Influence of fungicide treatments on disease severity caused by Zymoseptoria tritici, and on grain yield and quality parameters of bread-making wheat under Mediterranean conditions

Abstract

Zymoseptoria tritici is a major fungal pathogen which can cause serious loss in bread-making wheat. In this study, field experiments were conducted over two growing seasons to evaluate the effect of fungicide treatment (1- or 2-sprays of prothioconazole and tebuconazole) on Septoria leaf blotch (SLB) severity, wheat grain yield, hectolitre weight, crude protein and on the SDS (sodium dodecyl sulphate) sedimentation test. The influence of cultivar resistance on fungicide efficacy under Mediterranean conditions was also analysed. The results showed that in years drier than average, fungicide application might not be recommended as SLB severity would be low and the fungicide application itself could reduce grain yield. At high-severity of SLB, one spray of prothioconazole + tebuconazole applied between anthesis and maturation reduced disease severity by more than 50 % and increased grain yield by approximately 20 %. Fungicide treatment did not affect the quality parameters of the grain, measured as crude protein and by the SDS sedimentation test, under these experiment conditions.