Evaluation of diflubenzuron for porina control in South Otago

Previous work assessing the suitability of using diflubenzuron for porina control in New Zealand has shown it to be effective in most areas of New Zealand, but results from the southern South Island have been inconsistent.Trials were conducted in South Otago in 1994, comparing two rates of diflubenzuron, and 1995, comparing diflubenzuron with chlorpyrifos.Diflubenzuron, applied at the manufacturers recommended rate, gave 78% and 80% control of porina in 1994 and 73% control in 1995.This compares with an average of 95% control achieved using chlorpyrifos in 1995.The results show that diflubenzuron can give significant levels of control of porina in South Otago and is a viable option for farmers.