Promalin® Helps Shape Success for Apple Growers

Ideal for application on apples.

Offered in a stable, liquid formulation that is easy to measure and apply in the field, Promalin® offers numerous benefits for apples, including:

  • Improved fruit shape (typiness) and size of varieties such as Red Delicious and Gala
  • Enhanced fruit finish (russet control)
  • PromalinIncreased fruit set after a frost event
  • Increased branching in nursery trees and newly planted orchards

How Promalin Changed the Game
In the 1960s, the introduction of GA3 and ProGibb® ushered in a revolutionary new era of commercial fruit production. The impact and success of ProGibb in both the grape and citrus industries spawned exciting new opportunities and production possibilities for plant growth regulators (PGRs) in general and fruit growers specifically.

By the early 1970s, the Agricultural Products Division of Abbott Laboratories (now Valent BioSciences) was firmly established as the global leader in PGR development and manufacturing. The company’s dedication to GA3 strain and fermentation process improvements yielded higher-quality and more affordable GA3 than was ever before possible. The transformation was so dramatic that many other GA3 manufacturers elected to exit the market entirely, solidifying the company’s position as the industry leader and innovator.

At that time, the organization made the strategic and farsighted decision to leverage its newfound expertise and its proprietary, pharmaceutical-grade manufacturing process by identifying new ways it could help growers meet production challenges. While more than 100 different gibberellins were identified by researchers, only three of them (GA3, GA4, and GA7) showed commercial promise at the time.

Enhancing the Top Variety
At the top of the list for game-changing opportunities was the unmet need facing the apple industry, particularly production of the world’s top-selling variety, Red Delicious, which dominated global apple production in the mid-1970s. These apples are characterized by “typiness,” the elongated shape and prominent calyx lobes for which the variety is known. In Red Delicious apples, typiness is the key quality indicator. Consumer preferences dictate that the more “typy” the Red Delicious, the better.

The challenge with Red Delicious was that without cool nights during bloom, typiness (and fruit grade) would lag. Not only did this challenge affect apple production when atypical climatic conditions occurred, but it compromised crop quality in major apple-growing regions such as Asia, South Africa, and Australia, where cold winters and cool nights during bloom were less frequent.

When it was confirmed that GA4+GA7 and the cytokinin 6-Benzyladenine (6-BA) each had a positive effect on size and typiness, and that the effect was more pronounced when the two compounds were used in combination, developing a new PGR product for Red Delicious producers became a top priority.

Registration and Additional Benefits
The first registration for Promalin was granted in the U.S. in 1978, and in the ensuing years, Promalin became widely adopted around the world, changing the game for apple growers in every major apple-producing region.

Developed initially to promote typiness on Red Delicious apples, Promalin was found to provide additional benefits such as russet control, increased fruit set, fruit size, and branching promotion in all apple varieties that proved to be significant for a grower’s bottom line. Multi-year studies confirmed that the product increased apple yield by 6% on average and increased packout by shifting size categories by one-half to one size, which translated into incremental gross income for growers.

Most recently, Valent BioSciences confirmed that additional size benefits result when Promalin is used in a program with MaxCel® on hard-to-size cultivars, further maximizing profitability for growers.

Valent BioSciences continues to work diligently to promote and strengthen the Promalin brand. Since the first registration, the company has developed and registered Promalin around the world, enabling growers in all major apple-growing regions to benefit from this game-changing technology and establishing Promalin as a global powerhouse brand.