Comparison of Disease Occurrence and Green Leaf Area (GLA) of Winter Wheat Depending on the Forecrop and Differentiated Fungicidal Protection Used

Abstract

Comparison of Disease Occurrence and Green Leaf Area (GLA) of Winter Wheat Depending on the Forecrop and Differentiated Fungicidal Protection UsedThe effect of the forecrop and differentiated chemical plant protection on the intensity of fungal leaf diseases of winter wheat were studied from 1999-2008. Five (I-V) separate experiments were conducted in Mazury (Szestno I,), Żuławy Wiślane (Lisewo II), and Powiśle (Wielgłowy III, IV and Radostowo V). The intensity of diseases varied. Powdery mildew (Blumeria graminis) was noted in relatively low or trace intensity. On the other hand, there was a large amount of necrotic leaf spot complexes caused byMycosphaerella graminicola, Stagonospora nodorum, Pyrenophora tritici-repentisandFusariumspp. In 2000, 2001 and 2003 brown rust (Puccinia recondita) was noted in high intensity. The applied treatments were very effective in reducing fungal disease on leaves. The surface of the upper leaves (Green leaf area - GLA) with no symptoms of infection and fungicide use were significantly higher than in the control. It was also found that the GLA of crops grown after oilseed rape was higher than the GLA of crops grown after wheat.