RUST OF WHEAT

Overview: Stripe rust, leaf rust and stem rust are three important foliar diseases of wheat in southern Australia, (Figure 2.2). Where favourable conditions occur and susceptible varieties are grown, significant yield losses may be incurred and even total crop loss. These three diseases have similar lifecycles.

The three rusts of wheat in Australia can only survive on living plant material, with the dominant host being wheat and to a much lesser extent other cereals and grasses. This is why wheat rusts are of greater concern following wet summers when there has been opportunity for volunteer wheat to grow freely and carry over rust from the end of one season to the start of the next. Following dry summers rust is generally of less concern.

All three rusts are wind dispersed and can be spread large distances (>1,000 km) by wind. This dispersal makes rust diseases common across a district. Therefore, inadequate rust control on one farm can have implications for rust development on neighbouring farms.

Even though these rusts are extremely damaging they can be effectively controlled through managing inoculum carry over during the summer/autumn, the cultivation of resistant varieties and/or the use of fungicides. Avoiding growing susceptible and very susceptible cultivars is the primary method of controlling rust. There is also a range of seed, fertiliser and foliar fungicides that contribute to effective rust control. Where an integrated management approach is utilised the effects of rust will be minimised.

                   STRIPE RUST                           LEAF RUST                           STEM RUST

 

Figure 2.2 Distinguishing characteristic of stripe, leaf and stem rust of wheat

STRIPE RUST OF WHEAT