An Adjuvant Designed to Perform with Today’s Pesticides

Most of the insecticides and fungicides developed before 2000 required thorough coverage to be effective.  Spreaders, adjuvants that promote droplet spreading, were formulated with surface tension reducing surfactants to achieve that goal. While those adjuvants performed as designed, the trade-off with reduced surface tension is to flatten the spray droplet, losing some volume off the edges of the leaf due to shatter and gravity pull while increasing the surface area of the liquid that remains on the leaf by creating a very thin coating. Increased surface area accelerates evaporation effectively reducing the time for liquid interface.

Many pesticides used today, however, are systemic or translaminar, having to be absorbed into the plant to be effective. Importantly, pesticide absorption ceases when spray residues have dried.  As spreaders accelerate droplet evaporation, their use with systemic or translaminar pesticides substantially reduces the amount of time for absorption which can limit the ability of the active to function as effectively as it otherwise could. 

Attune set out on a years-long research journey to see if it could develop a different approach to get more spray volume on the leaf and keep it there in a liquid state, an adjuvant without the downsides that come along with the industry’s over-reliance on reducing surface tension. The result of that research is Ampersand, a new adjuvant designed to maximize performance with all pesticides including systemic.

Ampersand achieves maximum coverage without reducing surface tension by increasing adhesive properties to reduce shatter and maintain spray droplet volume on the leaf. With this approach, Ampersand is able to improve upon coverage in 82% of head-to-head comparisons with spreaders. These adhesive properties also greatly improve Ampersand’s ability to keep the spray on the leaf, imparting a 400% increase in wash-off resistance as compared to water and an 84% improvement against latex stickers.  

Because Ampersand does not reduce surface tension, it is able to deliver spray droplets to the leaf that maintain a high contact angle, a bubble shape as opposed to a thin coating. This bubble shape reduces surface area which in turn slows evaporation. We further slow evaporation on the leaf by formulating with humectants to specifically increase the amount of time that systemic pesticides can be absorbed. By reducing surface area and purposefully formulating to slow evaporation, Ampersand is able to double the time for pesticide absorption. 

Ampersand’s higher surface tension and humectants provide additional benefits in that they begin working as soon as a spray droplet leaves the nozzle, reducing fines and the amount of spray droplet evaporation that typically occurs between the nozzle and reaching the plant, allowing more spray volume to reach the plant. The combination of reduced fines and evaporation on the way to the plant, minimizing droplet shatter upon impact and adhering the solution to the leaf while in its original high-volume bubble shape, Ampersand is able to increase deposition up to 300% as compared to current best-in-class spreader/stickers. 

Our research concludes that most of the adjuvants today have not evolved to meet the needs of today’s pesticides. The tank mix is one of the biggest investments a grower makes, not to mention the fact that what is added is there to do an important job to ensure crop performance. It is critical to get the most out of this investment. While Ampersand is formulated with entirely non-toxic food grade materials and is certified organic, it has also been formulated with a data driven approach to address the key needs of today’s pesticides. A step change improvement is possible to achieve the following:

  • 82% of trials deliver better coverage in head-to-head comparisons with gold standard spreaders
  • 400% improved wash-off resistance
  • 300% more deposition than gold standard spreader/stickers
  • 200% more time for pesticide absorption than gold standard spreader/stickers