Rootstock genetic background in almond cultivation influences the composition of root-associated microbial communities and enrichment of taxa associated with plant defense and nutrient availability

Abstract

Beneficial root microorganisms play a crucial role in influencing key agronomic traits in rootstocks. However, little is known about the microbial communities naturally associated with almond rootstocks in Spain. To address this gap, we sampled roots of six commercial Prunus rootstocks in a 15-year-old almond orchard representing two different genetic backgrounds: P. cerasifera background (PCB) with Rootpac® 20, and Rootpac® R; and P. persica background (PPB), with Cadaman, Garnem, GF677, and Rootpac® 40. Root-associated bacterial, fungal, and arbuscular mycorrhizal fungi communities were evaluated applying a metabarcoding approach.