Strategies in Ericaceae to acquire phosphorus in phosphorus-impoverished habitats in the southwest Australian biodiversity hotspot.

We hypothesised that some Ericaceae exhibit high leaf manganese (Mn) concentrations [Mn], a proxy for rhizosphere carboxylates, and release root carboxylates. We compared their leaf [Mn] with that of positive and negative reference species, known to release carboxylates or not, respectively. To follow up, we measured the carboxylate-exudation rates of targeted species with high and low leaf [Mn] using seedlings grown in low-P nutrient solutions. Using these complementary approaches, we confirmed that Ericaceae in P-impoverished habitats with high leaf [Mn] exhibit a carboxylate-releasing P-mobilising strategy, like non-mycorrhizal Proteaceae. Surprisingly, some species with low leaf [Mn], which occurred in habitats with high soil pH, also released carboxylates. Therefore, low leaf [Mn] cannot conclusively indicate the absence of carboxylate exudation. These species may release carboxylates along with cations such as potassium or magnesium, which increase the rhizosphere pH, thereby decr..., To test our hypothesis that some Ericaceae exhibit high leaf manganese concentrations [Mn], a proxy for rhizosphere carboxylates, and release root carboxylates, we collected fully expanded mature leaves of 32 Ericaceae in southwest Australia from October 2020 to July 2022. We also collected leaves of positive reference species (Proteaceae) and negative reference species (Xanthorrhoeaceae) at most sample locations. When there was no Xanthorrhoea species nearby, we used young expanding leaves of the target species as a negative reference. Total mature leaves [Mn] (Figure 2) and [P] (Figure 3) were oven-dried leaf samples and ground to a fine powder. The acid was digested and analysed by ICP-OES.
Leaf [Mn] was compared using the Welch t-test to assess the difference in mean concentrations between the negative reference and target species. Differences in leaf [Mn] and [P] across species were analysed using one-way ANOVA, and followed by Tukey-Kramer’s HSD post-hoc tests at P < 0.05.
To m..., # Data from: Strategies in Ericaceae to acquire phosphorus in phosphorus-impoverished habitats in the southwest Australian biodiversity hotspot.

Dataset DOI: [10.5061/dryad.9w0vt4btf](10.5061/dryad.9w0vt4btf)

## Description of the data and file structure

For ericoid mycorrhizal Ericaceae, a prominent and diverse family in southwest Australia, it is unclear whether they release carboxylates as a P-acquisition strategy. We hypothesised that some Ericaceae exhibit high leaf manganese (Mn) concentrations [Mn], a proxy for rhizosphere carboxylates, and release root carboxylates.

#### File: Figure_2_(leaf_manganese_concentrations_were_separated_into_each_sanple_area_).xlsx

**Description:**  We collected fully expanded mature leaves of 32 Ericaceae in southwest Australia, to analyse their leaf manganese concentration ([Mn]), they were oven-dried leaf samples and ground to a fine powder, then acid digested analysed by ICP-OES. Leaf [Mn] was compared using the Welch t-test to assess the dif...,