Project Number: 8072-12000-014-003-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jun 1, 2021
End Date: Aug 28, 2022
Determine the impact of arbuscular mycorrhizal fungi inoculation on phytonutrient content of potatoes. The impact of arbuscular mycorrhizal fungi on phytonutrient content of potatoes has not been thoroughly evaluated, although a few studies on other crops have found favorable increases in antioxidant activity and concentrations of specific phenolic compounds. This project will investigate the impact of mycorrhizal colonization status on the antioxidant activity of potato tubers, as well as the concentration of selected antioxidant compounds, vitamins, and carbohydrates.
Potatoes will be grown on raised benches in 9-gallon grow-bags filled with a sterilized mixture of soil, compost, and perlite (3:1:1), amended with 5,000 spores per bag of different arbuscular mycorrhizal fungi spores per treatment, or uninoculated controls. The mycorrhizal fungi treatments will consist of Claroideoglomus etunicatum, Funneliformis mosseae, two treatments of Rhizophagus irregularis (one treatment of inoculum produced on farm, one treatment of commercial inoculant), and a mixed-species indigenous population. Two varieties of potatoes will be grown, one yellow (Lehigh) and one purple (Adirondack Blue). Five replications will be tested for each treatment/potato variety pair. Plants watered daily, and fertilized as needed with an organic fish hydrolysate fertilizer. At harvest, the tubers from each grow replication (60 total) will be graded for size and weighed, then washed and dried. Three fresh, medium-sized tubers from each replication will be sent to Purdue University to be freeze-drying and prepared for analysis. The ground tissue will be subsampled for nutrient analysis including sugars, starch and two vitamins (Vitamin C and B6), as well as total antioxidant activity, total phenolics, and anthocyanins (purple variety, only). Total phenolics, anthocyanins, sugars and antioxidant activity of tuber samples will be analyzed using spectrophotometric analyses and vitamins will be analyzed using ultra-performance liquid chromatography (UPLC). Additionally, at flowering, leaf samples (30 total) will be collected, frozen, and shipped to Purdue for the plants of the purple variety for comparative analysis of anthocyanin content in the vegetative portion of the plants.