|Diseases affecting irrigated and rainfed crops differ due to the temperature and humidity differences obtained during the dry season and the wet hot season. Leaf rust (Puccinia recondita) and stem rust (P. graminis) which are air-borne are the most important diseases in the dry cool season. Powdery mildew (Erysiphe graminis) may develop if irrigation is carried out shortly after planting and/or at short intervals of a week or less. In the wet hot season Helminthosporium sativum causing spot blotch and head blight is the most important disease (Raemaekers 1985). Others are bacterial stripe (Xanthomonus campestris) and head scab (Fusarium spp.). Rusts are rare during this period. Control of these diseases is currently based on varietal resistance. However, there is always a danger of resistance breaking down with the emergence of new strains of the disease.
Smuts (loose and covered) and bunt which are air borne rarely occur in Zambia in both rainfed and irrigated conditions. If seen in a seed crop, they should be reported to the seed inspector immediately and should be removed from the crop. In smuts the ears are replaced by a mass of brown/black spores and the occurrence may result in its failure of neighbouring seed crops which may become infected. Smuts can be controlled by using for example, Vitavax or Baytan seed dressing.
| More Information on Wheat
|Origin And Botany | Varietal Development And Maintenance | Land selection | Land Preparation | Planting | Fertilization | Irrigation | Weed Control | Plant Protection | Field Inspection | Harvesting|