Background/context:

Fiji leaf gall caused by the Fiji disease virus (FDV) has threatened the viability of the sugar industry in the past in NSW, Bundaberg and Mackay. The virus is transmitted by planthoppers of the species Perkinsiella. Fiji leaf gall can cause total crop loss in susceptible varieties, and epidemics in Australia and Fiji have threatened the viability of the sugar industries in these countries.

 Aim:

With a view to minimising the risk of further losses to the sugarcane industry the aims of this project were: 1) to understand the interactions between FDV, the planthopper vector and sugarcane varieties and 2) to develop a robust method for rating sugarcane varieties for resistance to Fiji leaf gall.

Major Outcomes:

A glasshouse cultivar screening technique was developed that is highly correlated with field reaction. This technique has been adopted by the BSES Limited breeding program and will allow earlier and more efficient screening of cultivars for susceptibility. This will ensure that cultivars developed for market have high resistance to Fiji leaf gall. Support for control of the disease through strict quarantine measures was provided by our findings that planthoppers from northern Queensland that have had no previous exposure to FDV are more efficient at acquiring and transmitting FDV suggesting that if FDV spread to northern Queensland that the endemic planthoppers would spread the disease efficiently. Planting of resistant cultivars combined with the strict quarantine on the movement of sugarcane between regions remain the best approach for preventing future epidemics of Fiji leaf gall disease. The knowledge produced by this research project is providing new insights into plant-virus-vector interactions and is being used to develop a new screening method that may be useful to breeders. The net benefits of the outcomes from this research have been calculated at around $1 million over a 10-year period – a 2-fold return on the Centre’s investment in this project.

For more information contact:

Dr Barry Croft
Bureau of Sugar Experiment Stations
Phone: +61 (0)7 5496 3357
Email: BCroft@bses.org.au