Soil and agronomic factors affecting the inoculum potential of Polymyxa betae Keskin in Belgium
1991
Goffart, J.P. (Centre de Recherches Agronomiques de l'Etat, Gembloux (Belgium). Station de Phytotechnie) | Maraite, H.
A survey of 52 fields located in the various sugar beet-growing areas in Belgium was done in 1987 to detect eventual relations between the inoculum potential of Polymyxa betae (vector of Beet necrotic Yellow Virus causing rhizomania disease) and either soil or agronomic factors. The inoculum potentials were ranging from 0.01 to 13.6 Infective Units (IU) per gram of soil. They appeared to depend significantly on soil pH and Ca or Mg soil contents. Low potentials (0.98 IU/g) were related to pH H20 et KCl7.0 and Ca and Mg contents respectively 245 and 10 mg/100 g of soil. On the other hand, high potential were detected to be related to pH7.7 and Ca and Mg contents respectively 365 and 20 mg/100 g of soil. Agronomic factors such as calcareous or organic amendments, wich induce variations of pH and Ca content in the soil, were also related to differences in the inoculum potentials. The rational use of lime and others factors determining the pH and Ca content of soil are discussed. Their interest in an integrated control policy intended to reduce the expression of P. betae in the field and to avoid a development of rhizomania in Belgium, up to now restricted to Belgian Polders, is also presented.
显示更多 [+] 显示较少 [-]