Purpose: Strawberries are a high-value crop in the United States due to their increasing demand and nutritional benefits. However, strawberry plants are delicate and sensitive to abiotic and biotic factors and prone to gray mold caused by Botrytis cinerea during harvest and post-harvest operations, leading to significant economic losses. Fungicides are effective but raise concerns about residues and the evolution of fungal resistance, limiting their use. Hence, developing alternative approaches is critical for improving the strawberry plant's resilience and solutions to combat gray mold fungus.
Methods: To assess the potassium silicate efficacy on agronomic traits, two strawberry cultivars (Flavorfest and Rutgers ScarletTM) growing under high tunnel conditions were foliar sprayed with different doses (0, 2, 3, and 4mL per gallon of water) in five applications in the fall of 2018 as well as in the spring of 2019. Silica accumulation in the plant samples was determined using Scanning Electron Microscope images coupled with an Energy Dispersive Spectrometer (SEM-EDS) analysis and spectrophotometer method. An in-vitro experiment was used to determine antifungal activity against B. cinerea.
Results: Strawberry leaf samples treated with 2 mL per gallon had higher silica concentrations and phytolith production, which strengthened the aerial parts, reduced translocation to roots, and significantly boosted plant width and marketable yield compared to other treatments. Furthermore, treatment with 2 mL potassium silicate significantly reduced the growth of the B. cinerea.
Conclusion: Our findings suggest that potassium silicate provides potential options to improve the agronomic traits in strawberries and preventative measures against B. cinerea.