UNITED STATES ENVIRO:\M ENTAL PROTECTIOS AGESCY

WASHINGTON D.C.. :!0460

JUN 2 4 2010

OffInOf CHEMICAL

SAH.H A~DPOt.lUT10'"

I'REVlNTlOS

MEMORANDUM

SUBJECT:

FROM:

THRU:

Evaluation of Public Interest Findings for the Conditional Registration of

Metrafenone Fungicide for Control of Powdery Mildew Disease on Grapes

(DP # 3783 76 and 378377).

Tara Chandgoyal, Ph. D., Plant Pathologist

Biological Analysis Branch

Biological and Economic Analysis Division (7503P)

Arnet Jones, Chief

Biological Analysis Branch

Biological and Economic Analysis Division (75 3 )

TO: Tawanda Maignan, Risk Manager

Fungicide Branch

Registration Division (7505P)

PRODUCT REVIEW PANEL: June 23, 2010

Summary

The registrant BASF requested a conditional registration of metrafenone fungicide for the control

of powdery mildew disease on grape claiming it is in the public interest. The registrant justifies

its case based on three claims: (I) Metrafenone is a new active ingredient with a new mode of

action against powdery mildew pathogen on grapes, (2) Benefits ofmetrafenone include that it is

effective against powdery mildew (Uncinula necator) and the growers can use it in preventing

and managing resistance deve lopment against established fungicides, and (3) Comparative Risk

shows that it is less risky and has a good environmental and toxicological profil e compared to the

leading/alternative fungicides used for the control of powdery mildew.

BEAD defers to RD, HED and EFED to determine if metrafenone fungicide is more favorable

than other registered fungicides with regard to environm ental and toxicological risks.

A careful review of the submitted public interest finding and available information suggests that

metrafenone is effec tive in controll ing powdery mildew diseases on grapes. The submitted and

available data show that the grape growe rs can effectively control powdery mildew on grape s

using registered alternatives. The grape growers can rotate presently registered fungicides with
different modes of action to prevent/delay the devel opm ent ofresistance in powdery mildew

pathogen. BEAD beli eves that metrafenone is a welcome additional fungicide for the control of

powdery mildew on grapes. However, it does not meet criteria as proposed by the registrant and

considered by BEAD (2, 4, and 6 as given below) for a publ ic interest finding..

Agency Public Interest Finding Pelley

FIFRA section 3(c)(7)(C) authorizes the issuance of a conditional registration for a new pesticid e

with specific restrictions and for a specific period of time. This interim registration allows

temporary use of a pesticide while full registration is being pursued. All three of the following

conditions must be met for a conditional registration: I) insufficient time has elapsed for the

generation of data since the requirement for that data was imposed; 2) use of the pesticide will

not cause unreasonable adverse effects; and 3) use of the pesticide is in the public interest.

The registration of a new pesticide ingredient is presumed to be in the public interest if one or

more ofthe following criteria are applicable: 1) it involves a replacement for another pesticide

that is of continuing risk concern to the Age ncy; 2) it involves a use for which a section 18

emergency exemption has been granted, if the basis for the exemption was the lack of a suitable

alternative; 3) involves a use against a pest of public health significance; 4) There is a need for

the new pesticide that is not being met by currently registered pesticide or non-pesticidal

alternatives; 5) The new pesticide is comparatively less risky than currently registered; or 6) The

benefits from the new pesticide are greater than those from currently registered pesticides or nonchemical pest control measures. BEAD reviewers focus on items 2, 4 and 6.

Metrafenone Fungicide - General Informat ion:

This is a new fungicide and all general information about this fungicide is from the registrant's

submiss ion unless stated otherwise.

The registrant states that metrafenone's mode of action is different than the fungicides registered

for use against grape powdery mildew. It affects several stages in the infection process of

powdery mildew pathogen. The registrant also cla ims that metrafenone inhibits spore

germination, infection of plant tissues, and subsequent myce lial growth. It also reduces

sporulation by preventin g normal development of conidiophores and conidia of powdery mildew

pathogen. Many of these claims have been verified (Opalski et al., 2006). The registrant also

states that this fungicide must be applied be fore visual symptoms of powdery mildew appear. It

does not have curative propertie s and, therefore, it will not control latent or established infections

of powdery mildew. If powdery mildew infections are established metrafenone should be apples

in a tank mix combination with other fungicides or following application of a curative fung icide.

The Fungicide Resistance Action Comm ittee (FRAC) has classified metrafenone fungicide as

belonging to Benzophenone U8 group of fungici des with Unknown Mode of Action

(http://v.w w.frac.into /fracipublicationianhangiFRAC CODE LIST.pdO.

Registrant's Claims in Submitted Public Interest Document:

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The registrant has made several claims in its public interest document. These are:

Registrant's Claim 1: Need Being Met: Powdery mildew pathogen can devastate grape yield

and quality. Metrafenone is a new active ingredient with a new mode of action that makes it a

unique fungicide having fungicidal properties against powdery mildew (Uncinula necator) on

grapes. The registrant has documented the efficacy of metrafenone and some ofthe registered

alternatives in controlling powdery mildew on grapes in 24 tables. The registrant also claimed

that BASF and Interregional Research Project Number 4 (IRA) are developing data for applying

for registrations for use on other crops (such as fruiting vegetables, cucurbit vegetables, pome

fruits and stone fruits) in the United States.

BEAD's Response: At least 20 fungicides are registered for the control of powdery mildew

disease on grapes (applicant's submitted information and

http://npirs.ceris.purduc .cdulhtbi nlpr!ists.com,

https:llpremier.cdms.netlwebapls/results.asp). In this list there are five SBI (sterol biosynthesis

inhibitor) fungicides (fenarimol, myclobutanil, propiconazole, tebuconazole and triflumizole),

four strobilurin fungicides (azoxystrobin, kresoxim-methyl, pyraclostrobin, and trifloxystrobin),

one anilide fungicide (boscalid), one quinoline fungicide (quinoxyfen), one benzimidazole

(thiophanate-methyl), one polyoxin (glucan synthesis inhibitor, polyoxan-D), and many others

(sulfur, mineral oils, petroleum oils, potassium salt of fatty acids, copper-based fungicides,

potassium carbonates, and biological (Bacillus subtilus, and Bacillus pumilus).

The results ofsubmitted and available efficacy data show that most ofthe registered fungicides

(SBI fungicides, strobilurins, boscalid, quinoxyfen and sulfur) are highly effective in contro lling

powdery mildew on grape leaves and fruits (UC-IPM. 2010, Wilcox, 2010; Wilcox and Riegel,

2006 and 2008; Gubler et al. ,2008; Pscheidt, 2009; Scilder et al., 2008 ; Traves et al., 2008). The

different fungicide programs, using a combination ofthese fungicide s, have been recommended

to control powdery mildew on grapes (Gubler et al., 2008). Most ofthe SBI fungicides have

excellent efficacy and consistently control powdery mildew (UC-IPM, 2010). Similarly,

quinoxyfen, Pristine (a mixture of boscalid and pyraclostrobin) and sulfur are highly effective in

controlling powdery mildew of grapes (UC-IPM, 2010, Wilcox and Riegel, 2006). BEAD agrees

with the registrant that metrafenone is a new active ingredient with a new mode of action against

powdery mildew pathogen on grapes. Based on published reports, BEAD concludes that

presently registered alternatives are adequate in contro lling powdery mildew on grapes.

Therefore, it does not meet the Criterion 4 ofthe Agency Public Interest Finding Policy.

Registrant's Claim 2: Benefits: Metrafenone is effective against powdery mildew on grapes

providing control levels better than, or as good as, registered alternative fungicides. Metrafenone

provides a new mode of action that growers can use to prevent and manage resistance

development against established fungicides. Its position in the fungicide market will offer

considerable value for growers.

BEAD's Response: Based on efficacy data submitted by the registrant, BEAD concludes that

metrafenone is as effective as registered fungicides in controlling the disease. On grapes six

different group of fungicides with different modes of action are registered (please see BEAD's

response to claim 1). In addition, copper, sulfur and others are registered for the control of

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powdery mildew. The grape growers have been using different fungicide programs to effectively

control powdery mildew on grapes and manage the development of resistance against registered

fungicides. We agree that metrafenone has a new and unique mode of action against powdery

mildew pathogen on grapes. However, the grape growers have adequate number ofregistered

alternatives to rotate and manage resistance in the pathogen. Therefore, it does not meet the

Criterion 6 of the Agency Public Interest Finding Policy.

Registrant's Claim 3: Comparative Risk: Metrafenone is less risky and has a good

environmental and toxicological profile compared to the leading/alternative fungicides used for

the control of powdery mildew.

BEAD's Response: BEAD defers to RD, liED and EFED to determine if metrafenone fungicide

is more favorable over other registered fungicides with regard to environmental and toxicological

risks as per Criteria 1 and 5 ofthe Agency Public Interest Finding Policy.

Economic Considerations:

The data package submitted by BASF does not have any information on the economics ofthis

fungicide. Generally, in a Public Interest Proposal, economic information includes expected

market price, expected percent share ofthe market and an analysis ofthe primary competitive

products. BASF has provided no information to determine market share or market price to

evaluate its impact on the market.

BEAD Analysis and Conclusions:

From the published report s it appears that powdery mildew can be managed very effectively

using currently registered fungicides. The grape growers can rotate presently registered

fungicides with different modes of action to prevent/delay the development of resistance in the

powdery mildew pathogen. BEAD believes that metrafenone is a welcome additional fungicide

for the control of powdery mildew on grapes. However, it does not meet any criteria evaluated

by BEAD for a public interest finding. BEAD defers to RD with regard to whether metrafenone

fulfills other criteria for a public interest finding.

References:

Gubler, et al. 2008. Grape Powdery mildew. How to Manage Pests - DC Pest Management

Guilelines (htlp://ipm.ucdavis.edu/PMG/r302 l0031 1.html). Accessed June 10, 2010

Opalski, KS., Tresch, S., Kogel, KH., Grossman K., Kohle, H and Huclelhoven, R. 2006.

Metrafenone: studies on the mode of action of a noval cereal powdery mildew fungicide.

Pest Management Science 62(5): 393-401.

Pscheidt, JW. 2009. Grape - Powdery Mildew. An online guide to plant disease control

(http://ipmnet.org/plant-disease/disacase.cfin ?RecordIO- 525). Accessed June 09, 2010

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Scilder, AMC, Gillett, JM and Sysal, RW. 2008. Evaluation offungicide for control of powdery

mildew and downy mildew in wine grape s. Plant Disease Management Reports 4: SMF034.

Travis, JW, Halbrendt, NO and Jarjour. 2008. Eva luation of synthetic and organic alternative

fungic ides for control of powdery mildew on grapes. Plant Disease Management Report s

3: SMF027.

UC-IPM. 20 10. Grape - 2010 Fungicide Efficacy and Treatment Timing

(http://ipm.ucdavis.edu/PMG/r302902 11I.hlml). Accessed June 14, 2010

Wilcox, WF. Strategies to control powdery mildew.

(http://wv..W.practicalwincry.com/marapr03/marapr03p16.htm ). Accessed June 10, 2010

Wilcox, WF and Riegel, DG. 2006. Evaluation of fungicide programs for control of powdery

mildew on Concord grapes. Plant Disease Management Reports 1: SMF006.

Wilcox, WF and Riegel, DO. 2008 . Evaluation of fungicide programs for control of powdery

mildew on Chardonnay grapes. Plant Disease Management Reports 4: SMF046.

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