Wheat stripe rust control using fungicides in New Zealand

Abstract

A field trial in 2005 used eight fungicide treatments and two wheat cultivars Karamu and Kohika differing in susceptibility to wheat stripe rust Fungicides were applied at different growth stages of the crop and different levels of stripe rust Disease severity assessments percent leaf area infected for individual plants and leaves were made at regular intervals and area under the disease progress curve (AU DPC) was calculated Mean AU DPC was lowest in the Full Protectant and Late window treatments for all leaves on both cultivars and greatest in the Nil plots for both cultivars Mean AU DPC generally increased with leaf age for Kohika so that flag (F) leaves had the lowest and F3 the greatest mean AU DPC The same trend occurred on Karamu leaves but was not statistically significant Two welltimed fungicide applications achieved as good control of stripe rust in both Karamu and Kohika as the full fungicide treatment