FHB of wheat is a serious regional problem in Punjab. An outstanding bread wheat line RP-1/10 and three durum lines viz; WH 896, HD 4715 and MPO 1192-resistant to FHB have been identified. Aphids are important insect-pests in wheat and the FHB severity can be significantly reduced by more than 30%, by controlling these aphids by the application of Monocrotophos (insecticide) at boot + heading or at heading alone. A single application of Monocrotophos @ 0.1% followed 72h later by Tilt@0.1% at heading significantly improved FHB control and grain yield. The strobilurin fungicide-Amistar@ 0.1%, applied as a single spray at heading, was the best treatment in reducing FHB severity and improving grain yield. The efficacy of the fungicide was much higher in bread wheat compared to durum wheat. The results suggest that wheat aphids are important in FHB development and their management through insecticide in combination with fungicide can reduce FHB and improve grain yield.
Authors:S. Pirgozliev, R. Ray, S. Edwards, M. Hare, and P. Jenkinson
Saprophytic microflora and non-toxin producing Microdochium spp. capable of causing Fusarium head blight (FHB) have been suggested to affect the development of FHB caused by Fusarium spp., the occurrence of mycotoxins and the efficacy of fungicides for the control of the disease. The effects of metconazole and azoxystrobin on the interactions between Fusarium culmorum and Microdochium spp., Alternaria tenuissima or Cladosporium herbarum on FHB symptom development, Tri5 DNA concentration and deoxynivalenol (DON) production were studied under glasshouse conditions. Results indicated that the sequence of infection of wheat heads and the relative timing of fungicide application can significantly affect FHB severity and the resulting mycotoxin contamination of harvested grain. Introduction of A. tenuissima, C. herbarum or Microdochium spp. to wheat heads at GS 57 before inoculation with F. culmorum at GS 65 generally resulted in increased FHB severity, Tri5 DNA and DON concentration in harvested grain. The greatest increases of FHB severity (266%), Tri5 DNA (79%) and DON (152%) were observed when Microdochium spp. were introduced first at GS 57 and F. culmorum inoculation followed at GS 65. Metconazole generally reduced FHB severity, Tri5 DNA and DON concentration in grain but azoxystrobin was most efficient at reducing DNA of Microdochium spp. in grain.
Fusarium fungi . Eur. J. Plant Pathol. 109 , 577 – 587 .
Dahl , B. and Wilson , W. W. ( 2018 ): Risk premiums due to FusariumHeadBlight (FHB) in wheat and barley . Agric. Syst. 162 , 145 – 153 .
De Oliveira , E. A. D. ( 2014 ): The
Authors:Etienne Duveiller, Monica Mezzalama, J. Murakami, J. Lewis, and T. Ban
Resistance to FusariumHeadBlight (FHB). In: Ban et al. (eds), The Global Fusarium Initiative for International Collaboration. Proc. of a Strategic Planning Workshop, CIMMYT, Mexico, March 14–17, 4–7.
Fusarium Head Blight (FHB) is one the most important diseases in small grain cereals and often is caused by a complex of
species. Some of these species are able to produce one or several mycotoxins. The spatial distribution of the disease and associated mycotoxins was examined in this study. Results were mapped and analysed with a geographic information system (GIS). Correlations between the incidence of the deoxynivalenol (DON) producing
species and DON contamination of kernels were rather weak. The level of DON contamination seemed to be less influenced by the frequency of DON producing
species than by other factors.
Authors:K. Gromadzka, L. Lenc, C. Sadowski, A. Baturo-Ciesniewska, J. Chełkowski, P. Goliński, and J. Bocianowski
Fusarium head blight (FHB) of cereals is one of the most important pre-harvest diseases worldwide. One possible method to reduce the intensity of FHB and mycotoxin levels is to apply fungicides to wheat at the flowering stage. This paper reports the efficacy of fungicides to control FHB and reduce the associated mycotoxin biosynthesis. In a two-year experiment eight combinations of fungicides were tested. Ear inoculation with a suspension of conidia of Fusarium culmorum representing the DON chemotype, confirmed by PCR assay, was conducted during anthesis. All fungicides significantly reduced FHB severity. The best control and the highest wheat yield were obtained after the application of spiroxamine + prothioconazole at GS 29-32, combined with prothioconazole + fluoxastrobin at GS 49-55 (yield 166.5% of the control) or tebuconazole and prothioconazole (165.8%). All the other protection programs resulted in higher yields (117.1–138.5% of the control). A clear relation was observed between the disease intensity and mycotoxin concentrations.
Authors:A. Tekauz, J. Mitchell Fetch, B. Rossnagel, and M. Savard
Fusarium head blight (FHB) of oat in western Canada was determined to be caused by a complex of Fusarium species, the composition and proportions of which varied considerably among years, and between Manitoba and Saskatchewan, the two main oat production regions (provinces) in western Canada. The levels of deoxynivalenol (DON), associated with Fusarium graminearum infection, were considerably higher in oat than in wheat and especially in barley, when levels of DON were compared to those of F. graminearum on seed, suggesting that oat may stimulate production of the mycotoxin by this causal species during the infection process, compared to that in other cereals. Testing of oat cultivars and lines for reaction to FHB indicated that while differences existed, these were relatively small. ‘Naked’ oats, in general, were more resistant. Several of the exotic oat accessions tested appeared to have superior levels of resistance and these are being used as parents in crosses to improve resistance in adapted, high quality oats.
Pathogenic variation was studied in 16 fungal isolates of four Fusarium head blight (FHB) species on two modern Syrian bread and durum wheat cultivars using an in vitro Petri-dish test. Three aggressiveness criteria: germination rate reduction, standardized area under disease progress curve (AUDPCstandard), and coleoptile length reduction were evaluated. Regarding AUDPCstandard, intra- and inter-species variability in aggressiveness was detected. The other two aggressiveness criteria did not distinguish fungal isolates within and among species. It seems that AUDPCstandard may be used to measure aggressiveness of FHB on wheat at early stages. The three aggressiveness parameters were not significantly correlated. Cultivar-specific aggressiveness has not been detected. It was not possible to cluster the isolates based on their species origins because of similarity in pathogenic level among the 16 fungal isolates. Bread wheat was more resistant to FHB infection than durum wheat in vitro. The two tested modern cultivars were shown to exhibit moderate to high FHB resistance levels.