The status of wheat diseases and disease research in warmer areas.
The results of a questionnaire sent to wheat researchers in the warmer areas of the developing world are presented with additional material obtained from a literature review. Data on disease importance are presented by temp. zones. Bipolaris sorokiniana [Cochliobolus sativus] was confirmed as the most economically important foliar pathogen in all zones. Puccinia recondita and Fusarium scab (caused primarily by F. graminearum [Gibberella zeae]) were important in all zones while Drechslera tritici-repentis occurred mainly in the coolest zone of the warmer areas. In the 2 hottest zones, Sclerotium [Corticium] rolfsii and Fusarium spp. were the most damaging soilborne diseases and in the coolest area, Fusarium spp. and Gaeumannomyces graminis dominated. Results of chemical control trials indicated that the above diseases caused significant actual and potential losses in these areas. An overview of new results on key diseases (C. sativus, P. recondita, D. tritici-repentis and soilborne disease complex) in the warmer areas is also presented, along with recommendations for future research.