Native Arbuscular Mycorrhizal Fungi Enrichment to Improve Water-Use Efficiency, Soil Health, and Berry Yield and Quality in Semi-Arid Vineyards

Commodities

Practices

Texas High Plains vineyards are increasingly constrained by declining groundwater availability, recurring drought, high temperatures, and calcareous and alkaline soils that limit nutrient availability. These conditions reduce vine water-use efficiency, increase fertilizer and irrigation costs, and threaten the long-term productivity and profitability of regional grape production. Native arbuscular mycorrhizal fungi (AMF), already adapted to local soils and conditions, may provide a practical biological tool to improve vine performance under water-limited conditions. However, their field relevance and management value for Southern region grape growers remain insufficiently tested.

This two-year project will evaluate whether enrichment with locally sourced native AMF improves grapevine water relations, nutrient-use efficiency, soil biological function, yield stability and berry quality under well-watered and regulated deficit irrigation conditions. Preliminary greenhouse trials showed that rootstock 1103P responded strongly to native AMF communities collected from High Plains vineyard soils, supporting its selection as the primary rootstock. Year 1 will test mechanisms under controlled greenhouse conditions. Year 2 will validate results at the TTU experimental vineyard in Lubbock, Texas.

Measurements will include vine water status, gas exchange, chlorophyll, canopy growth, leaf and soil nutrients, AMF colonization, root architecture, root-associated microbial communities, yield components, and berry metabolite composition. Grower engagement will include field demonstrations, Extension presentations, factsheets, and short instructional materials. Expected outcomes include practical guidance on whether native AMF enrichment can help growers conserve irrigation water, improve nutrient acquisition, reduce input dependence, and maintain vineyard productivity and fruit quality under drought-prone Southern region conditions.

Objective 1: Determine whether native AMF enrichment improves grapevine water relations, gas exchange, canopy growth, and nutrient status under well-watered and regulated deficit irrigation conditions.

Objective 2: Quantify belowground responses to native AMF enrichment by measuring AMF colonization, root architecture, soil chemical and biological indicators, and root-associated microbial community composition.

Objective 3: Evaluate whether AMF-mediated physiological and belowground responses translate into improved vineyard productivity and berry quality, including yield components and berry metabolite composition.

Objective 4: Develop grower-facing recommendations through field demonstrations, Extension presentations, factsheets, and short instructional materials describing the potential use, limitations, and practical value of native AMF enrichment in Texas High Plains vineyards.