There are a range of foliar diseases that need to be considered when growing wheat. The diseases currently of concern (in no order) in Victoria are the rusts (stripe rust, leaf rust and stem rust), yellow leaf spot, septoria tritici blotch and powdery mildew. The relative importance of each of these diseases is dependent on the degree of resistance in a crop, the amount of inoculum present in a paddock or district, and the local seasonal conditions. Fortunately, growers have access to a range of strategies to minimise losses (both in grain yield and grain quality) associated with these diseases and the best control of foliar diseases is achieved when a combination of approaches are used.

Generally, long term control of the important foliar diseases of wheat can be achieved when the growing of cultivars that are highly susceptible (i.e. those rated as Susceptible and Very Susceptible) to regional important diseases is avoided (see Resistance Ratings). Fortunately, for all important foliar diseases of wheat there are varieties with resistance available. However, very few varieties have resistance to all foliar diseases. Therefore, growers need to be aware of the priority diseases for their region and where adequate resistance is not available implement additional control strategies.

Strategies that minimise inoculum levels can help reduce the impact of foliar diseases during a season. For the rusts, which can only survive from one season to the next on living plants (particularly wheat) controlling volunteers growing over summer and autumn can decrease inoculum carry over. For stubble borne diseases (e.g. yellow leaf spot), avoiding planting into infected wheat stubble can contribute to reducing the impact of these diseases.

For all foliar diseases of wheat there are fungicide control options available. However, it is important not to rely on fungicides as the only control option and be aware of strategies that minimise the likelihood of resistance to fungicides developing (see Fungicides). In general fungicides provide the best control outcome when applied early in a disease epidemic and used as part of an integrated disease management strategy.

Following the identification and control of each of the important foliar diseases of wheat in Victoria is discussed.

 

Please note: This book is also available on AppleBooks