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.
DTA curves were run for the ethylenebisdithiocarbamate fungicides maneb, mancozeb and zineb in a nitrogen atmosphere. Zineb
produces a curve quite different from the others, with weak endothermic peaks at 166°C, 252°C and 293°C. Maneb and mancozeb
have a relatively strong endothermic peak at 185–190°C corresponding to carbon disulphide evolution and a weaker endothemic
peak at 290°C corresponding to hydrogen sulphide evolution.
Maneb samples and some mancozeb samples also had a minor endothermic peak at 235°C, but this peak was lost after solvent extraction,
which proved that it was due to an impurity or impurities. Elemental sulphur was found in the extract and on mixing sulphur
with mancozeb, the peak at 235°C made its appearance.
There is no distinguishing feature between the DTA curves for maneb and mancozeb. The shapes of the curves are, within experimental
limits, indistinguishable, which means that the temperatures and energies of decomposition are the same.
The chemist is left with the question whether differences in structure between maneb and mancozeb should lead to different
Authors:M. Carmona, D. Barreto, R. Moschini, and E. Reis
Veterinary and Agricultural University Yearbook, 1974, Copenhagen, pp. 108–117.
Sutton, J.C., Steele, P. 1983. Effects of seed and foliar fungicides on progress of net blotch and yield in barley. Canadian Journal of
Authors:L. Tanács, E. Gregová, K. Bodnár, F. Lantos, and T. Monostori
Ruske, R.E., Gooding, M.J., Dobraszczyk, B.J. 2004. Effects of triazole and strobilurin fungicide programmes, with and without late-season nitrogen fertiliser, on the baking quality of Malacca winter wheat. J. Cereal Sci. 40 :1