Efficacy of fungicide treatments on the winter wheat senescence, grain yield, protein concentration and yield

Field experiments were conducted over 3 years to assess the effects of fungicides (F) containing strobilurins and triazoles on grain protein concentration, grain and protein yield of the winter wheat cv. 'Zentos'. The efficacy of F use on the parameters tested depended on the weather conditions of the harvest year and on the F applied. F use prolonged retention of green canopy of wheat plants in 2003-2004. Chlorophyll concentrations in flag leaves at the end of plant vegetation, i.e. in the fifth week after F treatment, were higher in the plots treated with strobilurins compared with those treated with triazole propiconazole and untreated plots. F application significantly increased grain yield in all F-treated plots in 2003 and 2004, and in most plots in 2002. F use only insignificantly affected protein concentration in grain, which amounted to 12.6-14.8% DM in the plots treated with strobilurins, 13.0-14.6% DM - with triazoles and 12.8-14.5% DM in untreated plots. Protein yield was higher for the strobilurin-treated plots (with a small exception) than for those treated with propiconazole.