US approved new PGR Collate for greenhouse use

Plant growth regulator Collate (ethephon 21.7%) was recently registered in most U.S. states including Michigan and all of the Midwest for greenhouse use, which was developed by Fine Americas, Inc.

For years growers have used the plant growth regulator (PGR) Florel (Southern Agricultural Insecticides, Inc.) on ornamental crops to abort flowers and flower buds, inhibit extension growth, and promote lateral branching. Florel contains the active ingredient ethephon, which releases the plant hormone ethylene. It is labeled for application as a spray, but recent research shows that it can also be effective as a substrate drench. Now, another product that contains the same active ingredient as Florel is available.

Collate, which contains 21.7 percent ethephon, compared with Florel that contains 3.9 percent ethephon. Last year (2012), we compared Collate with Florel as a foliar spray and found that plants responded to the two products similarly. For example, petunia ‘Wave Lavender’ that was treated with two sprays of Collate or Florel at 250 to 750 ppm had similar growth and flowering responses.

Collate was introduced in January 2013, but was not registered for use in Michigan or other states until recently. As of early April, Collate was registered in most U.S. states including Michigan and all of the Midwest.