Quash®

Fungicide

Highbush and Lowbush Blueberry

Technical Manual

Innovative solutions. Business made easy.

Aim:To control mummy berry, anthracnose ripe rot, phomopsis twig blight and fruit rot and protect yields in highbush and lowbush blueberries.

Introduction:Blueberry growers can now use Quash® as part of an Integrated Pest Management (IPM) program for the control of many important diseases.

Quash offers blueberry growers broad spectrum disease control at a low single application rate.

The fungicide belongs to the sterol biosynthsis inhibitor (SBI) fungicides, which constitute the Fungicide Resistance Action Committee (FRAC) - Group 3. Quash is a WDG formulation containing the active ingredient metconazole, 50%.

Benefits of Using Quash:• Broad spectrum disease control – labeled for many important diseases,

including mummy berry and more.

• Flexible application timing starting at green tip though bloom.

• Highly active – controls many diseases with one low use rate.

• Short pre-harvest interval (PHI) – shorter PHI than other products in-class.

• Effective against pathogens during infection and extending through sporulation.

• Penetrates the plant cuticle (outer plant layer) and translocates out from the point of contact.

• Gives good residual activity and movement from the point of application in the plant and outward.

• Chemically stable over a wide range of pH and temperature.

• Presents a low risk to beneficial insects, such as honey bees.

• Does not require a surfactant/adjuvant. In the cases where Quash has been carefully evaluated, increased or decreased efficacy from the addition of surfactants was not found.

3

Understanding Mummy Berry (Monolinia Blight):Mummy berry is one of the most serious and devastating diseases of blueberries. The fungus can reduce yields and lead to big losses. If left unmanaged, it causes infected leaves and flowers to wilt and turn brown, potentially leaving almost half the berries to be lost.

The fungus overwinters in berries left from the previous season. In the spring after the fungus has spread, white spore masses are visible on leaf shoots and the base of flowers. Entire flower clusters are usually affected. Affected fruit turns grey in colour, becomes mummified and falls off. There are two stages of infection occurring from bud break until shoots are approximately 3 inches long.

Blueberry infected with Monolinia Blight. Photo provided by ES Cropconsult

Mummyberrydisease cycle

1. When blueberry buds start to open the mummies produce cups which contain many spores. These get shot in the air and land on opening buds.

2. Fungicide sprays protect the young buds at this stage.

3. Primary infection When the spores from the mum-

mies infect young leaf and flower buds it is called the “primary infection.

4. Infected flower and leaf buds become infected flower and leaf

clusters. The fungus then produces another type of spore at the base of the cluster. Insects and splashing rain carry these spores to the open flowers.

5. Secondary infection Spores infect the open flowers.

As the fruit ripens, it turns salmon-coloured and drops to the ground.

6. Mummies that have dropped to the ground rest there over the winter.

1

2

3 4

5

6

5

Understanding Anthracnose Ripe Rot (Colletotrichum Acutatum)Anthracnose, or ripe rot, is a very serious fungus that infects leaves, twigs, canes, blossoms, fruit and leaves (pre and post harvest).

The disease can cause various symptoms in blueberry plants, which result in loss of yield and the transfer of infection to ripening fruit. The fruit rot manifests itself as sunken areas at the end of the ripe fruit, which then shrivels over time. Pink wet spore masses can be noticed on the shriveled fruit over time. The spore masses then spread to other berries by rain or irrigation through splashing water and contact during harvest, resulting in substantial pre- and post -harvest losses.

The fungus overwinters in infected twigs, old fruiting spurs and live buds. In spring and summer, spores produced on infected tissues are dispersed by rain and cause new infections. Infection usually occurs between bloom and early fruit development. Prolonged wetness (12 hours or more) and temperatures of 20 -25°C promote disease development. Fruit infections remain latent until the fruit starts to ripen or until after harvest.

Anthracnose. Photo provided by BC Ministry of Agriculture

Ripe Rot Disease Cycle

Early Spring: Infected flower buds are usually elongated, larger and more red in colour than healthy buds.

4-7 laterals develop from each infected bud on floricanes, resulting in witches’ brooms. This is the most obvious symptom of rosette.

Spring: Fungus sporulates on pistils and stamens of infected flowers and condidia infect primocanes.

Summer: No fruit grows on infected primocanes.

These primocanes grow with no other symptoms.

Mycelium grows within lateral bud, filling the spaces between embryonic bud elements.

Late Summer: Fruiting canes die. Primocanes continue to grow.

Late Fall - Winter: Bud proliferation is induced in infected buds.

Anthracnose disease cycle. Disease cycle of Raspberry Anthracnose. Adapted from the Compendium of Raspberry and Blackberry Disease and Insects of the American Phytopatholical Society.

7

Quash®

FungicideWhen to apply?Apply Quash when conditions favor disease development and prior to infection. Quash can be applied from green tip through to bloom stage depending on the targeted pests.

Mode of Action:The active ingredient in Quash is metconazole, a DMI (DeMethylation Inhibitors) or Sterol Biosynthesis Inhibiting (SBIs) broad spectrum fungicide belonging to the Group 3 fungicides.

Quash works by inhibiting the biosynthesis of ergosterol, which is a major component needed for fungal growth. Metconazole is a systemic fungicide that is absorbed quickly into the plant tissue and can move out from the treated area in the plant. Metconazole has no effect on fungal spore germination, but inter-feres with other early developmental processes in the life cycle of certain fungi. Although Quash cannot prevent spore germination, it prevents spore formation and inhibits mycelial growth.

Quash is most effective when applied prior to infection. Quash works as a preventative fungicide with SOME curative action. Quash will move in leaf tissue from point of contact out. It does not move out of a treated leaf to other leaves above or below (not phloem mobile) or from root to top or top to roots. Coverage is extremely important for optimal protection. If an application is made curatively, it must occur during the incubation period. After symptoms develop, curative activity is compromised. The incubation period varies from disease to disease and the duration is influenced by temperature, moisture, host resistance, inoculum concentration and other factors. Under optimal conditions, this period can be as short as 4 days.

Optimal disease control is achieved when Quash is applied in a regularly scheduled spray program and used in combination and/or rotation with other effective fungicides that have different modes of action (i.e., non-Group 3 fungicides). Quash is a sterol biosynthesis inhibitor; avoid rotating with other sterol biosynthesis inhibitors.

Quash is not volatile and is not mobile in soil.

8

Quash is loco systemic = xylem movement within treated leaf

Apical bud(terminal bud)

Petiole

Blade

Apply here

Apply here

Translocatesoutward within leaf

Leaf

Shoot system

Rootsystem

Node

Node

Internode

Lateral root

Stem

Primary root

Auxillary bud

Quash is Translaminar − Moves through the leaf.

9

Rate of Application:Apply Quash at 180 g/ha or 73 g/ac in highbush and lowbush blueberries.

Formulation of Quash:Quash is a water dispersible granular. It comes in a water soluble package. The active ingredient is metconazole 50%. It has excellent suspension and is easy to handle.

The Program:Quash can be used alone for the control of labeled diseases, however, it is recommended Quash be used as part of an Integrated Pest Management (Program IPM).

Triazoles, as well as all DMI fungicides (including Quash), are considered to be at medium risk for resistance development. It is generally wise to accept that cross resistance is present among all DMI fungicides active against the same fungus. Therefore, it’s important not to use Quash, or any other DMI, in situations where DMI-resistant pathogens already exist.

Water Rates:Coverage is important to receive good efficacy. Make sure water volume is suffi-cient to obtain coverage of blossoms, foliage and fruit. A minimum of 200 L/ha water volume is recommended.

Quality WDG formulation – granule structure accelerates water uptake

and dispersion

One pouch of Quash comes in two 280 gram water soluble packages for

easy handling.

Resistance Risks Pathogens in Blueberries:• Life cycle of the pathogen – the shorter the generation time, the more

frequent the need for exposure to the fungicide and the faster the build-up of resistance.

• Abundance of sporulation – the more spores that are released in the crop the greater the availability of individual genomes for mutation and selection, and the faster the spread of resistant mutants.

• Ability of spores to spread between plants, crops and regions.

• Ability to infect at all crop stages, requiring repeated fungicide treatment.

• Occurrence of a sexual stage in the life cycle; this could either favor or hinder resistance development.

• Ability to mutate or to express mutant genes: certain pathogens seem to produce fit mutants more readily than others; diploidy may suppress expression of recessive mutations; gene structure may render mutations lethal.

Resistance Management:FRAC has made the following general recommendations regarding use of SBI fungicides (including triazoles):

• Do not use repeated applications of SBIs alone on the same crop in one season against a high-risk pathogen in areas of high disease pressure for that pathogen.

• For crop/pathogen situations requiring multiple spray applications, e.g. orchard crops/powdery mildews, use mixtures or alternate (in block sprays or in sequence) with effective non-cross resistant fungicides.

• If mixture or alternation is not possible, reserve SBI use for the critical part of the season or critical crop growth stage.

• If DMI performance declines and less sensitive forms of the pathogen are detected, they should only be used in mixture or alternation with effective non-cross-resistant fungicides.

• Complementary use of other fungicide classes with different modes of action should be maximized.

• Use as recommended on the label. Do not use reduced doses.

• Use other measures such as resistant varieties, good agronomic practice and plant hygiene.

Mixing Instructions:

1. Fill clean spray tank 1/2 to 2/3 of desired level with clean water.

2. While agitating, slowly add the Quash to the spray tank. Agitation should create a rippling or rolling action on the water surface.

3. If tank mixing Quash with other labeled pesticides, add water soluble packets first, followed by dry formulations, flowables, emulsifiable concentrates and then solutions.

4. Add any required adjuvants.

5. Fill spray tank to desired level with water. Agitation should continue until all spray solution has been applied.

6. Mix only the amount of spray solution that can be applied the day of mixing. Apply Quash within 24 hours of mixing.

Compatibility:Quash has been tested under a wide variety of conditions and in tank mixes with many different fungicides, insecticides and surfactants. While it is impossible to test all the different potential tank mixes of agrichemicals, no incompatibilities are known at this time.

Trial Data:

Storage:Store in the closed, original container in a cool, dry, secure place. DO NOT store for prolonged periods in direct sunlight. For information on disposal of unused, unwanted product, contact the manufacturer or the provincial regulatory agency. Contact the manufacturer and the provincial regulatory agency in case of a spill, and for clean-up of spills.

Do not contaminate water, food or feed by storage. Keep pesticide in original container. Do not put formulation or dilute spray solution into food or drink containers. Do not store or transport near feed or food. Not for use or storage in or around the home. To prevent contamination, store this product away from food or feed.

Re-entry Period, PHI, Rainfastness:The re-entry interval (REI) is: 12 hours.

The pre-harvest interval (PHI) is: 7 days for lowbush blueberry and 12 days for highbush blueberry.

Quash is rainfast 2 hours after application. If there is heavy rainfall before the spray deposit has dried (typically one or two hours after application) you should consider re-applying in order to guarantee high levels of control and long lasting protection from Quash.

0.3

14

23

56

61

0 20 40 60

Quash 175g/ha

Pristine 1.68L/ha

Indar 0.44L/ha

Topas 0.44L/ha

Untreated

80 100

Mummy Berry in Highbush Blueberry

% Fruit Infection Research conducted

Oregon State University 2011

0

20

40

60

80

100

120

Anthracnose in Highbush Blueberry

Untreated

% C

on

tro

l

Quash (280 g/ha) Quash (560 g/ha) Pristine (1.3 kg/ha)

Investigator: J.W. Scheidt and J.P. BassinettSite: Corvallis, ORDate Assessed: 30/07/06

0

20

40

60

80

100

120

Mummy Berry in Lowbush Blueberry

Untreated

% C

on

tro

l

Quash (180 g/ha) Topas (500 g/ha)Investigator: H. PeillSite: Rawdon, NSDate Assessed: 30/05/06

13

Guard against mummy berry, phomopsis and anthracnose. Include Quash in your Integrated Pest Managment program.

14

Notes:

15

Nufarm is the marketer of Valent products in Canada. To learn more about Quash® or any other Nufarm products visit our website or

call our technical support line, toll-free.

www.nufarm.ca1-800-868-5444

This information is for marketing purposes only. ALWAYS READ AND FOLLOW THE LABEL BEFORE USING ANY NUFARM PRODUCTS. Quash® is a registered trademark of Valent U.S.A. Corporation. Indar® is a registered trademark of Dow AgroSiences LLC.

Pristine® is a registered trademark of BASF. Topas® is a registered trademark of Syngenta. January 2014