Foliar fungicide now important tool for Blackleg control
Foliar fungicide application is now seen as an additional control strategy especially in medium to high rainfall areas according to Australian canola industry leader, Trent Potter.
Blackleg is a major issue in canola production in Australia and the severity of blackleg has risen in recent years due to an increased area and intensity of production. Although not common, yield losses of 50 per cent and greater have been recorded.
Trent, who has been involved with the canola industry since 1976 in agronomy, breeding, pathology and industry representative roles, said the combination of farming systems, rotations and the ability of blackleg to overcome varietal resistance means that growers have to maintain a wide range of management measures to at least “keep up” with blackleg.
“Fungicide application is now seen as an additional control strategy especially in medium to high rainfall areas where canola crops are grown in close proximity to each other and previous canola stubble,” Trent said.
“Foliar fungicides are now a useful additional control measure especially when they follow a fungicide applied at sowing as either a seed dressing of a fertiliser amendment.”
Trent said varietal selection used to be the key management strategy for blackleg, but as growers reduced the number of years between canola crops and increased the area grown to canola, the amount of canola stubble increased and so too the inoculum levels.
Trent has recently been involved with trial work including MIRAVIS®, Syngenta’s new foliar fungicide for the control of blackleg and white leaf spot (pending APVMA approval), including trials he conducted in 2013-15 and 2017.
He said MIRAVIS has shown consistent control of blackleg in all trials conducted under heavy blackleg pressure.
“MIRAVIS has performed consistently and when blackleg pressure is high, MIRAVIS plots have shown very good crop vigour. In 2014, Jockey followed by MIRAVIS was the highest yielding treatment.
“In 2015 and 2017, which was a low disease pressure site, MIRAVIS has performed as well as other control measures.
“In 2013, the blackleg pressure at the site was low but MIRAVIS gave very good control of white leaf spot.”
MIRAVIS has a SDHI Mode of Action - ADEPIDYN™ - which is the first SDHI belonging to a new chemical group within FRAC group 7 fungicides.
Syngenta Product Lead, Angus Rutherford said the new fungicide is expected to significantly benefit Australian canola growers.
“MIRAVIS offers a step change in control versus current industry standards for blackleg,” Angus said.
“Trial results indicate a strong return on investment for growers in commercial crops.”
For more information on compatibility, formulation, application and trial results, click here.