label rates used are indicative only and you should check with your local supplier and chemical label for more accuracy. It may also pay to apply a copper spray following defoliation. With higher than normal disease pressures that have been experienced this last spring/summer, an additional copper spray during dormancy may help fungal and bacterial disease management next season. For copies of any of the fact sheets, please don’t hesitate to contact the office and we can post or email you a copy.
it is unlikely to defoliate naturally and will definitely require a defoliation spray. Unmanaged, this regrowth will become the major inoculum source and infect next season’s growth. It is far more cost effective to apply a defoliation spray of Zinc Sulphate at the end of the season and get 100% control of Rust through complete defoliation rather than rely on the coverage of your airblast sprayer to get adequate control during the following season with pre and/or post infection fungicides. Table 1 indicates the average cost/Ha of fungicides for Rust control compared to Urea and Zinc Sulphate for defoliation. The cost/Ha is based on an average price of the chemical, the actual label rate of application and a water application rate of 2000L/Ha.
still critical to apply a defoliation spray to remove ALL the leaves. Commonly, a 5-7% Urea spray is used for defoliation, but Zinc Sulphate at a rate of approximately 25- 28kg/Ha can also be used. The advantage of using Urea is to aid in “bud building” for next year’s crop. Figure 1 indicates how quickly the population of rust spores can ‘explode’ if left uncontrolled. The message behind this graph is if you don’t maintain adequate control while the rust spore population is low, the numbers can escalate very quickly and management options can be more difficult and less effective, i.e. “The rust didn’t look that bad a few weeks ago, how do I control it now?” Those orchards that became infected with rust early in the season are more likely to have experienced early defoliation, reshooting and even flowering. This new growth is likely to have become infected with rust also; however,
For further information contact: Brett Rosenzweig
Industry Development Officer Almond Board of Australia P 08 8582 2055 or 0429 837 137 E: email@example.com
Please note: The chemical pricing and
Rate (L or Kg/100L)
Qty (L or Kg)/Ha
Fungal protection 750g/kg Mancozeb
Fungal protection 720g/L Chlorothalonil 1
Fungal protection 720g/L Chlorothalonil 2
Fungal protection 250g/L Pyraclostrobin
Table 1: Cost analysis of Rust sprays and defoliation sprays
Figure 2: Incidence of rust in early season versus mid season