Management of rhizoctonia bare patch in the South Australian mallee using a modified direct drilling system, deep-banded urea, and sowing time in relation to the break in the season

Abstract

Tillage experiments in the South Australian mallee, over 8 years (1990–97), have demonstrated that cultivation directly below the seed at sowing controls rhizoctonia bare patch as effectively as 1 or 2 cultivations prior to sowing. When combined with a short chemical fallow and the use of press-wheels, this modified direct drilling technique can yield as well as, or better than, conventional farming systems.

The combination of modified direct drilling and deep-banded urea increases the control of the disease in the first 2 weeks after the break in the season. In the first 2 weeks after the break, deep banding urea at sowing is more likely to increase yield, than modified direct drilling with urea broadcast at tillering, when both treatments are compared with standard direct drilling. In a reduced tillage system, a cultivation 6–11 days after the break in the season may be more effective in reducing bare patch than a cultivation at other times after the break.