Now is the time for pro-active wheat disease prevention
The Threat
Winter brought mild and wet conditions with it and, as a consequence, NZ growers up and down the country are now facing an escalating threat from diseases prevalent in wheat crops. In 2017/18, Bayer Disease watch saw significant yield reductions occurring due to disease attacks by speckled leaf blotch, stripe rust and leaf rust. With a very real potential for decimated profits, there are some key factors to take into consideration before applying your fungicide programme.
The Timing
One thing cannot be mistaken; for effective disease control, timing is critical. To ensure effective disease control for your crops and attain the optimum yield, it is vital that a 25-28 day spray interval is maintained from the first application date of your fungicide programme.
During last season’s research, Bayer conclusively found that effective wheat disease control resulted in substantially increased profits (see chart below). Tested in individual trials, each disease was controlled using a DMI fungicide at GS32, followed by an application of Aviator® Xpro at both GS39 and GS65. The profit was calculated using a wheat price of $400/t and average on-farm fungicide prices.
Where speckled leaf blotch was controlled, growers enjoyed a profit of $615/ha. For leaf rust control, a profit of $1,315/ha was achieved whilst $1,390 profit was seen for stripe rust control.
These findings prove the importance of a robust fungicide programme alongside careful timing. With flag leaf emergence occurring at GS39, this is a critical stage for healthy crop development. At this point, the top two leaves of a wheat crop have emerged and these deliver approximately 70% of the crop’s yield.
GS39 isn’t far away. Ensure you apply Aviator® Xpro 1.0L/ha 25-28 days after your GS31/32 fungicide. To conclude this programme, Prosaro should be applied in conjunction with a strobilurin fungicide at GS65.
Wheat Spray Programme