SPRING WHEAT LEAF AND STALK INFECTIONS IN SOIL PROTECTION FARMING IN WEST SIBERIA’S FOREST-STEPPE

Abstract

Spread and damaging action of spring wheat leaf and caulescent infections are examined in grain fallow rotations in West Siberia’s forest-steppe under different weather conditions and levels of minimized tillage. Experimental data were obtained in a stationary field test in the years 1987-2013. The following variants of fall tillage were applied: tillage, deep subsoil tillage with SibIME posts (Siberian Institute of Mechanization and Electrification), minimal flat cutting tillage, zero tillage (no fall tillage). Wheat diseases were studied in three chemicalization backgrounds: control (no chemical means applied), intensive (fertilizers and pesticides applied) and fungicide-free variant in the intensive background. The paper presents multiyear data of research in the dynamics of spring wheat main diseases progress. In the last years, the crop has been recorded to have more frequent epiphytoties of powdery mildew, brown leaf rust and septoriosis. The paper shows the correlation of disease progress index to the degree of vegetation period moisturizing. There is no evidence for the direct influence of soil protective farming reclamation on the progress of aerogenic infections in spring wheat. The increased level of septoriosis spreading under minimized soil tillage is testified to. Fungicides application to control infections in wheat seedlings is estimated in economic terms.