AgreGuard™-1 Silver Overview
Innovotech has developed a unique antimicrobial product for crop protection, AgreGuard™-1 antimicrobial silver, which demonstrates unique efficacy against both bacterial and fungal infestations. This antimicrobial for crop protection is cost-competitive, due to a simple manufacturing method with high purity and yield, and has a low environmental impact. This is due in part to the low quantities of material required for efficacy (in some cases the quantity of silver on treated seed is less than naturally occurring levels of silver in soil), the fact that accumulation/residue has not been detected in plant tissues post-application, and the fact that there is a low risk of microbial resistance developing to the product.
AgreGuard™-1 antimicrobial silver has demonstrated efficacy both in in vitro pulse crop seed coating assays and in greenhouse and field trials as a foliar spray, with no observed negative effect on germination, emergence, or vigour at effective antimicrobial doses.
AgreGuard™-1 antimicrobial silver is able to eliminate a broad spectrum of bacteria and fungi in both planktonic and biofilm forms. It may be key to providing an effective and environmentally friendly replacement for banned antibiotics such as streptomycin in a variety of agricultural applications.
Note: AgreGuard™-1 is not registered with any regulatory agencies at this time.
AgreGuard™-1 antimicrobial silver is a new type of silver(I) antimicrobial compound. Physicochemical characterization of the material has demonstrated the following:
- Slow/sustained release properties
- Small grain size (nanoscale, with particle sizes on the microscale) combined with polycrystallinity and a large surface area for increased activity
- Good stability in water, gels, and a variety of solvents
- Shelf life in powder form >2 years at room temperature
In Vitro Testing
AgreGuard™-1 antimicrobial silver in vitro testing has demonstrated:
- Multiple mechanisms of action
- Ability to penetrate and disrupt mature biofilms
- Anti-adherence activity (ability to prevent biofilm formation)
- Rapid anti-planktonic activity
- Broad-spectrum activity against Gram-positive bacteria, Gram-negative bacteria, and fungi
- Antimicrobial efficacy against agricultural pathogens such as Pseudomonas syringae syringae, Pseudomonas syringae pv. phaseolicola, and Curtobacterium flaccumfaciens pv. flaccumfaciens
Greenhouse and Field Trials
- AgreGuard™-1 antimicrobial silver has been included in greenhouse and field trials for foliar applications to control bacterial spot, speck, and canker in tomato and pepper as part of an IR-4 project and was identified as one of the top performing products tested (as an example, see linked publication, which discusses effectiveness against bacterial spot of tomato – BST – caused by Xanthomonas spp.)
- AgreGuard™-1 foliar treatment was effective against fire blight (Erwinia amylovora) in apples