Recent changes to maximum residue limits (MRLs) for iprodione have affected the pre-harvest interval (PHI) guidance provided in printed wallcharts. The most current PHI information is available on the portal and should be used as the primary reference.
Initial advice from MPI was that Codex and those countries using Codex had changed iprodione’s MRL to 0.3 mg/kg of fruit, where previously this was 10 mg/kg. The resulting PHI was then set at ‘insufficient data’, meaning that iprodione should not be applied for fruit destined to those markets, or for the all markets category. These countries include Cambodia, Kuwait, Malaysia, Myanmar, Philippines, Singapore, Thailand and UAE.
This restriction would have impacted on disease control for the early season, and on resistance management across a number of other fungicides.
The change from insufficient data to set a PHI, to that of shuck fall, has come about from a combination of reviewing the available research, as well as using the results from the residue tests in our Residue Management Scheme in combination with the export spray diaries. This information was enough for MPI to review and reset the PHI. We do not have sufficient confidence to support applications after shuck fall or pre-harvest for those countries listed above.
The following countries retain a PHI of 1 day and include Australia, China, Hong Kong, Indonesia, Japan, Korea, New Caledonia, New Zealand, Taiwan, USA and Vietnam.
There has also been changes to the printed export PHI chart for iprodione in apricots so the updated portal version should be used.
As always please talk with your spray rep and exporter to confirm that applications of agrichemicals are suitable.
This is a good result for the industry as we work towards new chemistry for brown rot and botrytis control.