Accede® Claims New Ground for Stone Fruit and Apple Growers

Crops
Ideal for thinning peaches, nectarines, and apples

Benefits
The benefits of Accede® include:

  • Fruit thinning on stone fruit and apples
  • Fruit size enhancement

Active Ingredient
Accede contains the naturally occurring compound 1-aminocyclopropane-1-carboxylic acid (ACC), which is rapidly converted to ethylene using the plant’s natural biochemical pathways. Ethylene is a plant hormone with an important role in fruit ripening, as well as leaf, flower, and fruit abscission and senescence.

How Accede Changed the Game
As early as 2005, Valent BioSciences recognized that significant unmet needs remained for crop load management of stone fruit and apples.

While MaxCel® had been successfully launched as an apple thinner in the U.S., there was still a need for a product that effectively thinned apples during the late thinning window, when fruit were larger than 15 mm in diameter.

In stone fruit, many compounds had been evaluated over the years for their thinning activity, but none had achieved commercial success. Stone fruit growers were reliant on increasingly expensive and scarce labor to thin crops such as peaches and nectarines by hand, so that fruit could grow to a size consumers desired.

The launch of Accede in 2021 served to meet both challenges, as Accede was the first apple thinner to provide reliable and predictable activity during the late thinning window, as well as the first product to be registered for thinning stone fruit.

Meeting the Challenge
Some apple growers have been using the synthetic ethylene releasing agent ethephon for thinning for many years, but its effects are unpredictable and may include overthinning in apples, gummosis in stone fruit, and residue problems at harvest.

The active ingredient in Accede, ACC, was first identified as the precursor to ethylene in plants in 1979, but it was never used in commercial practice due to high manufacturing costs. Valent BioSciences began investigating the use of ACC as a thinner in laboratory and field studies in 2005, finding that this compound has several unique advantages over ethephon. ACC is a more reliable apple thinner than ethephon under high-temperature conditions, it does not leave residues at harvest, and application to stone fruit trees does not cause gummosis. In addition, ACC was found to provide thinning activity on apples larger than 15 mm, creating an exciting new possibility for crop load management late in the thinning window.

Unfortunately, for many years, the high cost of manufacturing ACC remained a barrier to its development as a thinning product. The breakthrough arrived in 2016 when Valent BioSciences’ parent company, Sumitomo Chemical Co., Ltd., identified a cost-effective, scalable method for manufacturing ACC.

A New Tool for Stone Fruit Growers
Stone fruit growers worldwide have had to rely almost exclusively on the availability of skilled labor for hand thinning their crop to a commercially acceptable number of fruit per tree that would produce large fruit size at harvest. Hand thinning is usually carried out weeks or even months after flowering. Waiting so long after flowering to reduce the number of fruit per tree places a limitation on the potential fruit size at harvest.

Accede can be applied to peaches and nectarines any time between the pink bud stage and petal fall. The goal of using Accede in stone fruit is to reduce, but not necessarily eliminate, the need for hand thinning. By reducing the number of fruit per tree early in the season, fruit size at harvest is often increased compared to the conventional practice of hand thinning alone.

Valent BioSciences is pleased to have launched Accede as the first stone fruit thinner and late-window apple thinner. As with all of its products, the company is eager to continue driving innovation with this new plant growth regulator and committed to seeking new uses and crops to help further serve growers and fulfill their unmet needs.