An adjuvant enhances the performance of pesticides and is divided into two categories: activator and utility adjuvants. Activator adjuvants, like surfactants and oils, improve pesticide activity, while utility adjuvants serve various specialized roles. Sticker adjuvants, a subset of utility adjuvants, are crucial in combatting pesticide resistance and sustaining effective fungicide application. By prolonging fungicide adhesion to leaf surfaces, sticker adjuvants reduce the need for frequent applications, promoting sustainability.
The biopesticide market, set to grow to $8 billion by 2025, relies heavily on sticker adjuvants, particularly for biofungicides. These adjuvants ensure microbial spore germination and growth by maintaining leaf surface retention. Additionally, they offer UV protection and rainfastness, enhancing biopesticide performance. When combined with biopesticides, biobased sticker adjuvants not only boost efficacy and reduce resistance but also contribute to a more sustainable and environmentally friendly approach in crop protection, reducing the impact on soil, water, and air quality.
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.
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).
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).
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.
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.
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 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 adjuvant added product.
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.
Reference and Author– Team Ingevity
