Effect of application rate on the sensitivity of Erysiphe graminis f.sp. tritici to fenpropimorph

✍ Scribed by Burnett, Fiona J.; Zziwa, Miriam C. N.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 194 KB
• Volume: 51
• Category: Article
• ISSN: 1526-498X
• DOI: 10.1002/(sici)1096-9063(199711)51:3<335::aid-ps645>3.0.co;2-y

✦ Synopsis

Two sprays of fenpropimorph per season were applied to a winter wheat Ðeld trial, at a range of rates, which included the full commercial rate, in order to test the e †ect of fenpropimorph sprays on the sensitivity of Erysiphe graminis f.sp. tritici. While a reduction in the sensitivity of the mildew isolates was detected after fungicide application, this was not dependent on the rate of fungicide applied. Reduced rates were not found to induce a larger shift towards insensitivity than the full commercial rate. Powdery mildew isolates were collected from 1993 to 1996 and their sensitivity to fenpropimorph determined in order to monitor sensitivity changes in the population. While a decline in sensitivity was noted from season to season, there was no correlation between a lower sensitivity and the rate of fenpropimorph previously used. Isolates collected in Scotland were found to be signiÐcantly less sensitive than those sampled in the south of England.