Diagnosing crop diseases and effective treatment
Farmers who attended BCG’s fungicide diagnostic schools and technical workshops said they now feel more confident about implementing disease management strategies on their farms.
The event, which was staged at Quambatook, Horsham and Westmere, focused on crop disease diagnosis and treatment, spraying efficiency and efficacy and pulse and oilseed phenology and physiology.
Foundation for Arable Research (FAR) director Nick Poole opened the diagnostic school with a tour of the fungicide diagnostic trial.
Mr Poole encouraged attendees to get down into the wheat, barley and pulse crops to see if they could find any evidence of disease.
Interesting and robust discussions ensued about disease control according to weather conditions, cultural practice and likely season returns.
Mr Poole explained that the systemic nature of common fungicides used to treat disease means that once they infiltrate the leaf they can only move outwards to the tip.
“This means that the part of the leaf that was not exposed at spraying might still be infected and subsequent spraying may be required,” he said.
“For Mallee growers the decision can be based on how likely it is that disease-conducive weather conditions will prevail, as well as the disease resistance ratings of their varieties, expected season outcomes and farming practices.”
But for growers in wetter regions such as the Wimmera, Mr Poole said a second fungicide spray was usually recommended.
With the understanding of how fungicides work, the importance of good crop coverage and canopy penetration was discussed.
“Obviously, the deeper the penetration, the better protection for the crop,” Mr Poole said.
Taking up this point, spraying consultant Craig Day from Spray Safe & Save said careful planning and an understanding of the application process was needed to maximise fungicide performance.
“We, as an industry, need to learn to manage to spray with coarser spray droplets,” he said.
“In order to achieve this, I believe we need to share the responsibility with the person applying the fungicides and take an active interest in the application process, not just the process of selecting a product.
“This includes researchers, advisors, machinery agents, chemical corporations and applicators.”
Mr Day discussed the effect of tractor speed and nozzle selection on fungicide performance.
Using his purpose built demonstration sprayer he showed growers the differences between a range of spray nozzles.
Clearly, some nozzles are more capable of deeper canopy penetration that others.
To combat disease, pests and weeds in pulse crops, Pulse Australia industry development manager Trevor Bray said it was important that growers were able to recognise crop growth stages so they could respond to any threat appropriately.
“Fungicide needs and timing vary according to the crop type and variety resistance,” he said.
“Canopy closure also needs to be considered for fungicide application and this is influenced by crop management (sowing date, variety, row spacing and location).
To bring growers up to speed on pulse growth stages Mr Bray used potted examples to demonstrate what lentil, vetch, chickpea and pea plants should look like at various stages of growth.
When applying fungicides he reminded growers to be aware of weather conditions, with fungicides best applied to pulses ahead of rain.
Canola growth stages and disease management was also covered by BCG research scientist Simon Craig at Quambatook and International Plant Nutrition Institute (IPNI) regional director Dr Rob Norton at Horsham.
With harvest on the horizon farmers were interested in learning how to recognise when canola is ready to be windrowed or desiccated ahead of harvest.
This interactive session saw farmers share their experiences, highlighting the pros and cons of direct heading over windrowing canola crops.
Growers deemed this event well worth their time with the majority claiming that as a result they would implement changes on their farms.
