Abstract
In 2010–2019 altogether 2824 Botrytis isolates from 203 Northern German strawberry fields were examined for resistance to the currently registered fungicides fenhexamid, trifloxystrobin, boscalid, fluopyram, fludioxonil and cyprodinil as well as two compounds phased out in 2009 and approx. 1975, viz. iprodione and thiophanate-methyl (respectively). In each year of the survey the levels of resistance were very high (>65%) to trifloxystrobin, high (>30%) to iprodione, fenhexamid, fludioxonil and cyprodinil, and moderate (10–35%) to thiophanate-methyl. Rising shares of resistance from 20% to >50% and from nearly zero to 10% were recorded for boscalid and fluopyram, respectively. The share of isolates with resistance to five or all six of the registered fungicides rose from 2% in 2010 to 20% in 2013, remaining at this elevated level thereafter. These multi-resistant B. cinerea isolates frequently or almost always possessed resistance also to thiophanate-methyl or iprodione (respectively), whereas isolates with no resistance to the current fungicides were also sensitive to both non-registered compounds. Some of these sensitive isolates belonged to B. pseudocinerea which occurred at variable shares of 3–16% of the total population.
| Translated title of the contribution | Ten Years of Botrytis Fungicide Resistance Monitoring in Northern German Strawberry Production |
|---|---|
| Original language | German |
| Journal | Erwerbs-Obstbau |
| Volume | 62 |
| Issue | 2 |
| Pages (from-to) | 155-161 |
| Number of pages | 7 |
| ISSN | 0014-0309 |
| DOIs | |
| Publication status | Published - Jun 2020 |