Fungicide Resistance Action Committee
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In case you are interested in background information for QoI fungicides, please follow this link: Information on QoI fungicides


FRAC Recommendations for QoI fungicides

(Reviewed January 2024; Includes FRAC Code Group 11A)

 
General Use Recommendations (all Crops)

(Reviewed January 2024; No changes)

Strategies for the management of QoI fungicide resistance, in all crops, are based on the statements listed below. These statements serve as a fundamental guide for the development of local resistance management programs.

Resistance management strategies have been further enhanced in order to be proactive and to prevent the occurrence of resistance to QoI fungicides developing in other areas and pathogens. Specific guidelines by crop follow the general guidelines given here.

A fundamental principle that must be adhered to when applying resistance management strategies for QoI fungicides is that:

  • The QoI fungicides (azoxystrobin, coumoxystrobin, dimoxystrobin, enoxastrobin, famoxadone, fenamidone, fenaminostrobin, fluoxastrobin, flufenoxystrobin, kresoxim-methyl, mandestrobin, metominostrobin, orysastrobin, pyraoxystrobin picoxystrobin, pyraclostrobin, pyrametastrobin, pyribencarb, triclopyricarb trifloxystrobin) are in the same cross-resistance group; FRAC Code 11. 
  • The QoI fungicide in subgroup A (metyltetraprole), Code 11A fungicide, is not cross resistant with Code 11 fungicides in pathogens with G143A mutation. 
  • Fungicide programmes must deliver effective disease management. Apply QoI fungicide based products at effective rates and intervals according to manufacturers’ recommendations. Effective disease management is a critical component to delay the build-up of resistant pathogen populations. 
  • The number of applications of QoI fungicide based products within a total disease management program must be limited whether applied solo or in mixtures with other fungicides. This limitation is inclusive to all QoI fungicides. Limitation of QoI fungicides within a spray programme provides time and space when the pathogen population is not influenced by QoI fungicide selection pressure. 
  • Limitation of the total number of QoI applications is detailed in the specific crop recommendations. In consideration of the cross-resistance profile of subgroups 11 and 11A, the maximum allowed number of QoI-containing sprays is increased by one, where both QoI fungicides (code 11) and QoI fungicides in subgroup A (code 11A) are included in a spray program in a given cropping season. All crop-specific recommendations will be regularly reviewed based on sensitivity monitoring. 
  • A consequence of limitation of QoI fungicide based products is the need to use it in a spray program with effective fungicides from different cross-resistance groups (refer to the specific crop recommendations). 
  • QoI products, containing only the solo QoI fungicide, should be used in single or block applications in alternation with fungicides from a different cross-resistance group. Specific recommendation on the number of consecutive treatments (size of blocks) is given for specific crops. 
  • Mixture partners for QoI fungicides should be chosen carefully to contribute to effective control of the targeted pathogen(s). The mixture partner must have a different mode of action, and in addition it may increase spectrum of activity or provide needed curative activity. Use of mixtures containing only QoI fungicides (including two-way mixtures of code 11 fungicide and code 11A fungicide) must not be considered as an anti-resistance measure. 
  • An effective partner for a QoI fungicide is one that provides satisfactory disease control when used alone on the target disease. 
  • QoI fungicides are very effective at preventing spore germination and should therefore be used at the early stages of disease development (preventive treatment).
     

For a printer friendly version of the General Use Recommendations see section 2.2.1 of the latest "Minutes of the QoI Working Group Meeting" below.


Specific Recommendations by Crops

Specific crop recommendations for FRAC code group 11 A will be prepared in the FRAC QoI Working Group before the product is available for use.

QoI Guidelines: Cereals

(Reviewed January 2024; No changes)

Where the guidelines were followed, field performance of QoI containing spray programmes was good. It continues to be essential to use non-cross resistant mixture partners (e.g. SBIs, multi-sites) to ensure robust disease management. This will also help to delay the evolution of resistance, especially in regions with no resistance or where resistance is at low levels.

Therefore, the recommendations remain unchanged.

Guidelines for using QoI fungicides on cereal crops.

  1. Apply QoI fungicides always in mixtures with non-cross resistant fungicides to control cereal pathogens. At the rate chosen the respective partner(s) on its/ their own has/ have to provide effective disease control. Refer to manufacturers' recommendations f or rates. 
  2. The maximum number of QoI-containing sprays is 3, but only when QoI fungicides belonging to both QoI Groups (code 11 and 11A) are included in a spray program. QoI fungicides belonging to the individual Codes (11 or 11A) should not be applied more than 2 times either individually or when mixed together. 
  3. Apply QoI fungicides according to manufacturer’s recommendations for the target disease (or complex) at the specific crop growth stage indicated. 
  4. Apply the QoI fungicide preventively or as early as possible in the disease cycle. Do not rely only on the curative potential of QoI fungicides. 
  5. Split / reduced rate programmes, using repeated applications, which provide continuous selection pressure, accelerate the development of resistant populations and therefore must not be used.

For a printer friendly version of these use recommendations see section 2.2.1 of  the latest "Minutes of the QoI Working Group Meeting" below.

QoI Guidelines: Vines

(Reviewed January 2024; No changes)

Apply a maximum of 4 QoI fungicide containing sprays against any disease per vine crop, and a maximum of 33% of the total number of applications.

Powdery mildew (Uncinula necator / Erysiphe necator)

  1. Apply QoI fungicides according to manufacturer's recommendations for the target disease at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. Apply a maximum of 2 QoI fungicide-containing sprays targeted against powdery mildew per vine crop, preferably in mixture (co-formulations or tank mixes) with effective mixture partners from different cross-resistance groups. 
  3. Apply QoI fungicides preventively. 
  4. QoI fungicides used solo should be used in strict alternation with fungicides from a different cross-resistance group. 
  5. Apply QoI fungicides used in mixture in a maximum of two consecutive applications in alternation with fungicides from a different cross-resistance group. In areas where resistance has been confirmed, apply QoI fungicides in strict alternation.

Downy mildew (Plasmopara viticola)

  1. Apply QoI fungicides according to manufacturer's recommendations for the target disease at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. Apply QoI fungicides preventively. 
  3. Apply a maximum of 3 QoI fungicide containing sprays targeted against downy mildew per vine crop, only in mixture with effective partners from different cross-resistance groups. 
  4. Apply QoI fungicides in single or block application in alternation with fungicides from a
    different cross-resistance group.

For a printer friendly version of these use recommendations see section 2.2.2.2 of the latest "Minutes of the QoI Working Group Meeting" below.

QoI Guidelines: Pome fruit

(Reviewed January 2024; No changes)

Scab (Venturia inaequalis, Venturia pirina)

  1. Apply Apply QoI fungicides according to manufacturers' recommendations for the target disease (or complex) at the specific crop growth stage indicated and adapted to size of trees. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. QoI fungicides must be applied only in mixture with partners contributing to the effective control of the target pathogens. 
  3. Apply QoI fungicides preventatively. Under high disease pressure the spray interval should not exceed 7-10 days. 
  4. Apply a maximum of 3 QoI containing sprays per crop. A maximum of 4 QoI fungicide applications may be used where 12 or more applications are made per crop. 
  5. A maximum of 2 consecutive QoI fungicide sprays is preferred. Where field performance was adversely affected apply QoI containing fungicides in mixtures in strict alternation with fungicides from a different cross-resistant group.

For a printer friendly version of these use recommendations see section 2.2.2.3 of the latest "Minutes of the QoI Working Group Meeting" below.

QoI Guidelines: Potato and Tomato

(Reviewed January 2024; No changes)

Late blight (Phytophthora infestans)
  1. Apply QoI fungicides according to manufacturer's recommendations for the target disease (or complex) at the specific crop growth stage indicated. Effective disease control management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. Where QoI fungicide products are applied alone, do not exceed 1 spray out of 3 with a maximum of 3 sprays per crop. Do not use more than 2 consecutive applications. 
  3. Where QoI fungicide products are applied in mixtures (co-formulations or tank mixes) do not exceed 50% of the total number of sprays or a maximum of 6 QoI fungicide applications whichever is the lower. Do not use more than 3 consecutive QoI fungicide containing sprays.

Early blight (Alternaria solani, Alternaria alternata)
  1. Where QoI fungicide products are applied solo do not exceed 33% of the total number of sprays or a maximum of 4.
  2. Where mixtures (co-formulations or tank mixes) are used, do not exceed 50% of the total number of sprays or a maximum of 6 QoI fungicide applications, whichever is the lower.
  3. Where resistance has been confirmed, QoI fungicides must be applied only in mixture with partners contributing to the effective control of the target pathogens.

QoI Guidelines: Soybeans

(Reviewed January 2024; No changes)

QoI fungicides control soybean diseases including rust, which is a major disease in Latin America and has been detected recently in the USA. 

In order to ensure sustainable use of QoIs the Working Group recommends:

  1. Apply QoI fungicides according to manufacturer's recommendations for the target disease (or complex) at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. Use QoIs preventatively or as early as possible in the disease cycle. 
  3. Use QoIs preferably in mixtures (co-formulations or, where permitted, tank mixes) with fungicides from a different cross-resistance group. At the rate chosen, each partner on its own has to provide effective disease control. Refer to manufacturers’ recommendations for rates. In regions where target site mutations in key target soybean pathogens are present mixtures are mandatory. 
  4. Limiting the number of sprays containing QoI fungicides is an important factor in delaying the build-up of resistant pathogen populations.
Good agricultural practices must be considered to reduce source of inoculum, disease pressure and resistance risk, e.g. no multiple cropping, implement and respect soybean-free periods, consider varietal tolerance, reduce the planting window, give preference to early-cycle varieties or endorse the destruction of volunteers.

QoI Guidelines: Sugarbeets

(Reviewed January 2024; No changes)

Cercospora beticola
  1. Apply QoI fungicides according to manufacturer’s recommendations for the target disease (or complex) at the specific crop growth stages indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations. 
  2. QoI fungicides must be applied only in mixture with partners from a different cross-resistance group, contributing to the effective control of the target pathogens. 
  3. Apply QoI fungicides preventatively. Under high disease pressure the spray interval should not be extended. 
  4. The maximum number of QoI-containing sprays is 3, but only when QoI fungicides belonging to both QoI Groups (code 11 and 11A) are included in a spray program. QoI fungicides belonging to the individual Codes (11 or 11A) should not be applied more than 2 times either individually or when mixed together. 
  5. Do not exceed 50% of the total number of sprays with QoI containing products. In low disease pressure situations where only one fungicide application is required for disease control, then a QoI – containing mixture (as defined above) may be used. In areas where ‘exactly’ three applications are expected, a maximum of one QoI 11 and a maximum of two QoI 11A may be applied so long as not more than two QoI applications are made in total.

Where QoI fungicides are used targeting other sugar beet diseases (e.g. rust, powdery mildew, Rhizoctonia, Ramularia and Stemphylium), then the potential impact of applications on the resistance management of Cercospora beticola should be considered. Where Cercospora beticola is not a disease of importance (e.g. in a certain geography) then the general guidelines for QoI fungicides apply.

QoI Guidelines: Cucurbits

(Reviewed January 2024; No changes)

  1. Apply QoI fungicides according to manufacturers' recommendations for the target disease (or complex) at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations.
  2. Apply a maximum of 3 QoI fungicide sprays per crop.
  3. Use a maximum of 1 QoI fungicide spray out of every three fungicide applications.
  4. Do not use consecutive applications of QoI fungicides.
  5. Apply QoI fungicides in alternation with fungicides from a different cross-resistance group with satisfactory efficacy against the targeted pathogen(s).
  6. Continue QoI fungicide alternation between successive crops.

QoI Guidelines: Greenhouse grown non-cucurbit vegetables

(Reviewed January 2024; No changes)

  1. Apply QoI fungicides according to manufacturers' recommendations for the target disease (or complex) at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations.
  2. Use a maximum of 1 QoI fungicide spray out of every 3 fungicide applications.
  3. Do not use consecutive applications of QoI fungicides.
  4. Apply QoI fungicides in alternation with fungicides from a different cross-resistance group with satisfactory efficacy against the targeted pathogen(s).
  5. Continue QoI fungicide alternation between successive crops.

QoI Guidelines: multiple spray crops (non-cucurbit field vegetables and ornamentals)

(Reviewed January 2024; No changes)

  1. Apply QoI fungicides according to manufacturers recommendations for the target disease (or complex) at the specific crop growth stage indicated. Effective disease management is a critical parameter in delaying the build up of resistant pathogen populations.
  2. Observe spray limitations in the spray guideline table shown below for programs utilizing 12 or fewer fungicide sprays per crop.

Spray guideline table:

Total number of spray applications per crop

1

2

3

4

5

6

7

8

9

10

11

12

>12

Maximum recommended solo QoI fungicide sprays

1

1**

2**

2

2

2

2

3

3

3

3

4

*

Max. recommended QoI fungicide sprays in mixture

1

2

2

2

2

3

3

4

4

5

5

6

*

Table Footnotes:
* When more than 12 fungicide applications are made, observe the following guidelines:

  • When using a QoI fungicide as a solo product, the number of applications should be no more than 1/3 (33%) of the total number of fungicide applications per season.
  • For QoI mixes in programs in which tank mixes or premixes of QoI with mixing partners of a different mode of action are utilized, the number of QoI containing applications should be no more than ½ (50%) of the total number of fungicide application per season.
  • In programs in which applications of QoI are made with both solo products and mixtures, the number of QoI containing applications should be no more than ½ (50%) of the total number of fungicide applied per season.
** Mixtures are preferred

For a printer friendly version of these use recommendations see section 2.2.2.7, 2.2.2.8, and 2.2.2.9 of the latest "Minutes of the QoI Working Group Meeting" below.

QoI Guidelines: Rice

(Reviewed January 2024; No changes)

Rice Blast (Pyricularia oryzae, Magnaporthe oryzae)
  1. Apply a maximum of 2 foliar treatments per season.
  2. Use QoI fungicides only in mixtures with non-cross resistant fungicides. At the chosen rate, the respective partner(s) on its/ their own has/ have to provide effective disease control. Refer to manufacturers recommendations for rates.
  3. Apply QoI fungicides in programs with fungicides of different modes of action.
  4. Although QoI fungicides for seed production should be avoided, the very limited amount of different modes of action available for rice blast control could justify QoI uses (in mixtures) only in areas without confirmed QoI resistance. 
  5. Apply QoI fungicide based products at effective rates and intervals according to manufactures’ recommendations. 
  6. To keep good field sanitation, avoid transplanting diseased seedlings, remove or destroy primary infection source e.g. left-over seedlings, infested straw and chaff.

Seedling box, paddy granule or seed treatment applications in Rice
QoIs are and will be used as seedling box, paddy granule or seed treatment products.

It is FRAC’s objective to protect this fungicide group and integrate all uses into technical recommendations. These minutes contain a recommendation on seed treatments, including those which have efficacy on foliar pathogens.

These recommendations will be reviewed regularly and supported by monitoring.

  1. When a QoI fungicide is used as seedling box, paddy granule or seed treatment on rice, there should be no implications regarding QoI FRAC guidelines on the use of foliar QoI fungicides on the same crop as long as the QoI seed treatment is directed by rate and efficacy against seed and soil borne diseases or ‘low risk’ foliar pathogens. (Link to FRAC pathogen risk classes)
  2. QoIs used as seedling box, paddy granule or seed treatment in rice providing foliar efficacy against pathogens with moderate/ high resistance risk count against the total number of QoI applications.
  3. If QoI seedling box, paddy granule or seed treatment with foliar efficacy has been used, first foliar application have to be made with a different mode of action in the vegetative phase before subsequent QoI-based foliar sprays in the reproductive phase.
  4. Please refer to the recommendations of Japan-FRAC.

For a printer friendly version of these use recommendations see section 2.2.2.10 of the latest "Minutes of the QoI Working Group Meeting" below.

QoI Guidelines: Banana

Please refer to the recommendations of the banana FRAC working group: The conclusions and guidelines of the meetings of the FRAC Banana Working Group are available on the FRAC Website (https://www.frac.info/frac-teams/working-groups/banana-group/recommendations-for-bananas).

QoI Guidelines: Other crops and pathogens

Crops and pathogens not covered above with a specific recommendation, follow the general guidelines.

 

Monitoring Results and Recommendations

At the annual meeting, the working group reviews the current year's monitoring results and decides whether they require changes be made to the next year's use recommendations.  The minutes of those meetings are below.

Contact

Helge Sierotzki
Chair

Syngenta Crop Protection Münchwilen AG 
WST540.1.94 
CH-4332 Stein

Tel : +41 62 866 01 80 
Fax: +41 62 866 07 63

E-Mail: Helge Sierotzki