Influence of maize straw amendment on soil-borne diseases of winter wheat

Abstract

A field experiment was conducted during the 2006–2007 wheat growing season at Baoding, Hebei Province, China, aiming at exploring the influence of different amendment rates of maize straw on winter wheat soil-borne diseases induced by Rhizoctonia cereali, Gaeumannomyces graminis and Bipolaris sorokiniana in field conditions. Wheat root vitality, ion infiltration, SOD activity, MDA content and microbial population of the tillage layer were measured. The results showed that the occurrence of three soil-borne diseases tested was significantly different under different amendment rates. During the greening stage and jointing stage, the disease indexes of three soil-borne diseases were reduced significantly by treatments at the maize straw amendment rates of 7500 kg · hm−2 and 3750 kg · hm−2. However, disease indexes of wheat common rot and sharp eyespot increased dramatically when the amendment rate increased to 15000 kg · hm−2. At the amendment rate of 15000 kg · hm−2, wheat root vigor and SOD activity decreased, and ion infiltration and cell membrane-lipid peroxidation level increased, respectively. In the meantime, higher amounts of bacteria and actinomycetes were recorded in the 7500 kg · hm−2 amendment rate treatment, while a higher amount of fungi was recorded in the 15000 kg · hm−2 amendment rate treatment.