Minutes of the 5 th NORBARAG meeting fungicide subgroup January 30 th 2013, 09.00 17.00 Tallin, Estonia 1. Welcome and introduction Gunilla Berg (GB) wished everybody welcome, and appreciated that around 30 people were attending the subgroup meeting. The group had representatives from Denmark, Estonia, Finland, Latvia, Lithuania Norway and Sweden. Bayer, DuPont, Syngenta, BASF, Makhteshim and Agrolab were represented in the meeting. 2. Acceptance of agenda The agenda of the meeting was accepted. Election of a new chairman was added to the agenda. 3. Reports Minutes of the 4 th NORBARAG fungicide subgroup meeting in Sweden 2011 was presented and approved. Short reports from the 6 th EPPO meeting resistance meeting http://www.eppo.int/meetings/2012_meetings/resistance.htm General recommendations from 2011 12 will be updated to cover 2013 and uploaded. Lists of known resistant pathogens in the Norbarag region containing cases from the cereal and potatoes area will be updated and is included in the General recommendations. The list will aim at covering all countries in the region in order to provide a better overview. The list should only include known and confirmed cases of resistance. The present table could create the basis for the database. We will keep the simple table updated until further progress in an electronic version has been made. 4. Diseases in potatoes Collaboration on monitoring Several companies (Syngenta and Mabeno) presented data on fungicide resistance collected in 2012 in the area of cereals and potatoes. Presentations are uploaded on the home page. The weather 2012 was favorable for late blight (Phytophthora infestans). Mabeno presented data from a late blight survey 2012 and all samples showed full sensitivity to dimethomorph. Syngenta showed also data from late blight testing in 2012 and no resistance to mandipropamid (Revus) has been detected. Isolates with resistance to metalaxyl have previously been found in Denmark, Sweden, Norway and Finland and in 2012 resistance were found at one site in Denmark by Syngenta. The finding fits with the locality of genotype Blue13 in the surveys carried out by Flakkebjerg (the genotype Blue 13 or 13_A2 has ben tested resistant to metalaxyl in other countries, e.g. UK). This genotype surveys showed that Blue13 was detected in 12 % of the isolates in 2011 and increased to 25 % in 2012. Generally, the level of resistance is known to be reduced by the start of the next season, but with potential risk of metalaxyl resistance in certain areas seem to have
increased. In Norway investigations from Bioforsk showed metalaxyl resistance at two of 10 locations and also one isolate was resistant to propamocarb. Results from resistance testing on early blight (Alternaria solani) to stobilurins carried out by SLU, Uppsala was presented and no F129L mutation was found, but some samples had a very strange sequence in cytochrome b. The testing of A. alternata is not finalised yet but some isolates with G143a mutation may be found in Sweden. The role of A. alternata in the disease complex is unclear and needs to be clarified. Bent Nielsen and Eva Edin will coordinate sampling and testing for late blight and early blight for 2013. 5. Fungicide sensitivity status of cereal pathogens Andreas Mehl, Bayer gave a good overview over FRAC activities and presented data. The presentation will be uploaded on the home page. 6. Collaboration on monitoring in cereal diseases Several companies (BASF, Bayer, Syngenta, Mabeno and Du Pont) presented data on fungicide resistance collected in 2012 in the area of cereals. Presentations are uploaded on the home page. The following specific discussions took place based on the collected samples in 2012 (Table 1): Diseases in Norbarag region 2012 It was a wet season with high disease pressure in Finland Estonia, Latvia, Lithuania and middle parts of Sweden which gave severe attacks of Septoria, DTR, Stagnospora but also brown rust and mildew. Netblotch was frequent in spring barley. Lots of Fusarium head blight was found includingd both Michrodochium and Fusarium spp. In southern Sweden and Denmark the weather was more dry and disease pressure were generally lower. Even so significant attacks of Septoria, netblotch, Ramularia and brown rust in barley were seen. Yellow rust was a severe problem in Sweden in susceptible cultivars. Generally the disease control levels in major field crops have been satisfactory. Septoria tritici and sensitivity to DMI Results from sensitivity tests were presented by both BASF, Bayer, Syngenta and Mabeno. Data was shown from 2011 and 2012. In the data from the companies there was a tendency to a minor shifting taking place from 2009 to 2012. The data from Flakkebjerg showed a more pronounced shift for prothioconazole in Sweden for 2010, 2011 and 2012. Many isolates have high EC50 values, but field performance is ok or not to bad. In Denmark the shift was minor in 2010, but more pronounced in 2011 and 2012. For epoxiconazole the sensitivity seems to be more stable. Bayer, BASF, Syngenta are all looking at the CYP51 mutations and altogether 10 Norbarag trials have been carried out in Denmark, Sweden and Lithuania 2011 2012 in order to investigate the impact on R types by different treatments to control Septoria. The results are shown in the presentation from Lise uploaded on this webpage. The monitoring for this disease will continue in 2013 and could possibly be extended to include also Finland and the Baltic countries. In 2013, the leaves should again be collected at
GS 75. 20 leaves per field will be collected and sent to Flakkebjerg. The 20 leaves should preferably be placed on a piece of paper so that it is easy to see the symptoms. The leaf samples should be air dryed for 1 2 days before posted. The samples will be split and Denmark will make EC50 values of some of the samples, and Bayer, BASF and Syngenta has promised to help with characterization for the CYP 51 mutations on specific isolates again in 2013. Stagonospora nodorum sensitivity to QoIs Resistance has previously been seen in samples from Sweden, tested by Eva Edin, SLU. Data from 5 field trials in 2010 in Norway indicated that the strobilurins neither gave effective control of S. nodorum/s. tritici nor good yield responses in comparison with other products. Samples from the whole region were collected 2011 and tested by Andrea Ficke, Bioforsk, Norway. Resistance was shown in several samples throughout the region. The results are shown in the presentation from Andrea and is uploaded on the webpage. Reference isolates need to be included in the screening. Microdochium nivale/majus sensitivity to QoIs France and the UK have previously found widespread occurrences of resistance. Previously monitoring (BASF, Bayer, Du Pont) has shown high levels of QoI resistance for both M. nivale and M. majus in several of the countries in Norbarag in the region. E.g. resistance in Denmark was found to be 76 %. Flakkebjerg has been testing grain samples (from 2003 2007) from both wheat and barley. Already in 2003 the first signs of resistance could be detected in wheat samples and in the 2007 the resistance was major. Major resistance was also found in the barley samples from 2007. This indicates that head blight or seed borne M. nivale cannot be expected to be controlled by strobilurins any longer. Drechslera tritici repentis (Tan spot or DTR ) sensitivity to QoIs The mutations G143A has been found in samples collected from Denmark, Sweden, Latvia and Lithuania. In some samples minor proportions of F129L and G137R has also been seen. In 2011 and 2012 low level of G143A was found in Finland and in 2012 high level of G143A was also found in Norway. The level is quite similar in the countries. Despite quite high levels of particularly G143A, it has still been seen from trials that strobilurins can add to an increase in the efficacy with respect to control of DTR. The group felt that there was no need to continue the monitoring in 2013 as the level has not changed a lot during the year in which the monitoring was carried out. Drechslera tritici repentis (Tan spot or DTR ) sensitivity to DMI A large variation in EC50 values for tan spot isolates has been measured when screened for sensitivity to prothioconazole, propiconazole and epoxiconazole. Clear signs of crossresistance between DMIs were measured, but no sign of mutations in the CYP51 gene was found when analyzed. This specific investigation was part of a post doc project carried out by Karin Thygesen at AU in 2011. Sequencing of parts of some of the isolates did not verified any clear signs of changes, which can be related to the use of triazoles. In 2012 trials triazoles are still found only to provide moderate levels of tan spot control. High input is needed if disease pressure is high. Ramularia collo cygni sensitivity to QoIs
Very high levels of QoI resistance have previously been found on Danish samples from both 2008 and 2009. Samples from 2010 collected in Sweden have also shown high levels of QoI resistance. In Danish and Swedish field trials the performances have been very low using strobilurins. Ramularia was frequent in 2012. Drechslera teres (Net blotch) sensitivity to QoIs Since 2008 Danish samples showed presence of F129L mutations and positive samples were also found from Sweden. The level of resistance in Denmark 2008 2011 has stayed around 50 60 %, but decreased to around 25 % in 2012. The level in Sweden for 2008 2010 was around 20 %. In 2011 2012 the level decreased to around 5 8 %. Samples from Latvia have also shown low levels. Data from 2010 2012 showed no presence of F129L in Balticum, Norway or Finland. Occurrences of F129L in the field populations in a trial from Flakkebjerg in 2010 and 2011 showed that F129L can lead to low control by Amistar. The efficacy of Comet and Aproach (Acanto) were not similarly influenced by the occurrence of F129L. Monitoring data from trials at Flakkebjerg in 2009 2011 gave a clear indication that following the use of strobilurins the field populations of F129L increased, regardless of whether or not the strobes were used alone or in mixtures (see presentation from Denmark). There was a wish to continue the monitoring on Drechslera teres in 2013 as the picture is still quite variable in the NORBARAG region. Drechslera teres (Net blotch) DMI sensitivity Data from 2008 showed a major variation in EC50 values for triazoles with propiconazole as the product giving the highest EC50 values. Imazalil gave the lowest level of EC50 values when Danish and Swedish isolates were screened. Field performances from imazalil have previously been variable and it has been discussed, if this relate to resistance. The field performance from imazalil in 2010 in Sweden had been acceptable and no data from 2011 or 2012 has been collected. There is still a lack of old reference isolates of net blotch, as the present references are originating from post propiconazole time. MTT, Finland presented efficacy data from field trials carried out during 1998 2012. Many trials have been carried out with propiconazole (Tilt) and the data showed a clear decrease in control during the years, indicating that ther has been a change in sensitivity. Rhynchosporium secalis sensitivity to QoIs Monitoríng data was presented by Du Pont and in 2011 isolates from Denmark, Finland, Norway, Sweden and Latvia were tested and In 2012 isolates from Denmark, Finland and Sweden were tested. No resistance where found in either 2011 or 2012. One isolate with G143A mutation was found in France in 2008, but since then no shifting has taken place anywhere in Europe. The sensitivity to DMI s and SDHI s has been checked and no signs of shifting have been found. Wheat mildew sensitivity to metrafenone and proquinazid Resistance to metrafenone in the wheat mildew population has been found in several countries since 2009. BASF provided data from 2012 which indicate that the level of moderate resistance isolates has slightly increased but the proportion of major resistance was stable compared to 2010. In 2012 around 1 % of the population was found with major resistance factor and 26 % (16 % in 2011) with moderate resistance factor. In Denmark were
2012 found 8 % medium resistant isolates and 3 % of major resistance. In Sweden 1 of 20 samples was moderate resistant. The situation will be followed also in 2013. It was recommended to include mildew samples from the Baltic region and Finland in 2013. The samples can be forwarded to EPILOGIC. BASF will continue sampling by car (EPILOGIC) from a tour across Denmark and Sweden. Du Pont presented data from Sweden with mildew testing and no resistance was found in 2011 or 2012 to proquinazid (Talius ). Data collected in Germany by EPILOGIC has showed some changes in the sensitivity to Talius. Eyespot in wheat No activity in 2012. SDHI sensitivity to Septoria, Netblotch BASF, Bayer and Syngenta, showed data from sensitivity testing to SDHI products. Extensive monitoring programmes have been carrried out since 2003. Until 2011 all isolates have been sensitive. In 2012 one single isolate of Septoria tritici from a trial site in N France was outside the baseline. Also in 2012 the sensitivity of 2 isolates of net blotch from N Germany were outside the baseline. Rf values was still low and good field performance had still been obtained. It is important to collect baseline data now before the use of new SDHI fungicides will expand. It has been seen that pathogens quite easily can develop resistance to SDHI fungicides, as e.g. seen for Botrytis in strawberries. An updated list of samples proposed for 2013 see Table 2 Ramularia in sugar beet Sensitivity of Ramularia beticola to both propiconazole, epoxiconazole, pyraclostrobin and difenoconazole were tested on isolates from 2011 and 2012. Opera (epoxiconazole + pyraclostrobin) is widely used for control of Ramularia in the field. All isolates showed similar sensitivity although propiconazole gave significantly higher EC50 values. AU will try to continue screening isolates of R. beticola in order to get a broader picture of the sensitivity. Mildew in sugar beet strobilurin resistance Mildew from 10 locations in Denmark and Sweden were tested in 2011 and 2012 in a collaboration between Aarhus University, NBR and BASF. No sign of resistance was seen. The field performance from pyraclostrobin, which is used as a solo product in Sweden has still provided full control. 7. Next meeting Next meeting will be in Riga, Latvia in the first week of February (week 6) 2014. New chairman is Bent J. Nielsen, Aarhus University, Flakkebjerg, Denmark..
Table 1: Samples collected in 2012 Table 2: Samples proposed collected in 2013