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bioRxiv · 10.64898/2026.11.03.764026

Effects of Reduced Watering Regimes on Hops Growth and Rhizospheric Microbial Communities

Abstract

Marked by shifts in historic climatic patterns, the effects of climate change have begun to disrupt biological life worldwide. In agricultural systems, the abiotic effects of climate change such as increased temperatures and reduced rainfall extend beyond crop yield and can be felt at the ecological level through microbial community shifts associated at the interface of the root/soil matrix, known as the rhizosphere. Shifts in rhizospheric community composition have been known to greatly impact crop health, making common garden studies examining the totality of climate related impacts on crops of the utmost importance. Using a combination of both phenotypic and metabarcoding data collected from the rhizosphere, we present a multi-month drought tolerance experiment using the cash crop Humulus lupulus (hops) and five of its cultivars; Cascade, Centennial, Chinook, Comet and CTZ. Statistical analyses of phenotypic data revealed that hops displayed a differential impact on reduced watering strategies while rhizospheric data revealed more consistent patterns of association between microbes and cultivar type. We hope results from our study can be used to further expand our knowledge on the impact of future climate change and necessary reduced watering strategies on agricultural systems, providing insight into potential mechanisms of response for drought tolerance in crop systems.

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McElwee-Adame, A., Mulligan, C., Kibury, K., Glynn, Z., Golshani, M., Alkhafaji, A., Vourlitis, G., Sethuraman, A.. 2026-11-04. Effects of Reduced Watering Regimes on Hops Growth and Rhizospheric Microbial Communities. https://doi.org/10.64898/2026.11.03.764026

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