How does 1,4-DMN work? What is the mode of action?

1,4-DMN is a dormancy enhancement chemical that, when applied correctly, helps a potato maintain its natural dormancy. 1,4-DMN can also stop further sprout growth on a potato that has started sprouting prior to an application. Unlike CIPC, 1,4-DMN is reversible and does not prevent normal growth once residue levels have dissipated.

How does “dormancy enhancement” work?

Dormancy enhancement acts like a “pause” button for sprouting in potatoes. 1,4-DMN will stop sprout growth above the applicable residue level. Please consult with your applicator regarding any questions about 1,4-DMN residues levels.

What are the application rates? How much do I put on?

Generally speaking, application rates will depend on objective, storage temperature, ventilation, length of time left to store, and variety aggressiveness. As a guideline, the maximum applied rate is 20ppm per application and 80ppm per storage season. The rate most typically used in commercial application is 7-10ppm.

 It is important to consult with your applicator, as rates will vary across North America. Please also consult the product label for further information.

When are these products applied?

Timing is dependent on several factors, including: your individual storage and when the potatoes are moved into the storage, your goals, your crop, and the storage management program you agreed upon with your applicator. Below are some general guidelines:

a. 1,4SIGHT®: Typical programs begin 8-10 days after door closure. However, application can be made as soon as the storage reaches a stable temperature.

b. 1,4SEED®: The United States product label allows for treatment up to 30 days before planting, and the Canadian label allows for treatment up to 60 days before planting.

c. 1,4SHIP®: In transport vehicles when leaving the packing shed. You should plan for a 24- 48 hour transit period.

What is the difference between 1,4SIGHT® and 1,4SEED®?

1,4SEED® is registered for use on seed potatoes, while 1,4SIGHT ® is not.

How is 1,4-DMN different than CIPC?

CIPC is a post-emergence herbicide that disrupts cell division after sprout growth has occurred. CIPC has no activity on the potato until sprout growth commences. 1,4SIGHT® is a dormancy enhancement chemical that helps a potato maintain its natural dormancy.

Does 1,4SIGHT ® affect sugars/color?

Testing has shown that no color shifts occur with 1,4SIGHT®. However, any treatment made with a propane fueled application machine can cause color shifts during the application process, especially during late season treatments.

Does 1,4SIGHT® cause internal sprouts?

No, 1,4SIGHT® will not cause internal sprouts. In fact, 1,4SIGHT® will help eliminate internal sprouting since it stops the growth extension of an active sprout (eye).

Are there are varieties that 1,4SIGHT ® does not work on?

1,4SIGHT® works on all varieties.

Does 1,4SIGHT® affect pressure bruise?

Data suggests that 1,4SIGHT® reduces water loss from stored tubers, and thus also reduces pressure bruising.

When do I take 1,4-DMN residue samples?

1,4-DMN residue samples should be taken 7 days after treatment.

When do I take CIPC residue samples?

CIPC residue samples should be taken 1-2 weeks after treatment and 8 weeks after treatment.

Where can I get 1,4-DMN and CIPC residue sampling done?

DiChlor Laboratory.

At what CIPC residue level should I begin to be concerned?

Please monitor your potatoes to ensure that they do not get near 2ppm or below.

How long have the 1,4-DMN products been used?

In the United States, 1,4-DMN has been registered since 1995, and in Canada it was registered in January 2011.

How many potatoes have been treated with:

a. 1,4SIGHT®? 62,700,000 cwt/year

b. 1,4SEED®? 7,000,000 cwt/year

c. 1,4SHIP®? 4,10,000 cwt/year