A Field Evaluation of Mycorrhizal Inoculants on Grapevine Growth and Nutrient Uptake

As plant-mycorrhizal interactions are known to be context dependent, a better understanding of the conditions in which mycorrhizal fungi are beneficial to grapevine growth will help to inform vineyard management strategies aimed at incorporating biological inputs and improving agricultural sustainability. In a field experiment at WSU-Irrigated Agricultural Research and Extension Center (IAREC), I propose to test the growth response of two wine grape varieties (Merlot and Chardonnay) to arbuscular mycorrhizal fungi (AMF) under different phosphorous (P) conditions in a randomized complete block design with the following treatments: AMF+P, AMF-P, -P, and +P. Data will be collected on plant growth, leaf and soil nutrients, and mycorrhizal colonization of roots to determine the conditions in which mycorrhizal inoculations are most beneficial to wine grape production. I hypothesize that AMF will improve growth and leaf nutrient content in both grape varieties and that benefits of AMF will be highest in the low P treatment. This proposal addresses BIOAg priorities aimed at developing biologically-intensive management strategies that are renewable, non-polluting, and mutually beneficial to farmers and society. This study will also provide valuable research and training opportunities for a Master’s student at WSU Tri-Cities.