
AN independent group of plant scientists appointed to help tackle Yellow Canopy Syndrome (YCS) in sugarcane crops has endorsed research directions into the condition.
The scientific reference panel is part of the Solving Yellow Canopy Syndrome research project, funded by the Sugar Research Development Corporation, the Department of Agriculture, Fisheries and Forestry Queensland and BSES Limited.
The panel includes Professor John Lovett from Plant Biosecurity Cooperative Research Centre (PBCRC), Dr Andre Drenth from University of Queensland, and Dr Geoff Inman-Bamber from Crop Science Consulting.
The panel recently travelled to the Burdekin and Herbert cane-growing regions to assess first-hand YCS in the field.
They also met with the Sugar Research Australia (SRA) project team and industry representatives.
From their first inspections the panel confirmed the view of SRA staff – that the condition is complex and is not yet fully understood.
The panel reviewed all aspects of the project and endorsed the general directions being taken.
They will soon recommend on any adjustments to the project.
During the inspections the SRA team and the panel found that:
- Symptoms of YCS were observed in both plant and ratoon crops.
- Symptoms were seen in advanced and younger crops.
- Varieties may differ in susceptibility to YCS but the symptoms were seen in varieties old and new, and in ‘noble’ cane.
- Affected crops were observed on heavy and light soil types.
- Symptoms may appear in one row but not in neighbouring rows. Monitoring is needed to determine whether the condition spreads over time.
- Root systems may show an absence of vigorous, white roots.
- Leaf blades, typically, develop ‘burning’ along one side – probably the side which unrolls first as the leaf develops.
- Leaves and other parts of the plant may show red and purple colouration.
- Similar symptoms were observed in several other grass species.
Progress has been made in ruling out some possible causes and setting up new trials to learn more, with two new trials are now underway.
Trial one will look at planting material and the impact of stress.
Based at the Burdekin facility, this recently planted trial seeks to understand how water stress and Imidacloprid treatments impact on clean and affected cane.
Trial two looks at Imidacloprid with field trials established in the Herbert cane-growing region – in collaboration with HCPSL – to investigate the effects of Imidacloprid on YCS expression and severity.
A trial was set up – under optimal conditions – to see if YCS could be transmitted via planting material.
After 10 weeks YCS symptoms weren’t showing in young cane, even when the plant source was severely affected.
Germination was impaired, however, with reductions of up to 20 per cent when severely YCS-affected plant source was used.
A water stress treatment has now been introduced to the trial.
After a few weeks of this treatment some typical stress-related yellowing has been seen – but nothing resembling YCS symptoms. The trial is ongoing to see how the cane progresses under these conditions.
Sites have been identified and established which will be used to monitor and track the development of YCS in two successive crops.
Soil sampling has started and data is being collected to assist with mapping and cataloguing site history and inputs.
Assessment is being undertaken to discover the industry impacts of YCS on this year’s yield and sugar. This data is being collected and YCS-affected blocks are being monitored through to the mill.
An information sheet which can help growers identify YCS and compare it against other conditions has now been published which aims to educate those in the industry industry on what to look for to ensure that YCS is identified accurately and can then be monitored.