Moderate Elevation of Ambient Temperature Enhances Phosphorus Deficiency Tolerance in Lotus japonicus under Hydroponic Conditions

ABSTRACT: The combined effects of high temperature stress from global warming and phosphorus (P) deficiency due to limited P rock reserves pose a critical threat to modern agriculture. However, the understanding of the effect of the combined stress on plants are limited. Here, we performed hydroponic culture to investigate the physiological and transcriptional response of the model legume Lotus japonicus to simultaneous moderate high temperature and low P conditions. While both elevated temperature and low P individually reduced shoot biomass, their combination alleviated growth reduction, with greater shoot biomass observed under combined stress than under low P alone. Lotus japonicus enhanced root-secreted acid phosphatase activity in response to low P alone and increased organic acid exudation rate, such as malate and citrate, under elevated temperature, regardless of P supply. We explored root transcriptome, and detected an up-regulated PEPC1 gene, encoding phosphoenolpyruvate carboxylase which suggested to be related with organic acid root exudation. Additionally, elevated temperature also increased metal ion translocation and absorption, anthocyanin levels, and carbohydrate transport in shoots. Transcriptomic analysis revealed that low P stress altered heat shock protein (HSP) expression, likely due to reduced ATP availability. This study demonstrates that L. japonicus employs distinct and overlapping strategies to adapt to the combined stresses of elevated temperature and P deficiency, including adjustments in exudation patterns, nutrient transport, and stress-responsive gene expression.

ORGANISM(S): Lotus japonicus

PROVIDER: GSE300599 | GEO | 2025/12/31

REPOSITORIES: GEO