Hydroponic Cultivation Systems to Study Nutrient-Dependent Changes in Inositol Polyphosphate Metabolism in Plants

Recent studies have established a key role of inositol pyrophosphates (PP-InsPs) in regulating phosphate (P_i) homeostasis across various organisms. In plants, PP-InsP levels are intricately linked to P_i status, with this reciprocal regulation being especially pronounced under fluctuating P_i conditions compared to stable nutrient sufficiency or deficiency. Here, we present a hydroponic cultivation protocol for Arabidopsis and rice, designed to simulate distinct and fluctuating P_i regimes. The composition of the nutrient solutions in these systems can be easily adjusted, enabling precise monitoring of changes in PP-InsP metabolism, under both steady-state and dynamic P_i conditions. Plants grown hydroponically under different P_i regimes can also be analyzed for phosphate starvation response (PSR) phenotypes and subjected to inositol phosphate (InsP)/PP-InsP extraction and quantification using methods detailed in other chapters of this special issue.