Psa protection through pollination
As in previous years, the effects of Psa infection appears to have arrived around Labour weekend for many orchards across the regions.
Leaf-spotting is more predominant in Hayward blocks, but Psa effects have also been reported for Gold3 on Bounty and on less sheltered Red9 blocks. These symptoms are resultant of infections occurring in previous weeks and are a prompt for a continued Psa control programme up to and through the flowering period.
Presence of inoculum in the canopy increases the risk of fruit drop so growers should be applying summer rate copper or Aureo Gold to manage infection risk and maximise flower potential. Actigard applied one week before flowering is also recommended through this important period.
A reminder for growers that Psa affected flowers should not be collected for milling, so monitoring of blocks historically providing flowers is a good idea to help forecast flower availability for pollen mills.