Microbial community shifts in pearl millet root zone soils with <i>Guiera senegalensis</i> intercropping along a rainfall and soil type gradient in the Sahel

The Sahel of West Africa has vulnerable agroecosystems that threatens food security. A potential solution is intercropping with the indigenous shrub, Guiera senegalensis J.F. Gmel. Previous research Optimized Shrub-intercropping System (OSS) (high density ∼1,500 shrubs ha-1 and coppiced residue incorporation) been shown to dramatically improve pearl millet [Pennisetum glaucum (L.) R. Br.] yield, which attributed improved soil quality, nutrient water availability, harboring a distinct microbial community. Whether this response consistent over climate type gradient in farmers’ fields not investigated. Therefore, objective was determine impact G. senegalenis on chemistry, enzyme activity, microbiomes, metabolic pathways root zone soils fields. experiment three-by-two factorial three rainfall sites along north–south Senegal Peanut Basin two sampling locations (millet within outside influence senegalensis). shifted certain predicted bacterial enriched some fungal genera. Notably, increased crop growth due positively correlated abundance genera having plant promoting properties (e.g., Enterobacter agglomerans Paraburkholderia). Paucibacter, deleterious and/or pathogenic properties, highly abundant non-shrub but completely suppressed beneath shrub. results showed even at typical, low densities, where residues are annually burned, still chemical suggesting more important factor than litter presence shrub roots provide turnover exudates, inputs through hydraulic lift.