotenoids, and α-tocopherol was detected as well. Higher amount of flavonoids was found out in tartary buckwheat microgreens. No significant differences were detected between common and tartary buckwheat microgreens in content of phenolic acids. Microgreens of both common and tartary buckwheat represent potential nutritional sources for alternative vegetable in the Czech Republic.
Vsebnost celokupnih flavonoidov (posebej rutina, kvercetina in kempferola), vezanih fenolnih kislin, karotenoidov, α-tokoferola in antioksidantna aktivnost so bili raziskani pri mladih rastlinah navadne in tatarske ajde. Ugotovljena je antioksidativna aktivnost izvlečkov mladih rastlin navadne in tatarske ajde ter visoka vsebnost flavonoidov, karotenoidov in α-tokoferola. Posebej visoka vsebnost flavonoidov je bila ugotovljena pri tatarski ajdi, medtem ko glede na vsebnost fenolnih snovi ni bilo razlike med mladimi rastlinami navadne in tatarske ajde. Mlade rastline tako navadne kot tatarske ajde so možen alternativni vir zelenjave v Češki republiki