INSIDERSPotato Growth Regulators and Sprout Inhibitors1,4DMN: the key to stabilized dormancy and uniform emergence in seed potatoes

    1,4DMN: the key to stabilized dormancy and uniform emergence in seed potatoes


    Due to the heat/cold/wet stress many potatoes endured during last fall’s harvest, a lot of stored potatoes are likely to be pushing sprouts sooner than usual this year. While processing and table stock growers have several sprout suppressing options, seed potato growers have exactly one product available to enhance dormancy. Luckily, it’s an effective one.

    1,4 Seed is the only registered dormancy enhancer available for use in seed potatoes. It is formulated from 1,4 Dimethylnapthalene (1,4DMN), a naturally occurring potato hormone that stabilizes dormancy but allows tubers to resume growing once it volatilizes. 1,4DMN works effectively even in potatoes that are partially warmed during shipping.

    1,4DMN’s dormancy enhancement allows tubers to store their energy rather than expending it through early sprouting, which translates to higher seed vigour once seeds are planted. In addition, a reduction in sprouting corresponds to less shrink and more salable weight for seed producers.

    1,4DMN also benefits potato growers by breaking tubers’ apical dominance in certain varieties (of the 17 varieties we’ve tested, it successfully broke apical dominance in all but one). By stimulating more even growth of all eyes, 1,4DMN results in more uniform emergence across a field, which allows a farmer to optimize management throughout the season, ultimately producing a healthier, stronger, higher-producing crop. Managed correctly, tubers treated with 1,4DMN can offer better and more even tuber set with more stems per plant in most varieties.

    Despite 1,4DMN’s proven benefits, some seed growers continue to hesitate to try 1,4 Seed. Rather than recognizing it as a dormancy enhancer, they incorrectly assume it must be a sprout inhibitor (illegal in Canada on seed potatoes). Interestingly, even CFIA initially had concerns that 1,4 Seed might be a sprout inhibitor, but they’ve since come around to recognizing and supporting its use. Farmers, too, are increasingly understanding how 1,4 Seed works. Once they try it, most never go back to racking their tubers, recognizing that relying on the manual removal of sprouts not only uses up a significant amount of each tuber’s vigour, it is also unnecessarily time consuming.

    1,4 Seed is the only dormancy enabling product for use in seed potatoes available anywhere in the world. It has proven its value in Canada since its launch seven years ago, and in the US for more than double that long. With winters tending to be warmer than they used to be and springs often coming sooner, it’s likely more and more Canadian farmers will come to depend on 1,4 Seed.

    Bill Orr
    Bill Orr
    Canada Technical Representative, One Four Group - Bill Orr started in the sprout inhibitor application industry quite by accident. After college, he worked for a tree care company and sprout inhibitor applications were its fall area of business. This was before the VFD was introduced into the application process in Canada. After enduring those dirty times cleaning up after applications, Orr continued on for another 14 years in the industry. He quickly moved on to doing applications, then technical training for applicators, next to managing the entire application process, and eventually to owning his own sprout inhibitor application company. His application experience has allowed him to do application in Alberta, Saskatchewan, and Manitoba. Orr finds sprout inhibiting a very interesting and unique industry, and he enjoys all the dynamics and challenges it has to offer.