Septoria tritici blotch in wheat

This publication is currently being reviewed. An updated version will be made available shortly.

Septoria tritici blotch (STB) is the most significant stubble-borne foliar disease of wheat in high-rainfall zones (HRZ). It is caused by the fungal pathogen Zymoseptoria tritici. In these zones when continual wet conditions occur, it can cause losses of up to 60 per cent in susceptible varieties. It requires regular and ongoing management in the HRZ and, in some seasons, in medium-rainfall zones (MRZ).

Key points

• Septoria tritici blotch (STB) is a damaging stubble-borne foliar disease found in high and, sometimes, medium-rainfall zones. It can cause yield losses of up to 60 per cent
• Damage is caused to the leaves, grain size and quality, and yield n An integrated management approach is required, incorporating variety selection, timely fungicide application, paddock selection, management of host environments such as stubbles and avoiding early sowing of highly susceptible varieties
• Consult a current cereal disease guide for the latest STB ratings of wheat varieties
• Further reduced sensitivity of STB to fungicides can be delayed with appropriate strategies
• Modern farming systems, particularly stubble retention and using limited resistant varieties, support STB survival
• The risk of disease outbreak is maximised by susceptible wheat-onwheat rotations. These should be avoided.