The effect of fungicides on the content of photosynthetic pigments in spring wheat plants

Abstract

   Relevance. The number of scientific papers dealing with the indirect effect of the use of fungicides during the growing season on wheat yield through their effect on physiological processes and pigment composition in plants of this crop is not numerous. There are only a few domestic and foreign works on this issue. The need to conduct research on the effect of treatments with fungicidal preparations on the pigment composition in plants is dictated by the fact that modern chemical plant protection products, being physiologically active substances, can have a certain effect on plants by inhibiting or enhancing their physiological and biochemical processes.   Methods. The material for laboratory and field studies were five fungicides («Amistar Trio, CE» (125 g/l propiconazole + 100 g/l azoxystrobin + 30 g/l ciproconazole); «Triada, СSC» (140 g/l propiconazole + 140 g/l tebuconazole + 72 g/l epoxiconazole); «Folicur, CE» (250 g/l tebuconazole); «Evito T, CE» (250 g/ l tebuconazole + 180 g/ l fluoxastrobine); «Soligor, CE» (224 g/l spiroxamine + 148 g/l tebuconazole + 53 g/l protioconazole)), that are used to protect spring wheat from diseases during the growing season. To study their effect on the content of pigments in the leaf apparatus, we carried out treatments with these preparations of spring wheat varieties Daria and Leningradskaya 6 in the maximum application rate. The amount of pigments in the experimental and control variants was determined by the spectrophotometric method followed by statistical processing of the data obtained using a computer program for dispersion analysis “Diana 1”.   Results. The preparation “Triada, СSC” on the 4th day after single application on spring wheat plants of the Daria variety led to a significant decrease in the content of chlorophylls and the total amount of pigments in the leaf apparatus. Significant changes in the direction of increasing the content of photosynthetic pigments were detected on the 8th day after the 2nd treatment with “Soligor, CE” used in field experiments on the Daria variety.