Ingevity’s novel sticker adjuvant technology improves biological formulation efficacy

An adjuvant is a substance added to a pesticide product or pesticide spray mix that enhances the pesticide’s performance. ¹ The global adjuvants market is approximately $3.3B and is expected to grow at a 5.5% CAGR.² Within the adjuvant market, there are two subclasses of products – activator adjuvants and utility adjuvants. Activator adjuvants include surfactants, oils, or nitrogen-based fertilizers that help improve pesticide activity by reducing surface tension or increasing the absorption rate through the leaf surface. Utility adjuvants optimize pesticide performance through a wide range of special purpose roles such as conditioning agent, defoaming agent, tank mix compatibility agent, drift reduction agent, or sticking/rainfastness. ¹

There is continuous need for sticker adjuvants in the market, primarily to combat resistance issues and to differentiate fungicide products in a very generic market.³ Sticker adjuvants represent a small portion of the adjuvants market but play a major role in pesticide resistance management and sustainable practices, especially with contact fungicides. A contact fungicide is applied to the leaf surface, and a sticker adjuvant ensures fungicide stays on the leaf surface for an extended period, which will allow the active ingredient to prevent fungal spore germination. There is lots of market information showing that the use of sticker adjuvants provides increased efficacy of fungicides by keeping them on the leaf surface longer and reducing infection. This results in a more sustainable practice as fewer fungicide applications are needed.

The global biopesticide market represents about 5% of the global crop protection market and is expected to grow to $8B by 2025.⁴ There will be a continued need for sticker adjuvants for biological formulations as biofungicides represent the majority of the biopesticide market.⁴ Microbial-based biofungicides need to stay on the leaf surface to allow for microbial spore germination. At that time, they are exposed to rain, sun, and other atmospheric conditions. Through good rainfastness, sticker adjuvants can support leaf retention of the spores, allowing enough time for their germination and multiplication of microbial in biopesticide. There is further enhancement of biopesticide performance when adjuvant provides UV protection in addition to rainfastness, allowing microbial spores for even better colonization of the leaf surface. Especially biobased sticker adjuvants, when used together with biopesticides, not only enhance performance, and reduce resistance, but also provide an overall sustainable approach for the crop protection with fewer application rounds and much lower soil, water, and air impact.

Ingevity recently launched a new sticker adjuvant product line, AltaHance™, providing excellent and tunable rainfastness to agriculture formulations. Rooting from pine-based chemistry for over 80 years of history, AltaHance™ products, with a low CO₂ footprint, contain >99% biogenic carbon and are readily biodegradable. The unique ability of AltaHance™ technology offers tunable rainfastness with some additional spreading benefits and potential UV protection, making it a truly multifunctional adjuvant product line. It has been proven to work well with fungicides, herbicides, insecticides, and with all kinds of formulation types, including SC, WDG, WP, SL, EC, OD, CS, SE, micronutrients, etc. More details of AltaHance™ S, 2S and 3S with conventional chemical formulations can be found in a previous article published in AgroPages Ingevity: Biobased Adjuvants — The Future of Sustainable Agriculture-Agricultural news.

For biological products formulations, we recommend using AltaHance™ S, based on the safety data for microbial organisms combined with strong performance in-can and in tank-mix.

Table 1. Basic physical/chemical properties of Ingevity’s AltaHance™ S.

* Flash point: closed cup; viscosity: Brookfield, S21 spindle, 25°C, 50rpm; pH: 10% in 1:1 IPA:water; 

Great biocompatibility of AltaHance™ S with microorganisms

To achieve a high and consistent performance of biological pesticides, rainfastness of biological formulations is of great importance as discussed above; however, there are very limited instructions and choices for farmers when applying biological pesticides. One of the biggest concerns is the biocompatibility of the adjuvant product. Ingevity’s adjuvant product, AltaHance™ S, with >99% bio-derived green content, is very safe at a broad range of use rates for a wide range of microorganisms, including gram-positive and gram-negative bacteria and fungi.
   
Minimal to no toxicity to biological organisms at normal use rates:

• Burkholderia cepacian
  

• Rhizobium leguminosarum
  

• Bradyrhizobium japonicum
  

• Bacillus megaterium
  

• Trichoderma reesei
  

• Beauveria bassiana
  

• Bacillus subtilis
  

• Other bacillus strains
  

Excellent rainfastness with AltaHance™ S for biological pesticides in tank mix applications

Beauveria bassiana WP formulation is well known to control arthropod species. However, the rainfastness of the formulation is very poor, close to only 2 % retention after simulated rain test. In a tank-mix with Beauveria bassiana WP, AltaHance™ S improved rainfastness of the formulation by up to 73% at a 1% use rate and 56% at a 0.5% use rate. (Rainfastness evaluation is based on the American Society of Testing and Materials (ASTM) method STP1579 with minor modifications.) Compared to another biobased industry standard, polyterpene-based sticker adjuvant, the rainfastness improved at a low use rate of 0.5% of AltaHance™ S is about five folds of rainfastness versus a 0.5% use rate of polyterpyene sticker. AltaHance™ S outperforms industry standards in a tank-mix application, even at a low use rate of 0.5%.

Sticker/spreader: AltaHance™ S: Castor oil ethoxylate (95:5)
Figure 1. Rainfastness of Beauveria bassiana WP formulation with sticker adjuvants at different use rates in tank mix application.

To improve the effectiveness of Bacillus thuringiensis (B.t.) SC formulation, good rainfastness is highly desired. Our experiment proved that with only a 0.04% addition of AltaHance™ S in tank-mix application, active ingredient retention improved from 2% to over 20% and can be further increased to 33% at a use rate of 0.40%. It also improved the wetting and spreading of the formulation (see figure 2).

Sticker/spreader: AltaHance™ S: Castor oil ethoxylate (95:5)
Figure 2. Rainfastenss of Bacillus thuringiensis (B.t.) formulation with AltaHance™ S sticker/spreader at different use rates in tank mix application.

Excellent rainfastness and biocompatibility with AltaHance™ S for biological pesticides for in-can applications

In-can applications with AltaHance™ S also showed great rainfastness with an increase in retention of up to 43% at a low use rate. Respectively, rates of 2%, 4%, and 8% AltaHance™ S/spreader were added to a commercial B.t. SC product. The study showed continuous rainfastness and enhanced retention over the increasing in-can use rates of AltaHance™ S compared to the commercial product alone (See Figure 3).  It improved the rainfastness from 0% to over 40% retention at a low in-can use rate. At the same time, the survival rate of the B.t. formulation remained the same even at a 10 % in-can use rate after 30 °C storage for 37 days. This is a clear indication showing that AltaHance™ S is very safe for biologicals for in-can and tank-mix applications, even at high use rates (See Figure 4).

Figure 3. Rainfastenss of B.t. formulation with AltaHance™ S sticker/spreader at different use rates for in-can application.

Figure 4. Survival rate of B.t. SC formulation before and after storage at 30 °C for 37 days at 10% AltaHance™ S/spreader in-can use rate comparing to no sticker adjvuant added product.

Potential UV protection of AltaHance™

Biological species are often sensitive to UV exposure, especially the short wavelength UV range. With great UV absorption from AltaHance™ S, by covering biological actives, this adjuvant provides extra UV light protection to the sensitive microorganisms or proteins. At a level of 100 ppm, AltaHance™ S could potentially provide advanced UV protection compared to a polyterpene based adjuvant.

Figure 5. UV transmittance % of AltaHance™ vs polyperpene based sticker at 100 ppm in dichloroethane.

Achieve high bioefficacy for biological products with Ingevity's sustainable adjuvant technology

As the global biologicals market experiences steady growth, demand of enhanced and consistent bioefficacy of biopesticides and biostimulants increases. Ingevity’s biobased and biodegradable green sticker adjuvant, AltaHance™ S, provides great biocompatibility, excellent and tunable rainfastness enhancement for biological formulations. It can be used in both tank mix and in-can applications effectively at very low use rates. AltaHance™ S also provides additional wetting and spreading properties to enhance biological product performance. Ingevity’s high-performing, multifunctional biobased sticker adjuvant allows farmers to gain full benefits from sustainable, high-performing biopesticide and biostimulant products.      

References:

 
1. Spray Adjuvants. (2022, June 30). Penn State Extension. Retrieved December 6, 2022 from https://extension.psu.edu/spray-adjuvants
2. Adjuvants Market. (n.d.) Fortune Business Insights. Retrieved December 6, 2022 from https://www.fortunebusinessinsights.com/industry-reports/agricultural-adjuvants-market-100769
3. Agribusiness Global. (2022 October 4). Industry Insights: Key Themes to Watch in Adjuvants Market Right Now. Agribusiness Global. https://www.agribusinessglobal.com/agrochemicals/adjuvants/industry-insights-key-themes-to-watch-in-the-adjuvants-market-right-now/
4. Global Biopesticides Market. (2020 December 9). S&G Global. Retrieved December 6, 2022 from https://www.spglobal.com/commodityinsights/en/ci/research-analysis/biopesticides-2021.html