An overview of fungicide pre-mixes for tree fruits

Nikki Rothwell<rothwel3@msu.edu>, Michigan State University Extension, and George Sundin, Michigan State University Extension, Department of Plant, Soil and Microbial Sciences - April 16, 2013

Many tree fruit fungicide options are a pre-mixture of two fungicides and growers need to be aware of the components to properly rotate these new materials.

Most of the new fungicides available for tree fruit growers are a mixture of more than one fungicide in the container. These new materials have been pre-mixed and are sold under one trade name. Growers need to be aware of the pre-mixed materials because, in most cases, one of the two materials in the product is not effective due to resistance issues in our common tree fruit pathogens. Growers also need to know the compounds in these products to effectively rotate fungicides to manage resistance, particularly as we have very few compounds available to manage the major tree fruit diseases. Additionally, some of the new products have similar names and may be difficult to decipher for the different crops.

Table 1 contains a summary of the currently available fungicide pre-mixes that can be used to control tree fruit diseases. The table includes the trade name of the product, the common names of both fungicides in that particular product, the mode of action, and the code of each of the fungicides in that product. The group codes were developed by the Fungicide Resistance Action Committee (FRAC) and can be used as a quick way to determine the make-up of each of the pre-mixed products. For example, if a cherry grower uses Merivon (SDHI + stroby: codes 7 + 11) for his or her first cover, another new product, Luna Sensation, is also made up of an SDHI + stroby (codes 7 + 11) and should not be used as a second cover spray as the grower will not be rotating fungicides – the two components of both materials are the same.

Growers should also be aware that all three of the new pre-mixed fungicides, Luna Sensation, Luna Tranquility, and Merivon, and the single mode of action fungicide Fontelis, have a succinate dehydrogenase inhibitor (SDHI) component. This SDHI mode of action has been used in tree fruits since 2004 in the older pre-mixed material Pristine. Data from the Northwest Horticultural Research Center efficacy trials and from cherry leaf spot isolates (CLS) collected from northwest and west central Michigan show that many isolates of the CLS pathogen are less sensitive to the SDHI component of Pristine, and reduced sensitivity is the first stage of a pathogen shifting toward resistance. Fewer isolates have been documented to be resistant to the SDHI component of Pristine. Based on this information, Michigan State University Extension does not recommend growers use Pristine for leaf spot control this season, particularly as we have newer materials that are effective in controlling CLS. The good news from our efficacy trials show that the CLS pathogen is still highly sensitive to the SDHI components of the new materials, Luna Sensation and Merivon, but because these new fungicides share that SDHI component, they must be used with discretion in order to keep these materials for cherry leaf spot control into the future.

Table 1. Summary of pre-mix fungicides available in tree fruits and winegrapes.

Product Name	Fungicide Common Name	Mode of Action	FRAC Code	Fruit Crop
Adament	tebuconazole + trifloxystrobin	SI + stroby	3 + 11	cherries, peaches, nectarines, grapes (not Concord)
CaptEvate	fenhexamid + captan	hydroxynanilide + pthalimide	17 + M4	cherries
InspireSuper	difenoconazole + cyprodinil	SI + anilinopyrimidine	3 + 9	grapes, apples, pears
LunaExperience	fluopyram + tebuconazole	SDHI + SI	7 + 3	winegrapes
LunaSensation	fluopyram + trifloxystrobin	SDHI + stroby	7 + 11	apples, cherries
LunaTranquility	fluopyram + pyrimethanil	SDHI + anilinopyrimidine	7 + 9	apples
Merivon	fluxapyroxad + pyraclostrobin	SDHI + stroby	7 + 11	apples, cherries, pears, nectarines, peaches, plums
Pristine	boscalid + pyraclostrobin	SDHI + stroby	7 + 11	apples, cherries, pears, plums, peaches, nectarines, apricots
Fontelis	penthiopyrad	SDHI	7	apples, cherries, pears, peaches, plums, nectarines, strawberries

This article was published by Michigan State University Extension. For more information, visit https://extension.msu.edu. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464).