Abstract
Rhizoctonia root rot of wheat and barley caused by Rhizoctonia solani AG-8 continues to cause significant yield losses, especially in no-till cropping systems in low to medium rainfall regions across southern Australia. This study was conducted to determine if liquid banding of the fungicides Uniform® and EverGol® Prime could significantly reduce yield losses attributed to Rhizoctonia. From 2011-2013, 28 trials were conducted at 14 sites across SA and WA; Uniform® was evaluated in 10 barley and 11 wheat trials, and EverGol® Prime in 6 barley trials sown using a knife point furrow opener. Sites had significant levels of Rhizoctonia prior to seeding and treatments included banding fungicide 3-4 cm below the seed, on the soil surface behind the press wheel and a combination of both. Seed treatments plus/minus banding fungicide below the seed were also evaluated. Vibrance™ and EverGol® Prime seed treatments produced significant yield responses in 4/21 and 2/6 trials, respectively. Uniform® banded below the seed at different rates produced significant yield responses in 21/33 trials and EverGol® Prime in 2/8 trials. The split Uniform® treatment applied to the surface and below the seed produced the greatest proportion of significant yield responses, 14/19 trials, with net yield increases of up to 0.87 and 0.53 t/ha in barley and wheat, respectively. For EverGol® Prime this split treatment resulted in 2/5 trials showing significant responses with the largest net gain being 0.44 t/ha in barley. The APVMA is currently reviewing submissions to have Uniform® registered for banding on the surface and below the seed, and EverGol® Prime below the seed only .